^1 CORNE LL UNIV ERSITY THE Mamn UplFrtttarg Htbrar^ FOUNDED BY ROSWELL p. FLOWER for the use of the N. Y. State Veterinary College 1897 5577 This Volume is the Gift of Alice ^« I'listan from, the libraiy.of. Dr. Henry W. Dustan ' 98 Digitized by Microsoft® SF 915.H|f"*"""'™'-*«V Library *ZiII'niM,i?.',,;(;?i!l!.';!™''y therapeutics and 3 1924 000 873 087 Digitized by Microsoft® This book was digitized by Microsoft Corporation in cooperation with Corneii University Libraries, 2007. You may use and print this copy in iimited quantity for your personai purposes, but may not distribute or provide access to it (or modified or partiai versions of it) for revenue-generating or other commerciai purposes. Digitized by Microsoft® Digitized by Microsoft® Digitized by Microsoft® A MANUAL VETERINARY THERAPEUTICS AND PHARMACOLOGY BY E. WALLIS HOARE, F.R.C VS. NEW YORK : WILLIAM R. JENKINS, VETERINARY PUBLISHER AND BOOKSELLER. 851 & 853 Sixth Avenue. 1900. Digitized by Microsoft® Digitized by Microsoft® PREFACE. The following work is iatended as an introduction to the important and extensive subject of veterinary thera- peutics and pharmacology. It is divided into three parts. Part I. is introductory, and deals in a concise manner with the subjects of diagnosis and the general symptoms of disease in relation to therapeutics ; the actions and uses of medicinal agents are also briefly noticed in a general manner. Part II. is devoted to general therapeutics, and in it the author has followed the plan adopted by Dr. Mitchell Bruce in his excellent work on ' Materia Medica and Therapeutics,' viz., that of discussing the actions and uses of remedies under the physiological systems of the body. Part III. deals with special therapeutics, and here again the author has arranged the actions of drugs on the plan adopted by Dr. Mitchell Bruce, which consists in discussing their actions from their first contact with the body, to their effects on the various organs and tissues until they become eliminated. By this method the student is enabled to thoroughly Digitized by Microsoft® iv PREFACE understand the specific actions of medicinal agents and their rational employment in the treatment of disease. The author has endeavoured as far as possible to group together those drugs possessing a similarity in action, and he ventures to hope that this method will be found preferable to following them according to their natural orders or alphabetically. Toxicology has only been briefly touched on whenever necessary, and for further informa- tion on this subject the student is referred to more pre- tentious text-books. Only an outline of the preparation of drugs has been given, and botanical characters, impurities, etc., are pur- posely omitted, as the author does not consider these matters of importance to the veterinary student of the present day, whose time has already sufficient demands upon it in mastering the action of drugs and their em- ployment in the treatment of disease. The wholesale chemists have relieved both practitioners and students of a vast amount of trouble by preparing drugs in a reliable manner, and our time and energies are now more usefully employed in endeavouring to keep pace with the ever-increasing discoveries in the science of therapeutics. A special chapter has been devoted to ' Anaesthetics ' in consequence of the importance of this subject in the present day, and in it the author has given the results of practical observation with reference to the employment of chloroform in veterinary surgery. In the Appendix some practical information is given on the subject of prescribing and dispensing, together with examples of prescriptions, wliich it is hoped will prove of some assistance to the student. The author gratefully acknowledges the valuable assist- ance which he has received in the preparation of this Digitized by Microsoft® PREFACE V work from Professor J. Maequeen, Eoyal Veterinary College, London ; also from Professor P. Smith, A.V.D., Army Veterinary School, Aldershot. He has also to ex- press his indebtedness to Professor W. Williams, Prin- cipal of the New Veterinary College, Edinburgh, for sound and rational teaching on all details of therapeutics re- ceived both as a student from his able lectures and from his eminent works on veterinary medicine and surgery. The author is fully aware of the many omissions and imperfections which must of necessity exist in a work of this kind, in consequence of the limited time at his dis- posal for reference and research, and he hopes that the attempt may stimulate some abler hand to complete the task. If it should prove of assistance to the veterinary student in commencing the consideration of an important and often difficult subject, and thus indirectly serve the pro- fession even to a slight degree, the author will feel that his efforts have been amply rewarded. 18, Cook Stkeet, Ooek, December, 1894. Digitized by Microsoft® LIST OF WORKS CONSULTED. Veterinary Medicines, Mr. Pinlay Dun, 1882. Materia Medioa and Therapeutics, Dr. Mitchell Bruce. Handbook of Therapeutics, Dr. Einger. Materia Medica and Therapeutics, Dr. Phillips. Companion to the British PharmacopcBia, Mr. P. Squire, 1894. Materia Medica, Therapeutics and Toxicology, Dr. H. C. Wood. The Specific Action of Drugs, Messrs. Burness and Mavor. Precis de Th^rapeutique, de Mati^re Medicale, et de Pharmacie V^tdrinaires, M. P. Cagny. Veterinary Pharmacology and Therapeutics, Mr. J. B. Gresswell. Veterinary Posology^ Mr. G. A. Banham. The Principles and Practicd of Veterinary Medicine, Professor Williams. The Principles and Practice of Veterinary Surgery, Professor Williams. Equine Medicine, Professor Eobertson. Veterinary Physiology, Professor Smith. Manual of Equine Medicine, Mr. J. B. Gresswell. The Principles and Practice of Medicine, Dr. A. Flint. The Journal of Gomparative Pathology and Therapeutics. The Veterinarian. The Veterinary Journal. The Veterinary Becord. The American Veterinary Bevieiv. Digitized by Microsoft® CONTENTS. Preface List op Works consulted PAGE - iii - vi PAET I. CHAPTER I. INTEODUOTOEY. Importance of Clinical Observation — Pharmacology — Materia Medioa — General Therapeutics — Toxicology 1 — 5 CHAPTEE II. DIAGNOSIS AND THE GENERAL SYMPTOMS OP DISEASE. The Art of Diagnosis — Importance of a Correct Diagnosis — Treatment of Symptoms — The Pulse — Varieties of Pulse — Strength and Weakness of Pulse— Symptoms connected with the Condition of the Visible Mucous Membranes — The Temperature — Fever — Symptoms connected with the Respiratory Functions — Varieties of Respiration — Cough — Symptoms furnished by the Condition of the Surface of the Body and Extremities — Symptoms furnished by the Secretions and Excre- tions ..---- 6—24 CHAPTER III. THE ACTIONS AND USES OF DHU0S. Physiological Action — Manner in which Drugs act in the Treatment of Disease — Plan for Description of the Digitized by Microsoft® CONTENTS Actions of a Drug — Immediate Local Action — Action in or on the Blood— Specific Action — Remote Local Action ------ 25—31 CHAPTER IV. ON PKESCEIBING. Selection of the Remedy — Contra-indications — Idiosyn- crasy — Circumstances which modify the Action of Medicines — The Modes and Forms of Administration of Drugs — The Species of Animal — Age and Size — The Effect of Diseases — The Dose — Frequency — Time — Duration, Toleration, Habit, Accumulation — The Effect of Climate and Surroundings — Combinations — Chemical and Physiological Incompatibles — The Pre- scription ------ 31 — 47 PAKT II. OENEBAL THEBAPEUTIGS. CHAPTER L INTEODnOTOEY. Four Considerations of General Therapeutics — Health — Pharmaco-dynamics — Physiological Action — Pathology — Recoverv^-Natural Means of Recovery — Different Kinds of Treatment — Rational and Empirical Treat- ment --.-.. 48—56 CHAPTER n. DIGESTION — THE MOUTH. Physiological Relations —Pharmaco-dynamics — Sialagognes — Anti-sialagogues — Demulcents — Pathological Rela- tions — Loss of Taste — Disorders of the Secretions of the Mouth— Salivation — Derangements of the Excre- tions of the Mouth — Glossitis— Natural Recovery Therapeutics - . - - . 57 — g2 Digitized by Microsoft® CONTENTS ix CHAPTER III. DIGESTION — THE STOMACH. PAQK Physiological Relations — Pharmaco-dynamics — Digestive Adjuvants — Alkaline Stomachics — Gastric Stimulants —Gastric Sedatives — Gastric Disinfectants — Gastric Astringents — Gastric or Stomachic Tonics — Specific Nervo- muscular Stimulants — Antacids — Carminatives — Pathological Relations — Dyspepsia — Acute Indiges- tion — Chronic Indigestion — Gastritis, Acute and Chronic ■ — Pienalvia — Hoven — • Pyrosis — Gastric Catarrh — Natural Recovery — Therapeutics — Treat- ment of Acute Indigestion — Treatment of Chronic Indigestion — Treatment of Gastritis - - 62 — 77 CHAPTER IV. ON VOMITION. Physiological Relations — Pharmaco-dynamics — Emetics — Anti-emetics — Pathological Relations — Natural Re- covery — Therapeutics — The Use of Emetics - 77 — 81 CHAPTER V. DIGESTION — THE INTESTINES. Physiological Relations — Pharmaco-dynamics — Drastics — Astringents — Constringents — Saline Purgatives — Cathartics and Hydragogue Cathartics — Nervo-mus- oular Intestinal Stimulants — Nervo-muscular Intestinal Sedatives — Cholagogues — Anthelmintics — Vermifuges — Vermicides — Pathological Relations — Diarrhoea — Constipation — Impaction of the Large Intestines — Colic— Enteritis — Volvulus and Intussusception — Flatulent Colic— Natural Recovery — Therapeutics — Uses of Purgatives — Contra-indications — Treatment : of Diarrhoea ; of Flatulent Colic ; of Enteritis ; of Intestinal Obstruction - - - - 81 — 99 CHAPTER VI. ON ENBMATA. Uses of Enemata — Ures of Smith's Rectum-tube — Mode of Using— Nutritive Enemata - - - 100—103 Digitized by Microsoft® X CONTENTS CHAPTER VII. THE LIVBE. PACE Physiological Belations — Pharmaco-dynamics — Chola- gogues — Pathological Relations — Jaundice — Affections of the Liver — Natural Recovery — Therapeutics - 103 — 109 CHAPTER VIII. THE BLOOD. Physiological Relations — Pharmaco-dynamics — Patholo- gical Relations — Plethora — Ansemia — Affections of the Blood — Natural Recovery — Therapeutics - 110 — 117 CHAPTER IX. METABOLISM, OE THE PEOCESS OP NTJTEITION. Physiological Relations — Pharmaco-dynamics — Action of Alteratives — Pathological Relations — Natural Re- covery — Therapeutics - - . . 117 — 125 CHAPTER X. THE CIECULATOEY SYSTEM. Physiological Relations — Pharmaco-dynamics — Direct Cardiac Stimulants — Direct Cardiac Depressants — Pathological Relations — Functional Disorders of the Heart — Organic Diseases of the Heart — Haemorrhage and its Consequences — Natural Recovery — Thera- peutics — Treatment of Functional and Organic Diseases of the Heart — Treatment of Hsemorrhage — Syncope — Venesection : Uses and Contra indications - 125 — 1^2 CHAPTER XI. THE EESPIEATOEY SYSTEM. Physiological Relations — Pharmaco - dynamics — Expec- torants — Disinfectant Expectorants — ■ Pathological Relations — Dyspnoea — Cough — Natural Recovery — Therapeutics - - . . . 142 — 153 Digitized by Microsoft® CONTENTS CHAPTER XII. THE NEEVOUS SYSTEM. PAGE Physiological Relations — Pharmaco -dynamics — Local Stimulants — Local Anaesthetics — Motor Stimulants — Motor Depressants — General Anaesthetics — Narcotics — Hypnotics — Pathological Relations — Pain — Paralysis — Unconsciousness — Delirium — Natural Recovery — Therapeutics — The Use of Anodynes - - 153 — 171 CHAPTER Xlir. THE KIDNEYS. Physiological Relations — Pharmac6-dy namics — Diuretics — Different Classes of Diuretics — Renal Depressants — Pathological Relations — Different Forms of Bright's Disease — Oxaluria — Azoturia — Hsemo-albuminuria — Natural Recovery — Therapeutics — TheUseof Liuretics — Treatment of Various Renal Affections - 171 — 183 CHAPTER XIV. THE BODY HEAT AND ITS REGULATION ; THE SKIN. Physiological Relations — Pharmaco-dynamics — Diapho- retics — Different Forms of Diaphoretics — Anhydrotics — Antipyretics — Pathological Relations — Causes of Pyrexia — Changes produced by Pyrexia — Varieties of Fever — Disorders of Perspiration — Natural Recovery — Therapeutics — Uses of Diaphoretics and Antipyretics 183—194 CHAPTER XV. THE THEKAPEDTICS OF THE SURFACE OF THE BODY. Pharmaco - dynamics — Counter - irritants -:- Theory of Counter-irritation in Therapeutics— Uses of Counter- irritants — Baths and Allied Measures — Cold and Hot Applications — Fomentations — Poultices — Surgical Applications — Deodorants — Antiseptics — Disinfectants — Astringents — Stimulants — Styptics — Caustics and Escharotics — Vesicants — Anodynes — Actions of Medi- cinal Agents on the Eye — Local Ansesthetics— My- driatics— Myotics . - . - 195—207 Digitized by Microsoft® xii CONTENTS PART III. SPECIAL TREBAPEUTIGS. CHAPTEK I. INTKODUCTOKY. PAGE Classification of Drugs — Preparations — Alkaloids — Neutral Organic Principles . . . . '208 — 213 CHAPTER II. THE INOEGANIC MATERIA MBDIOA. General Remarks on Alkalies — Potassium and its Medicinal Salts — Sodium and its Medicinal Salts — Ammonium and its Medicinal Compounds — Calcium and its Medicinal Salts — Magnesium and its Medicinal Salts ..---. 214—240 CHAPTER III. iNOBGANic MATEEIA MBDIOA — Continued. The Metals — Lead and its Medicinal Salts — Antidotes to Lead Salts — Argentum Nitrate — Zinc and its Medicinal Salts — Copper and its Medicinal Salts — Antidotes to Copper Salts — Aluminium, Alum — Iron and its Medi- cinal Salts— Mercury and its Preparations — Antidotes, Mercury and Zinc Cyanide — Phosphorus — Hypophos- phites of Calcium and Sodium — Arsenic and its Preparations — Antidotes to — Antimony and its Pre- parations — Antidotes to — Bismuth Subnitrate - 241 — 291 CHAPTER IV. INORGANIC MATERIA MEDiCA — Continued. The Non-metallic Elements : Chlorine — Iodine and its Preparations — Bromine and its Preparations — Sulphur and its Preparations — Carbon and its Preparations 292—307 Digitized by Microsoft® CONTENTS CHAPTER V. INORGANIC MATERIA MEDICA — Continued. PAGE Acids : Inorganic Acids — Sulphuric Acid — Nitric Acid — Hydrochloric Acid — Nitro-muriatic Acid — Boric Acid — Borax — Chromic Acid — Organic Acids — Acetic Acid —Citric Acid— Tartaric Acid— Water - - 308—324 CHAPTER VI. THE CARBON COMPOUNDS. Alcohol — Forms of Alcohol — Actions of Alcohol — Medi- cinal Uses — Indications and Contra-indications of Alcohol ------ 325—335 CHAPTER VII. THE CARBON COMPOUNDS — Continued. General Remarks on the Action of Ansesthetics — Nitrous Oxide — Chloroform — Actions of Chloroform — Stages of Chloroform Anaesthesia — Toxic Effects of Chloro- form — Analysis of Chloroform Anaesthesia — Specific Uses of Chloroform — Method of Administration and Precautions to be observed during Anaesthesia — Dif- ferent Forms of Apparatus — Period of Time — Amount of Drug required and Recognition of the Condition o£ Anaesthesia — Administration of Chloroform to the Dog — Other Uses of Chloroform — Ether — Actions of Ether, and Comparison with Chloroform — Specific Uses— Liquor Sodii Ethylatis - - - 336—357 CHAPTER VIII. THE CARBON COMPOUNDS — Continued. Hydrate of Chloral — Cro ton-chloral Hydrate — Chloralamid — Paraldehyde — Sulphonal — Amyl Nitrite — Sodium Nitrite — Nitroglycerine — Spirit of Nitrous Ether — Hydrocyanic Acid — Aqua Laurocerasi — Carbolic Acid — Resorcin — Naphthalin — Creolin — Pyoktanin — Anti- pyrin — Antifebrin — Phenacetin — Cbinoline — Kairin — ThaUin — Salol — Ichthyol — Creasote — lodof i Tm — lodol— Aristol- Vasehne - - - 358—384 Digitized by Microsoft® PAGE xiv CONTENTS CHAPTER IX. THE VEGETABLE KINGDOM. Aconite — Veratrine— Stavesacre — Colchioum - 385 — 393 CHAPTER X. THE VEGETABLE KINGDOM — Continued. Opium — Morphine — Apomorphine — Cannabis Indica — Cocaine ------ 394-413 CHAPTER XI. THE VEGETABLE KINGDOM — Continued. Belladonna — Atropine — Hyoscyamus — Stramonium — Duboisine — Tobacco — Lobelia — Conium — Curare — Calabar Bean — Physostigmine — Jaborandi — Pilocar- pine — Nitrate of Muscarine — Gelsemium — Ergot — Nux Vomica — Strychnine — Caffeine - - 414 — 443 CHAPTER XII. THE VEGETABLE KINGDOM — Continued. Digitalis — Convallaria — Stropbanthus — Squill - 444- — 451 CHAPTER XIII. THE VEGETABLE KINGDOM — Continued. General Actions of Simple and Aromatic Bitters : Calumba — Quassia — Gentian — Aurantium — Hydrastis. General Actions of Aromatic Volatile Oils : Oil of Cloves — Oil of Peppermint — Menthol — Thymol — Oil of Origanum — Oil of Lavender — Oil of Rosemary — Ginger — Anise — Oil of Anise — Arnica — Oil of Turpentine — Tere- bene— Resin— Oil of Tar— Pitch— Oil of Cade— Oil of Juniper — Oil of Eucalyptus — Camphor — Benzoin — Benzoic Acid — Balsams of Peru and Tolu — Myrrh — Valerian — Asaf oetida — Galbanum — Ammoniacum — Capsicum — Mustard — Actions and Uses of Mustard as a Counter-irritant - - - . 452 — 473 Digitized by Microsoft® CONTENTS XV CHAPTER XIV. THE VEGETABLE laNGDOM — Continued. PAGE Purgatives — Croton Oil — Elaterium — Oolooynth — Gam- boge — Jalap — Scammonj; — Podophyllin — Aloes — Hints on the Administration of Aloes — Superpurga- tion and its Treatment — Aloes in the Treatment of Spasmodic Colic — Contraindications of Aloes — Senna — Bhubarb — Castor Oil — Raw Linseed Oil — Cascara Sagrada — Syrup of Buckthorn — Taraxacum — Euony- min - 479—495 CHAPTER XV. THE VEGETABLE KINGDOM — Continued. Anthelmintics: Filix Mas — Santonin — Areca-nut — Kousso — Kamala — Spigelia — Pomegranate Root Bark - 496, 497 CHAPTER XVI. THE VEGETABLE KINGDOM — Continued. Tannic Acid — Gallic Acid — Pyrogallic Acid — Catechu — Kino — Logwood — Hamamelis — Ipecacuanha — Buchu -Pareira 498-504 CHAPTER XVII. THE VEGETABLE KINGDOM — Continued. , Cinchona— Quinine— Salicylic Acid— Salicylate of Soda— Salicin— Thioform . . - - 505—515 CHAPTER XVIII. THE VEGETABLE KINGDOM — Continued. Olive Oil— Hard Soap— Soft Soap— Glycerine— Treacle— Tragacanth — Gum Acacia — Liquorice — Linpeed — Barley Water-Wheat Flonr— Starch— Marsh Mallow — Chaulmugra Oil - - - - 515—520 Digitized by Microsoft® xvi CONTENTS CHAPTER XIX. THE ANIMAL KINGDOM. PAGE Lanoline — ^Lard — Spermaceti — Gelatine — Ood-liver Oil — Honey— Oantharides — Precautions to be observed in Blistering - . . . . 521—527 APPENDIX. VETEBINABY PHABMACY. Importance of Accuracy and Neatness in Dispensing — Weights and Measures — Symbols — Relation of Mea- sures to Weights — Domestic Measures — Metric System — Prescribing and Prescription-writing — Importance of writing Prescriptions in a Clear Manner — Different Parts of a Prescription — Abbreviations used in Pre- scriptions — The Approximation of Doses in Mixtures — Table for approximating Doses in the Different Sizes of Phials — Table for computing Different Strengths of Solutions — Hints on the Administration of Medicines to the Different Species of Patients — Precautions in administering Fluid Forma of Medicines — Powders — Electuaries — Hypodermic and Intratracheal Injections — Administration of Medicines by Toope's Trocar and Cannula — Medicine Chest — Examples of Prescriptions 628—552 Index ...... 553—560 COKRIGENDA. Page 36, line 8, for ' Intei tracheal ' read ' Intratracheal.' Page 226, line 14, for ' p. 293 ' read ' p. 296.' Page 226, line 15, after ' Sodii Salicylas ' add ' (see p. 510).' Page 226, line 16, after ' Sodii Hypophosphis ' add ' (see p. 275).' Page 236, line 2 from boitom, for ' p. 276 ' read ' p. 275.' Page 261, after line 16 add '(see p. 370).' Page 291, last line, after ' dithiosalicylic acid' add ' (See p. 513).' Page 374, line 10, for ' intertracheal ' read 'intratracheal.' Digitized by Microsoft® YETERINARY THEEAPEUTICS AND PHARMACOLOaT PART I. CHAPTBE I. INTRODUCTORY. Veteeinaey therapeutics is the subject which relates to the treatment of disease in the domesticated animals. Taken in its wide sense, it would include all the means at our disposal in our efforts to combat disease and effect as early a restoration to health as possible. Thus, the subject would embrace, in addition to the various drugs which we employ, the details of hygiene and all that con- cerns the care of animals affected by disease, which are most important and vital adjuncts in treatment, and without a knowledge of which we cannot expect medi- cinal agents to be of service. The student must, first of all, be familiar with animals in a state of health before he can recognise the changes produced by disease, and appreciate those symptoms which will lead him to a correct diagnosis and to rational treatment. He must become familiar with the actions of the various drugs on the different organs of the body in a state of health before he can apply them in the treatment of disease. 1 Digitized by Microsoft® 2 VETERINARY THERAPEOTICS It will not be sufficient for him to prescribe remedies in one case because similar remedies happened to afford relief in another case of the same nature ; he must reason out the rationale of how each medicinal agent acts, and treat every case on its merits, according to the indica- tions which are placed before him. The student must also recognise what is termed the vis medicatrix naturce, or the power of nature to cure disease, and by appreciating this power he will learn that the groundwork of rational treatment consists in helping the efforts of nature as much as possible, and using no means or remedies which are likely to frustrate them. He will also, as he studies the effects of the different medicinal agents clinically, be often struck by the fact that in many cases where a certain curative effect is ascribed to the use of a particular drug, it was in reality nature that caused the so-called cure. It will also be apparent to him that there are very few diseases which we can directly act on by means of medi- cinal agents, and bring about what is termed a cure; in the majority of instances we treat the secondary effects rather than the primary disease. Take, for instance, a case of pneumonia. Here we cannot act directly on the lung, so as to shorten the course of the disease — we know that it must run a definite course — and our efforts are directed to keep up the strength of the patient, and to combat any complications which may arise as best we can. We pay special attention to the character of the pulse, to the temperature, and to the respiratory movements and also to the digestive system, and by every means possible endeavour to promote the appetite and tempt the patient to partake of nourishing and easily digested Digitized by Microsoft® INTRODUCTORY 3 food. The veterinary therapeutist is placed at great dis- advantages as compared with his confrere in human medicine. The latter has only the individuals of his own species to deal with ; he can form his diagnosis both on information derived from the patient himself, termed subjective symptoms, and also on the symptoms which he observes by an examination of the patient, termed objective symptoms. The veterinary therapeutist, on the other hand, has patients to deal with which, being incapable of the powers of speech, cannot afford him anything in the way of subjective symptoms. All his efforts must be directed to the observation of objective symptoms, to appreciate which correctly re- quires a long period of study, and careful training com- bined with zealous clinical study. He has to treat different species of animals, each requiring careful study, in order to make his general therapeutical knowledge applicable to the peculiarities which exist in the different animals. Thus, to treat the diseases, of cattle in a rational manner requires a similar clinical training to that required in the diseases of horses, and the same may be said with reference to the diseases of dogs. He has also often to depend on the history of a case from attendants either very ignorant or unreliable, and, as a rule, anxious to shield themselves from blame or responsibility; and, as often occurs, the remedies he prescribes and the instructions given are not carried out in a satisfactory manner. In veterinary practice we also find that cases are not often brought for treatment until the disease is well established, either by reason of its existence not having been noticed in the early stages, or because the owners or attendants have been trying remedies themselves, such Digitized by Microsoft® 4 VETERINARY THERAPEUTICS remedies being often irrational and injurious to the patients. It must be clearly impressed on the student that no amount of knowledge derived from text-books or lectures will enable him to treat diseases in their various phases in a satisfactory manner ; he must combine careful clinical study with theory, and never fail to watch the course of a case attentively, and to note the signs of improvement and the effects of the medicinal agents employed. He must also cultivate his powers of observation in order to be able to notice any changes which may occur in the condition of . a patient during the course of an affection, and also to correctly note the presence of diagnostic symptoms during his examination of a patient. We have now to consider the meaning of the term Pharmacology. In former times this term referred to the preparation and source of the various drugs, as well as to a considera- tion of their chemical and physiological actions. It is now generally recognised as referring to the action of the various drugs on the different organs of the body in a state of health. The subject of Materia Medica will teach the student the sources of each drug, its technical name, its formula, its properties, the preparations made use of by the therapeutist, its impurities, the substances with which it is compatible or incompatible, and its doses for the various animals. In this work it is not intended to notice the subject of materia medica further than to give the technical name of each drug, its source, the prepara- tions of the drug which are in use in ordinary practice, and the doses for the different animals. Digitized by Microsoft® INTRODUCTORY 5 We shall also notice those drugs concerning which we are in possession of certain definite facts with reference to their physiological action, and, as a result of this know- ledge, of their application in the treatment of disease. We shall find that there are medicinal agents in use which we cannot explain in a satisfactory manner as to their therapeutical action ; we know by experience that they produce certain results, but the manner in which they produce these results is not at all clear. The number of such agents, we shall find, is gradually de- creasing as our knowledge of pathology is increasing. In addition to our consideration of the actions and medicinal uses of the various drugs employed in the treatment of disease, we have to notice some of the major details of hygiene, and the important points in connection with the care of sick animals. As a result of our knowledge, gained from a considera- tion of the special actions and uses of each drug, we are enabled to collect certain facts and principles, and these are classed under the heading of General Therapeutics. We can also class a certain number of drugs which re- semble each other in their actions under separate head- ings, but we shall find, in many instances, that drugs have actions which entitle them to be placed under more than one heading, and such actions will vary according to the doses given. Toxicology, which treats of the effects of the various poisons in the system, with the post- mortem appearances and the antidotes, will receive a brief notice in Part III., in the separate description of each agent. In the next chapter we shall consider the subject of Diagnosis and the General Symptoms of Disease. Digitized by Microsoft® VETERINARY THERAPEUTICS CHAPTEE IT. DIAGNOSIS AND THE GENERAL SYMPTOMS OF DISEASE. The firsb essential in the rational treatment of disease is a correct diagnosis, and if, from the obscurity or non- development of the symptoms, at our first examination of the patient, this is impossible, we have then to direct our efforts to the treatment of whatever symptoms pre- sent themselves. The art of diagnosis consists in ar- ranging the symptoms presented into signs of disease ; or, in other words, we come at the true origin of the symp- toms, which we term the cause. We have to consider that there are some symptoms which are so characteristic to the practised eye that by recognition of them we can distinguish one disease from the other. Such are termed diagnostic symptoms. If a set of symptoms are peculiar to a certain disease, they are termed pathognomonic. We have also to notice what are termed the general symptoms of disease, which are those changes occurring in many and varied diseases, and which, in conjunction with diagnostic symptoms, lead us to a correct diagnosis, and also enable us to judge of the condition of the patient and the indications for treatment. They are the first phenomena looked for in the ex- amination of a patient, and in the absence of diagnostic symptoms they give us valuable information with re- ference to primary indications for treatment, and are also of vital importance during the course of long and severe affections. Thus we have symptoms connected with (1) the con- dition of the pulse ; (2) the visible mucous viembranes ; Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 7 (3) the temperature; (4) the respiratory functions ;. (5) the surface of the body ; (6) the secretions and excretions. All these will merit a short consideration ; but before proceeding to this we shall have to briefly notice the value of a correct diagnosis in the treatment of disease as compared with the indications afforded by the symp- toms. We must be cognizant of the fact that there are many affections presenting symptoms to our notice, which symptoms do not indicate to us the true nature of the disease ; or, in other words, if we were to endeavour to treat the affection by acting on the symptoms, we should not be successful. We meet with cases where the symptoms presented would lead us to infer that a certain organ, or set of organs, are affected by disease, whereas in reality, by means of reflex action and other causes, the symptoms arise from a different system of organs altogether. Take, for example, a case of a dog affected with in- testinal parasites, or foreign bodies in the stomach, and we often find symptoms which, without careful con- sideration, we would ascribe to a brain affection. Ob- viously, to treat the brain symptoms would be of little value, as the cause would be still at work ; we must in all eases endeavour to ascertain the cause when possible, and our efforts will then be directed to remove it. Or, again, take a case of functional disorder of the heart, arising from indigestion or from parasites in the ali- mentary canal. Here it would be useless to try and treat the disorder of the heart ; we must endeavour to ascertain the cause, and act on this as much as possible. Or take that affection in horses known as diabetes in- sipidus, where the animal is affected with constant thirst, and is continually passing urine. Here, along with the Digitized by Microsoft® 8 VETERINARY THERAPEUTICS use of medicinal agents, we have to inquire after the quality of the food, and change it, as the affection is in reality due to deleterious changes in the food. Many other instances might be cited of the same nature, such as a cough, depending on indigestion or various other causes, which must be treated according to its source ; then we have cases of derangement of the di- gestive system, due to dental irregularities, etc. But sufficient examples have been shown to demonstrate to the student how careful he should be in ascribing any symptom, or set of symptoms, to their real cause, and along with a physical examination of the patient to form a correct diagnosis. But we have to consider that there are many instances brought under the notice of the practitioner in which it is not possible at the time to form a correct diagnosis, either from the obscurity of the symptoms or from non- development of diagnostic symptoms. Thus, take a case of that common affection termed influenza. In one case we have presented to us the occurrence of rigors, with staring coat and coldness of the extremities ; in another case we have weakness of the hind extremi- ties and general muscular debility, etc. We find the temperature is 104° or 105°, pulse and respiration accelerated, accompanied by almost total loss of appetite. But these are symptoms common to many affections ; we cannot predict what organs will become affected in a day or so ; either pneumonia, bronchitis, or pleurisy may supervene, the presence of which we shall be able to ascertain by a physical examination of the chest. What, then, are the indications for the therapeutist? Obviously it would not be wise to defer treatment until he can be sure of a correct diagnosis. Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 9 He is quite well aware that such affections must run a definite course, and that, whatever organs may eventually hecome attacked, he must have two ends in view : 1st. To overcome the rigors, when such exist, by the administration of diffusible stimulants, so as to divert the circulation to the cutaneous vessels, and thus avoid a tendency to internal congestions. 2nd. To reduce the abnormal temperature by the administration of febrifuges, and to attend carefully to hygienic and dietetic measures. Again, take cases where the prominent symptom is the manifestation of pain. We see this symptom in a great variety of affections ; thus, it occurs in simple colic, in enteritis, in peritonitis, in volvulus, in affections of the stomach, and also in pleurisy, nephritis, etc. The experienced practitioner judges by the character of the pain of its probable cause, but in many instances in the primary stages this is not possible ; and in others such a variety of symptoms present themselves that it is only in the postmortem examination he sees how much in error he may have been in his diagnosis. All his efforts must be directed in such cases to the alleviation of the pain, as continued pain exerts such a depressing influence on the whole system as to quickly lead to a fatal result. In cases of acute enteritis, volvu- lus, etc., which are usually fatal, all that the therapeu- tist can do is to administer anodynes, with a view to alleviate the agonizing pain, as curative results are seldom possible. Even if he were to form a correct idea of the nature of the affection on which the pain depended in such cases, his treatment would not be altered, and in reality it is the symptom which he endeavours to combat, and not the cause. Digitized by Microsoft® 10 VETERINARY THERAPEUTICS But in cases of simple colic and affections of the stomach, such as acute indigestion, etc., also in cases where pain exists in systems other than the digestive, such as pleurisy, nephritis, etc., he is enabled more readily, by studying other symptoms presented, to form a diagnosis, and to bring to his assistance valuable aids in the way of therapeutic agents. Thus, in the case of simple colic, depending on a spasmodic contraction of the muscular coats of the intestines, due to the presence of irritating ingesta, it is clear that, in addition to relieving the pain, we should also direct our efforts to the removal of the cause by the, administration of mild purgatives, such as ol. lini, and also by the administration of enemas. Such remedies will remove the source of irritation and thus prevent a recurrence of the pain. In the other instances stated, appropriate treatment must be adopted in addition to the alleviation of the existing pain. Thus, in the case of affections of the urinary system accompanied by pain, we have to bring to our aid a chemical and microscopical examination of the urine, in addition to a careful observation of the symptoms presented, before we can form a correct diagnosis and prescribe suitable treatment. In the majority of cases of affections of the respiratory system, the practitioner has to depend more on treating the general symptoms which present themselves, instead of endeavouring to act directly on the organs affected. The pulse and temperature will require careful watching, and the strength must be kept up by stimulants if neces- sary, and by tempting the animal to partake of nourishing and easily digested food. The irrational treatment of former days, viz., by ad- ministering sedatives and by blood-letting, etc., combined Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 11 with severe counter-irritation, and pouring quantities of fluid foods down the animal's throat, can only be ascribed to a prevalent idea that the course of the disease could be cut short by the adoption of such measures. In considering the subject of the general symptoms of disease, the student will find much scope for reflection. As previously remarked, such symptoms cannot by them- selves lead him to a correct diagnosis, but they afford him valuable indications as to the condition of the patient, and as a guide to the adoption of therapeutic measures during the course of febrile affections. We shall first consider the indications afforded by a study of the character of The Pulse. As we are aware that the pulse is an index of the con- dition of the heart, and that so long as the action of the heart is maintained we have life in the animal, we see at once the great importance of the character of the pulse to the therapeutist. It is essential that the student should make himself familiar with the character of the healthy pulse in the different animals, so as to be able to appreciate the changes induced by disease. He should carefully note its tension, its regularity, its volume, before he proceeds to study the alterations presently to be described. The pulse is usually regarded as the wave which is sent through the arterial system with each contraction of the heart. Its. character depends on the condition of the heart itself, and also on the condition of the walls of the blood- vessels, and the quality and quantity of the blood itself. Depending on so many circumstances, we cannot be surprised at observing how easily its character may be Digitized by Microsoft® 12 VETERINARY THERAPEUTICS modified, and when we regard the wonderful mechanism by which the heart is controlled, we must be aware that, in order to draw correct conclusions, a very close and careful examination will be required. If the heart is affected by organic disease, then it is palpable that the pulse will be altered in character according to the parts of the organ affected. If the walls of the arterial vessels are relaxed, the blood will pass more easily into the veins, and, as a result, the arterial tension will be shght, and the pulse will feel soft and compressible, and also large. The pulse- wave may become exaggerated, and may be mistaken for an extra pulse-beat, such a condition being termed dicrotism. If the quantity or quality of the blood itself be altered, there will also be a change in the character of the pulse. Thus plethoric animals generally, but not always, have a strong, full pulse. Then, in certain diseases, such as purimra hcemorrhagica in horses and red water in cattle, the quality of the blood is deteriorated, and the pulse may be found fluttering or trembling, appearing to have a double beat, with the artery relaxed. So that the student will clearly see the great possibility of a grave error in diagnosis, if he were to depend on the character of the pulse alone, without taking other symptoms into consideration. There is a common tendency to ascribe many cases where irregularity or intermittency in the pulse-beats occurs to be due to cardiac affection, whereas we often find the disorder to be functional, and depending on de- rangements of the digestive organs or nervous affections. The normal standard of the pulse of the horse is generally stated to be 40 beats per minute, but this is subject to variation as regards nervous temperament, excitement, etc. Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 13 In cattle the pulse cannot be regarded as a reliable guide, as even the act of approaching the animals will be sufficient to cause increased pulsations, as also does the act of rumination. The pulse of the dog varies, according to the size and breed of the animal, from 80 to 100 per minute, and, in judging of its character, it is essential that the animal be not excited in any way, and be quietly approached and handled. The varieties of the pulse which are found in veterinary practice require for their appreciation careful clinical study. The following varieties are recognised : 1. The frequent pulse, or its reverse, the infrequent pulse. 2. The quick pulse, or its reverse, the slow pulse. 3. The large and the small pulse. 4. The compressible and the incompressible, also termed the hard and the soft pulse. 1. The FrecLuent Pulse is referable to the number of beats in a given time. As previously remarked, this number may vary within certain limits in individuals of different temperaments. Exercise or excitement will cause a frequent pulse, which will return to normal when the animal becomes passive. Again, excessive repletion of the digestive organs will increase the frequency of the pulse, and we find in the various fevers and in inflammations of visceral organs that the frequent pulse is usual in the primary stage. Moderate blood-letting will increase the frequency of the pulse-beats ; excessive blood-letting causes extreme frequency, which is also found in diseases characterized by great prostration and debility. The Infrequent Pulse is often associated with slowness Digitized by Microsoft® 14 VETERINARY THERAPEUTICS it is found in cases of brain disorders, in some disordered conditions of the digestive system, in diseases in which changes in the blood occur, and sometimes in cases of fatty degeneration of the heart. 2. The Quick Pulse. — In this variety each beat occupies less than the usual time, although the whole number of pulsations in a given time may not be increased. It depends on the mode of contraction of the ventricles. It is found in cases where there is great increase of nervous irritability, and also in some cases of valvular disease of the heart. The Slow Pulse is the reverse of the quick pulse. In it there is a slower contraction of the ventricles. 3. The Large Pulse is that form in which the volume is greater than usual. It depends on various conditions, and may occur either with strength or with feebleness of the pulsations. Thus, we may have the artery full in volume, but the pulsation feeble, the impulse weak, and the artery yield- ing to the pressure of the finger. We find such a condition in cases of severe pulmonary congestion. Here the fulness of the artery is palpable, but the pulsations are weak, due to excessive congestion of the pulmonary vessels. This has been termed the ' oppressed pulse,' and it is benefited by a moderate ab- straction of blood, which relieves the overgorged vessels. The Small Pulse is that form in which the volume is smaller than usual ; it may arise from feeble action of the heart, from anaemia, or from excessive tonicity of the arterial coats. 4. The Hard Pulse arises from contraction of the muscu- lar coat of the arterial walls. In this condition the artery is incompressible to the touch, and when associated with smallness of the pulse it is termed ' wiry,' or ' thready.' Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 15 We find this character in the early stages of inflamma- tions of serous membranes, such as pleurisy, peritonitis, etc. In affections which are ushered in by rigors, we find the pulse, in the first stages, small and hard, the arteries being in a state of contraction. In the second stages, sometimes called the acme of the affection, when the fever is established, the pulse changes its character, the arterioles relax, it becomes larger, but not yet being weakened, it is large and full. When the disease exhausts the patient, the pulse be- comes softer, more compressible, and short and feeble. Sometimes the hard pulse is associated with largeness, as in laminitis, which pulse is described as quick, full, and bounding. The Soft Pulse presents several varieties. The small, soft pulse is found to occur towards the end of slow, exhausting diseases ; the tension of the arteries is small, the impulse of the heart weak, and the amount of blood propelled at each ventricular contraction is deficient. We may also find this condition in some cases of anaemia. Strength and Weakness of Pulse. — For the purposes of diagnosis, prognosis, and the indications for treatment, it is important for the student to distinguish strength of pulse from a, full but feeble pulse. In a strong pulse the impulse is vigorous ; there is con- tinuous resistance to pressure, and a certain amount of fulness. On the other hand, we may find the pulse full but feeble at the same time, which is generally associated with slow action of the heart and relaxation of the arterial coats. Intermittent Pulse, — In this form of pulse an occasional Digitized by Microsoft® 16 VETERINARY THERAPEUTICS beat is missed. This may occur at regular periods and often, or at irregular periods. We must be careful to dis- tinguish between an intermittent and an irregular pulse. In the latter form the beats diifer in length, force, and character ; it is a far more serious condition, being gener- ally due to cardiac disease. An intermittent pulse may be due to individual idio- syncrasis, or may arise from indigestion or from nervous and functional diseases. It may be compatible with perfect health, and there are many animals with an intermittent pulse which never seem to be affected by it in any way. Having concluded this brief description of the varieties of pulse usually met with, we have now to consider the indications which these various forms give to the thera- peutist. • It is obvious, as previously remarked, that he cannot be too careful to avoid baste in his diagnosis, by relying on the character of the pulse, and that he has to take other symptoms into consideration in addition, if he is to ascribe the altered conditions to their real cause and prescribe suitable treatment. Thus, in the quick full pulse which usually accompanies sthenic diseases, such as laminitis, the use of sedatives and febrifuges will be indicated, such as tr. aconiti, etc., while in the full soft pulse found in the febrile stage of respiratory affections we must be careful to avoid the depleting effects of sedatives, knowing well the debilita- ting nature of such diseases, and how quickly the pulse may assume a weak character. Again, if we find a frequent small and compressible pulse, it indicates the administration of alcoholic stimu- lants, which have the effect of strengthening the weakened heart, reducing the frequency of the beats, and lessening the compressibility of the bloodvessels, Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS l7 In the various forms of pulse found in cardiac affec-- tions, both functional and organic, we shall find the use of different agents indicated, depending on the stage of the affection and its nature. We shall have to consider when stimulants are indicated, or the reverse ; also the indications for sedatives, and the value, uses, and indica- tions for heart tonics, such as digitalis. In the treatment of functional disorders of the heart, it is essential that we come to a correct conclusion as to their cause, whether due to derangements of the digestive organs or to nervous affections. All these conditions will require appropriate treatment, and also attention to dietetic measures. Symptoms connected with the Condition of the Visible Mucous Membranes. To observe these symptoms we examine the Schnei- derian mucous membrane, the mouth, the tongue, and the conjunctiva. We glean very valuable assistance from such an examination, both with regard to the condition of the patient and as an aid to diagnosis. The Schneiderian mucous membrane, in a state of health, is of a palish-red or carnation colour, which also is the condition of the conjunctiva. This condition may be altered by a variety of circum- stances ; thus, severe exercise or excitement will cause increased redness and vascularity, independent of any disease. In cases of venous engorgement and imperfect aera- tion of the blood, we find a dark, dusky hue present. In cases of acute infl.ammatory affections, such as enteritis, we find deep congestion present. When the liver is not performing its functions, either from derangement or structural changes, and the bile 2 Digitized by Microsoft® 18 VEtERINARY TBERAPEUTICS pigment is either not removed from the blood or is re- absorbed, we find a yellow tinge in the visible mucous membranes. In depraved conditions of the blood, such as exists in purpura hEemorrhagica there is noted the presence of petechial spots in the visible mucous mem- brane. In anaemia a condition of pallidity is found, and in haemorrhage this pallidity occurs suddenly. A slate-coloured appearance of the Schneiderianmucous membrane is found to exist in cases where the poison of glanders is present in the system, and it is in this mem- brane that the characteristic ulcers appear. The condition of the buccal mucous membrane also merits our attention. In cases of indigestion and dys- pepsia we find it foul and soapy, the tongue sometimes being furred, especially in the dog. This membrane is found dry in cases of febrile and in- flammatory affections, and excessively moist, due to an over-supply of saliva, in cases of irritation of the mouth and fauces. A similar condition is found to exist in irre- gularities of the teeth, and also where irritating medicines have been administered without proper dilution. The Temperature. As an aid to diagnosis, and as an indication to the therapeutist of the condition of his patient and his progress during the course of a febrile affection, too much importance cannot be attached to the information gained by the use of the clinical thermometer. In the primary stages of many affections we are enabled to recognise the serious condition of the patient, and prescribe suit- able treatment before complications manifest themselves. In some serious contagious diseases, we are enabled to recognise the existence of the specific virus in the system before diagnostic symptoms appear, e.g., pleuro-pneu- Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 19 monia contagiosa in cattle, and glanders in horses in the chronic form. Again, during the course of a febrile affec- tion, with acute inflammation of important organs, by paying close attention to the temperature in conjunction with other symptoms, we can judge with tolerable accuracy of the condition of our patient, and the results of our treatment. We know that when the temperature remains high the patient is in a serious condition, and we can also recognise the occurrence of a relapse during the progress of a disease by the appearance of a sudden rise in the temperature. In extensive surgical operations and in severe wounds, the temperature is also a useful guide, giving us an indication of the extent of irritative fever which may be present. The normal temperature of the horse may on an average be stated as 100'4°, but this is liable to variations in a small degree. It is higher in young than in adult animals, and in the very aged it may be found below the average. During the course of febrile affections, the temperature is as a rule higher in the evening than in the morning, and when possible, it is advisable that two daily observa- tions be taken. Pever. — Under the term fever are included many con- comitant phenomena besides the abnormal rise in tem- perature, such as changes in the character of the pulse, the respirations, the secretions and excretions, the ner- vous system, these changes varying in degree according to the nature of the affection of which the fever is but either a precursor or an accompanying symptom. We have also to recognise that fever may follow the per- formance of operations, or may occur as a result of wounds, when it is termed irritative fever. Digitized by Microsoft® 20 VETERINARY THERAPEUTICS Simple Fever. — That we have in the horse the occur- rence of fever, unconnected with any appreciable change in internal organs, and arising independently of any ac- companying affection, we are perfectly well aware as a result of experience. Such a condition we term simple fever. It is essentially a disturbed state of the majority of the chief functions of the body, arising from causes which we are not able to explain in a satisfactory manner. Various causes are suggested, such as sudden varia- tions in temperature, fatigue, sudden changes in hygiene and dietetics. We must, however, recognise that many such cases of simple fever, if not treated in a rational manner, or if the patients are kept at work, may develop into far more serious affections, with perhaps inflammatory changes in internal organs. The subject of fever will be again noticed under the section dealing with General Therapeutics. Symptoms connected with the Kespiratory Functions. When we consider the frequency of diseases of the respiratory system in the equine species, and the variety and importance of such affections, we see the necessity for a careful study of the symptoms under this heading. There is a close relationship between the functions of respiration and circulation in health, the proportion being about one respiration to three or four pulsations ; thus, taking the average pulse of the horse at about 40 per minute, the respirations would be from 12 to 15 in the same time. This relationship does not exist in the bovine species, especially during rumination, when the pulse may rise to 70 or 80 per minute, while the respirations may be about 10. Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 21 During exercise or exertion in a state of health this relationship is generally maintained. Thus, if the circu- lation be increased, there is a larger amount of Wood passing through the lungs requiring aeration, which is provided for by an increase in the number of respira- tions. But as a result of disease this relation is disturbed, and we may have an increase in the number of pulsations out of all proportion to the number of respirations, or the respirations may be greatly increased without a cor- responding increase in the pulsations. The indications afforded to the therapeutist by changes in the character of the respirations are various and im- portant, but we have to remember that they are not always diagnostic of respiratory affections. Thus, we may have accelerated respirations or difficult breathing in many acute diseases, due to either an altered con- dition of the blood or perverted functions of the nervous system. We have acceleration of the respirations in cases of enteritis, peritonitis, volvulus, etc., also in many cases of cardiac affection. A consideration of other symptoms, together with a physical examination of the chest, will lead us to ascribe the changes in the character of the respirations to their true cause. We may inquire as to the causes of this alteration in the character of the respirations, or, as it is termed when severe, dyspncea. These causes are various, and depend upon the struc- tures involved by the disease. Thus, in pleurisy, in the first stages we have pain, which hmits the movements of the thoracic walls, and hence impedes the respiratory movements. In the later stages, when there is effusion Digitized by Microsoft® 22 VETERINARY THERAPEUTICS into the chest cavity, there is mechanical resistance to the entrance of air to the lungs. In pneumonia and bronchitis we have the exudation causing interference with the passage of the air, and hence increased respira- tory movements are required. In affections of the larynx there may be extreme dyspnoea, from its calibre being diminished, etc. There are certain varieties of breathing which we may observe in different affections, which are of great import- ance as aids to diagnosis. 1. Abdominal Breathing. — In this variety we find that the animal endeavours to limit the movements of the thoracic walls as much as possible, and these movements are made up by the action of the abdominal muscles being brought into play ; the ribs being fixed as much as possible, there is the appearance of a hollow line extend- ing along the lower borders of the false ribs from the sternum to the anterior spine of the ilium. Such a condition is found to exist in cases of pleurisy and hydrothorax, the respirations being performed quickly and incompletely. 2. Thoracic Breathing. — In this variety the abdominal muscles are kept in abeyance as much as possible, and extra movements of the thoracic walls have to make up for the deficiency. This condition is observed in cases of flatulent colic, ascites, peritonitis, and in extensive abdominal tumours. Another variety of respiration met with is that termed irregular. We find it occurring in that affection termed ' broken wind,' where the inspiratory movement is per- formed rapidly and in a jerky manner, whilst the expira- tory is performed slowly and with a double action, especially of the abdominal muscles. "We have also to notice that symptom termed a cough.. Digitized by Microsoft® DIAGNOSIS AND GENERAL SYMPTOMS 23 A cough, although a very trivial matter in some cases, is a very important one in others. It occurs as a symptom of respiratory affections, being then generally due to some irritation of the larynx, bronchial tubes, etc., and an effort is made to remove the source of this irrita- tion, which effort is generally involuntary. A cough, however, may depend on other causes than irritation of the air-passages ; thus, we may have a cough present in cases of indigestion, intestinal parasites, etc., such a form being termed sympathetic. There are many varieties of cough met with, all being of interest to the therapeutist as an aid to diagnosis. The Moist Cough is met with in the secondary stages of catarrhal affections, and indicates that there is an increased secretion of mucus, etc. The Dry Cough presents several modifications. It is present during the first stages of catarrhal affec- tions, when the secretion of the mucous follicles is arrested. In cases of pleurisy the dry cough becomes short and painful, the forced expiratory movement causing pain. In that affection termed broken wind there is a characteristic dry cough, which is short, shallow, and suppressed, and usually single. The Chronic Cough varies in intensity, and presents modifications from that of a deep sound to that verging on to the cough found in broken wind. In that disease termed 'roaring,' the cough is deep and hollow, and in cases where cough occurs from the irritation of teething, termed a dental cough, it is loud and paroxysmal. The value of the character of a cough as an aid to diagnosis, when taken in conjunction with other symp= toms, is certainly valuable, but we must be careful to attribute it to its real cause, and prescribe appropriate treatment. Digitized by Microsoft® 24 VETERINARY THERAPEUTICS Symptoms furnished by the Condition of the Surface of the Body and Extremities. In a normal state and under ordinary conditions, the surface of the body and the extremities are of an equable temperature. In severe inflammatory diseases the general surface of the body and the legs and ears will be found extremely cold; and if, in addition, there be a cold perspiration over the body, it generally indicates a fatal termination. We find a staring coat, with severe rigors, in the pre- monitory stages of some affections ; and in cases of in- digestion, the presence of parasites in the alimentary canal, and improper feeding, there is a dry, scurfy condi- tion of the skin, which has lost the gloss and feel of health, and to which the term hide-hound is applied. Symptoms furnished by the Secretions and Excretions. In the primary stages of febrile affections there is often a diminution of all the secretions ; such a condition soon gives way to increased action of some particular organs, such as the skin, the kidneys, or the bowels. The functions of secretory organs are diminished in the early stages of inflammatory diseases. Thus, in the primary stages of pleurisy the surfaces of the pleurae are dry, there being arrest of the natural secre- tion ; as the disease continues, the secretion returns, but with a large amount of inflammatory effusion. Glands and mucous membranes are affected in a similar manner by inflammatory diseases. The condition and character of many excretions, such as those of the bowels, the kidneys, the skin, are also modified by the effects of disease, and will merit atten- tion in the section on General Therapeutics. Digitized by Microsoft® THE ACTIONS AND USES OF DRUGS 25 CHAPTER III. THE ACTIONS AND USES OF DRUGS. Befoee the student can apply the various remedies in the treatment of disease, he must be familiar with the effect which they exert on the body in a state of health • — that is, if he is to treat disease in a rational manner. By this we mean that he can give a logical reason for prescribing certain drugs, the rationale of the manner in which he expects such drugs to overcome the diseased condition, or to help nature to afford as early a restora- tion to the normal state as possible. As we shall see further on, this is not always possible, as there are some drugs which we know from experience perform certain beneficial actions in certain diseases, and yet we cannot explain in a satisfactory manner how these results are brought about. To thoroughly understand the actions of the various drugs, and their employment in the treatment of disease, the student must be perfectly familiar with the subjects of physiology, pathology, and chemistry. He must follow the actions of each drug from the time it gains an entrance to the body by the various channels, and its effects on the vital organs and systems, to the time it is expelled by the excretory organs. To do this effectually, it follows that he cannot have too much knowledge with reference to the functions of every portion of the body; and to form deductions and conclusions as to the use of such drugs in the treatment of disease, it is clear that he must possess an intimate knowledge of the changes pro- duced by disease, while to understand the complex chemical changes which often occur, an acquaintance with chemistry will be necessary. Digitized by Microsoft® 26 VETERINARY THERAPEUTICS The Action of a Drug is a certain dynamical effect which it produces on separate organs or on the various organs of the body. The actions of drugs have been demonstrated by systematic experiments on animals. The manner in which each drug is attracted to certain portions of the body, and has a special effect on various organs, and in some cases only on portions of vital systems, we cannot yet explain in a satisfactory manner. Thus, for example, we know by experiment that strychnine, no matter by what channel it enters the system, will stimulate the motor tracts of the spinal cord, and in large doses will cause violent convulsions. From a knowledge of this action we find that in small doses strychnine is beneficial in paralysis depending on imperfect action of the cord and general want of nerve tone. We know as the result of experiments that chloral hydrate has a special action on the brain, digitalis on the heart, ergot of rye on the bloodvessels and on involuntary muscular tissues, belladonna on the respiratory and cir- culatory systems and on the nervous supply of the iris, and from this knowledge we are enabled to apply these different drugs in the treatment of disease. When we have demonstrated the precise action of a drug on the healthy animal, we term it the jpliysiological action of the drug. As we shall see further on, the actions of many drugs will depend on the amount which is administered, whether in medicinal doses, in maximum doses, or in toxic doses ; also on the duration of the period of adminis- tration, and on the intervals between each dose. As a rule, we find that most drugs which act on the circulatory and nervous systems, if given in excessive Digitized by Microsoft® THE ACTIONS AND USES OF DRUGS 27 doses, will have an opposite effect to that which they produce in medicinal doses. Thus, every stimulant to the heart and circulatory system, if administered in large doses, will act as a depressant. Again, any set of nerves, if over-stimulated by large doses, will become paralyzed, as also will the nerve centres. It will also be found that drugs which act on the nervous system produce their effects by acting on different portions of it. Thus, some have a special effect on motor nerves, others on sensory ; some act on the nerve centres in the medulla and cord, others act chiefly on the sym- pathetic nervous system. All these actions will require special study when the actions of the various drugs are being treated of separ- ately. Thus we shall have to closely follow the effects of a drug in its journey through the body, from the channel by which it enters the body to its excretion by the various organs. Some act locally, such as demulcents, caustics, astringents, etc. ; others, with or without such local effects, have a remote action on organs at a distance. Most drugs administered by the mouth enter the cir- culation from the capillary vessels and absorbents of the stomach and small intestines, being carried by the mesenteric and portal vessels. Some substances make the round of the circulation in a very short space of time, as has been proved by experiment. The full effect of drugs is, as a rule, not produced until they reach the organ or tissue on which they have a special action. After remaining iu the system for a variable time, they are removed from the body by one or several of the excretory channels either unchanged or altered in their chemical composition. Digitized by Microsoft® 28 VETERINARY THERAPEUTICS During this process of excretion from the body drugs may have a special action on the channels through which they pass. We may now inquire as to the manner in which drugs are believed to act in the treatment of disease. Briefly, we may state that the adoption of the majority of reme- dies is founded on their physiological actions. The therapeiitical action is simply the physiological action exercised or modified by disease. For the purposes of description we may divide the use of remedies into two great classes: 1. Those which are intended to act aniipathically. The physiological action of such agents overcomes the morbid condition which exists by producing a condition which is directly opposite to it. Examples. — Purgatives in cases of constipation, stimu- lants in debility and depression, astringents in diarrhoea, etc. This division is more applicable to the treatment of symptoms and local diseases. 2. Those which are intended to act allopathically, i.e., such agents as, when administered, cause a short manage- able disease which overcomes the existing disease. Examples. — The use of diaphoretics in febrile cases, diuretics in cases accompanied by dropsy. This is often nature's method of recovery for example, the occurrence of diarrhoea in cases of indiges- tion, etc., due to unnatural or irritating food. By this means the ingesta producing the irritation are removed from the alimentary canal. This point is of interest to the therapeutist, as it teaches him that he must not endeavour to check this spontaneous diarrhoea immediately ; in fact, in some instances it is desirable to administer a slight laxative in order to help nature to remove the cause of irritation. Digitized by Microsoft® THE ACTIONS AND USES OF DRUGS 29 When we come to consider the actions of each drug separately, we shall find it of advantage to follow a certain line of research, commencing with the effect of the drug: on the channels of entrance to the body, the actions on the various vital systems, the various channels of excretion, and any actions on special organs or tissues. We must, as far as possible, account for the various phenomena presented, although we shall encounter many difBiculties in such a study from the complex manner in which some drugs establish their actions, while in others many points in this respect are not as yet definitely known or understood. As previously remarked, an intimate knowledge of physiology will be required in order to follow the various actions in a systematic manner, and to understand the complex effects on the different divisions of the nervous system. The following plan will be found the most convenient for the purposes of description : 1. The Immediate Local Action. 2. The Action in or on the Blood. 3. The Specific Action. 4. The Bentote Local Action. 1. The Immediate Local Action. We may subdivide this into : (a) The effects produced by the drug on the skin or exposed mucous membranes. (b) The immediate action of the drug when it reaches the stomach and intestines. Examples. — The immediate local action of belladonna, i.e., depressing the sensory nerve-endings in the skin and contracting the capillaries ; and its action when coming Digitized by Microsoft® 30 VETERINARY THERAPEUTICS in contact with the mucoua membrane of the stomach, i.e., acting as an anodyne. For other examples we may note the effect of the appHcation of cantharides to the skin, which acts as a vesicant, and the effect of sulphate of zinc when it comes into contact with the walls of the stomach, acting as an emetic. 2. The Action in or on the Blood. Most agents are absorbed into the blood from the alimentary canal, and enter into the composition of its plasma. Such substances, as a rule, have an effect in the blood and not on it, or, in other words, the blood acts the part of a conveying medium. We shall have to notice, how- ever, some exceptions to this rule, where some drugs, such as quinine, have a distinct action on the corpuscles of the blood. 3. The Specific Action. This is usually the chief action of the drug. It leaves the circulation, and is attracted to certain tissues and organs, producing some specific effects thereon. Examples. — The action of alcohol on the brain and of strychnine on the spinal cord. 4. The Remote Local Action. This is a certain effect which some drugs produce during their excretion from the system by the various excretory channels. The kidneys are the chief channels of excretion for drugs after they have passed through the tissues and organs ; next come in order the lungs, skin, bowels, mouth, and mammary glands. Such drugs are either excreted in the same form as they were adminis- Digitized by Microsoft® 0^ iPBESCRIBtNG 31 tered or in the form of the products of decomposition in the system. As these drugs pass through the excretory organs, they may exert a certain iniiuence on them, which may resemble their immediate local action. Examples. — The effect of belladonna and hyoscyamus on the urino-genital organs, which exert an anodyne or soothing effect in cases of irritation of the bladder or of the urethra. CHAPTEE IV. ON PRESCRIBING. When the student has become perfectly familiar with the various actions of the different drugs, and their appli- cation for therapeutical purposes, based on a knowledge of such actions, he will then be in a position to utilize the different agents for the treatment of disease, the art of which is termed prescribing. When this is attempted for the first time, he will find it rather a difficult matter. He must select an agent, out of a large number at his command, which will best meet the exigencies of his case, and in such a selection he must pay attention to many important details. The art of prescribing may be most conveniently studied under the following heads : 1. The Selection of the Bemedy. 2. Contra-indications. 3. Idiosyncrasy. 4. The Circumstances ■ which modify the Action of Medicines. 5. Combinations — Chemical and Physiological In- oompatibles. 6. The Prescription. Digitized by Microsoft® 32 VETERINARY THERAPEUTICS 1. Selection of the Remedy. The selection of the remedy is the most important part of the art of prescribing. The nature of the disease must be carefully studied, and a drug selected which possesses actions suitable for our purpose, but which must not possess other actions that may be detrimental to the case. This leads us to a consideration of the second heading in our list, viz. : 2. Centra-indications. We say that a certain drug is contra-indicated in certain diseases, when we are aware that it produces effects which would be prejudicial to the cases, although it might possess one action which would be of service ; for example, we say that opium is contra-indicated in diseases of the respiratory organs with shallow, embar- rassed breathing, also in congested and inflammatory conditions of the brain and in affections of the kidneys. Again, purgatives are contra-indicated in inflammatory conditions of the intestines, and depressant remedies are contra-indicated in all typhoid and debilitated cases, and irritating diuretics in cases of nephritis. The contra- indications of the various drugs will be noticed when we consider the therapeutical value of each medicinal agent. 3. Idiosyncrasy. By this term is meant a peculiar susceptibility which some animals possess to the action of certain medicines. In the majority of instances this means increased sus- ceptibility, though we sometimes meet with the reverse. Examples. — Purgatives. Some horses are very severely affected by even a moderate dose of aloes, which may even go into superpurgation ; on the other hand, we meet with cases where the medicinal dose has little or no effect. Digitized by Microsoft® ON PRESCRIBING 33 We also meet with instances where there is great sus- ceptibility to the action of nux vomica, the physiological effects being produced by even medicinal doses. Amongst other examples may be noticed the susceptibihty of some horses to the action of blisters, and the peculiarities of action of opium, and its alkaloid morphia, in different individuals. 4. The Circumstances which modify the Action of Medicines. These are most important to the student, and will re- quire a detailed consideration. We will notice them under the following heads : (a) The Modes and Forms of Administration of Drugs. (6) The Species of Animal. (c) Age and Size. (d) The Effect of Diseases. (e) The Dose. (/) Frequency. {g) Time. (h) Duration, Toleration, Habit, Accumulation, (i) The Effect of Climate and Surroundings. (a) The Form and Mode of Administration of Drugs have an important effect in modifying the effects of the drugs in the system. The more soluble the preparation, the more quickly it is absorbed and produces its specific effects. There are varieties of preparations of each drug, which will be noted when dealing with the special therapeutics of each, some having decided advantages over others. There are many ways of introducing drugs into the system, some very commonly employed, others only 3 Digitized by Microsoft® 34 VETERINARY THERAPEUTICS occasionally. Some are not intended to be absorbed, but to act only locally, such as gargles, insufflations, local anaesthetics, and local anodynes. 1. By the skin, or mucous membrane continuous with the skin, either rubbed in or painted on the surface, or applied in the form of dry powder. Usually only a local effect is desired, but some may become absorbed. Examples. — Gargles to the throat ; insufflations to the nasal cavities and facial sinuses ; liniment of belladonna applied to painful parts ; cocaine as a local anaesthetic J the use of atropia in inflammatory conditions of the eye ; and the various collyria employed. 2. By the mouth, both in some cases to act locally on the stomach and intestines, and to be absorbed into the system chiefly from the stomach and duodenum. We may administer medicines by the mouth in various ways, in the form of either balls, drenches, powders, or electu- aries. The form of electuary is convenient when it is found either dangerous or impossible to administer the other forms. Thus, in cases of acute laryngitis, there is great danger in the administration of drenches ;, from the irritable condi- tion of the throat, there is a risk of the animal struggling and the fluid entering the trachea and bronchial tubes. In such cases we can place the medicinal agent in the form of an electuary between the molar teeth, when it will not only become absorbed, but in the case of such agents as belladonna, potass, chlor., etc., there will also be a beneficial local effect produced. Again, in cases of tetanus, we cannot administer remedies in the usual manner, and we find the form of electuary very valuable. We may also refer to the administration of ol. crotonis as a quick and effectual purgative in cases where others Digitized by Microsoft® ON PRESCRIBING 35 cannot be administered ; this agent will produce its effect when placed on the tongue. 3. By Subcutaneous or Hypodermic Injection. — In this method the active principle of the drug in solution is introduced under the skin or into the subcutaneous tissues by means of a syringe and hollow needle. It con- stitutes the quickest and surest mode of bringing the system under the influence of a drug. By this means the active principle at once gains entrance to the circulation, and produces its specific effect with certainty and rapidity. The introduction of the agent is simple ; the bulk of fluid should be as small as possible, and should be pre- pared so as not to irritate the tissues. The part selected should be one where the skin is loose and thin, such as that of the chest or neck. A fold of skin is taken up, the needle is then pushed into it, and the fluid forced in by the syringe. After the completion, the part is gently manipulated, so as to favour the absorption of the fluid. Mishaps may occur by reason of the solutions being irritant or too large in bulk, or the syringe and needle not being perfectly aseptic ; in such instances irritation, abscess, and sloughing may occur. The hypodermic method is of great value in veterinary practice, as it ensures the full action of the drug, and is easily applied in cases where other means would not be practicable, or where the drugs would take too long a time to act. In cases of violent abdominal pain it is often impossible to administer medicines by the mouth, and much of the dose is lost ; also in cases of inflammation of the intes- tines there is very little power of absorption from the alimentary canal. Digitized by Microsoft® 36 VETERINARY THERAPEUTICS 4. Intravenous Injection. — By injecting the agent direct into the venous system, it produces its effects very quicldy ; but this is a method rarely adopted for thera- peutical purposes, as its drawbacks are more than its advantages. No irritating substance can be used in this manner, nor any substance which has the power of coagulating albumen. 5. Intertracheal Injection. — The respiratory mucous membrane possesses very rapid powers of absorption, as has been proved by experiment. The injection of medicines into the trachea is practised in cases of that parasitic disease termed ' husk,' or ' hoose,' in cattle, where the object is to act directly on the parasites. A mixture containing turpentine and other agents is employed for the purpose, and is introduced into one of the spaces between the rings of the trachea. Any irritating fluids which gain entrance to the bron- chial mucous membrane cause great respiratory distress, and may cause mechanical bronchitis or pneumonia. It is said that fatty oils are not absorbed by the bronchial mucous membrane, but are rejected by the trachea and nostrils. These points are of importance when administering fluids to horses or cattle in the form of drenches, as it may happen, from keeping the head too high, from the struggles of the animal, or from laryngitis, that a portion of the fluid may find its way down the trachea, and cause a very serious condition of the animal. 6. By Inhalation. — By this method volatile substances are intended to enter the blood from the pulmonary capillaries, or to act on the bronchial tubes and bron- chioles. As examples of the former we have the inhalation of chloroform and ether as general anaesthetics, and of the Digitized by Microsoft® ON PRESCRIBING 37 latter we have the inhalation of steam, medicated with various disinfectant and soothing remedies, such as ol. eucalypti, creolin, etc.— of great value in cases of bronchitis, lessening irritability, softening the exudation, and preventing decomposition therein. {b) The Modifying Effect of Different Species of Animals on the Action of Medicines. — Briefly, the species of animals which we are called upon to treat are horses, cattle, sheep, pigs, and dogs. "We shall have to consider carefully the differences in action of the various medicinal agents in these different species, such differences mainly depending on special arrangements of certain vital systems in each. There is only a slight difference in the arrangement of the circulatory and respiratory systems in these various species ; consequently, the action of medicinal agents is tolerably uniform on these systems. In the nervous, digestive, and cutaneous systems, how- ever, a marked distinction exists in the different species, so that the action of drugs on these systems is consider- ably modified according to the species to which they are administered. We may take it as a rule that the more highly developed a system or aa organ is, the greater will be the effect of agents which have a specific action on it. Thus, opium and its alkaloid, morphia, which in the highly-developed cerebrum of man causes deep stupor in large doses, acts in the horse as a motor excitant, causing the animal to walk round and round the box in one direction, and in some oases violent delirium occurs. In the horse we have many physiological peculiarities to notice, especially with reference to the digestive system. The stomach is small, and the intestines very capacious, and, according to the results of experiments, there is little or no absorption from the stomach. Digitized by Microsoft® 38 VETETtTNARY THERAPEUTICS The arrangement of the mucous membrane of the stomach is peculiar, the cuticular portion being a con- tinuation of the membrane of the oesophagus; and this portion does not secrete gastric juice ; the villous portion secretes the true digestive juice. There are other peculiarities, such as the inability of vomition in the horse, and the presence of lactic acid instead of hydrochloric in the gastric juice. These will be again referred to in the section dealing with the general therapeutics of this system. In the horse the excreta carry away about two-thirds of the water of the food, while in dogs only 5 per cent, is got rid of in this manner. In herbivora only 30 per cent, of the water escapes by the kidneys, while the amount in carnivora is 70 percent. In herbivora 70 per cent, of the water is removed by the lungs and skin, while in carnivora only 30 per cent, escapes in this manner. Vegetable purgatives act better than mineral in horses, the latter being very uncertain. The purgative generally resorted to is aloes, which acts chiefiy on the large intestines. Emetics have no action in the horse, even when given in large doses; some may appear to have a sedative effect. The kidneys are easily acted on by diuretics, but the skin is not so readily acted on as in man, so that to enable diaphoretics to produce their effect, the animal must be warmly clothed, otherwise the agents will pass off by the kidneys acting as diuretics. The horse is very insusceptible to the actions of seda- tives. Many drugs which produce a sedative and soporific effect in man act in this animal as cerebro-spinal ex- citants, even when given in large doses. Digitized by Microsoft® ON PRESCRIBING 39 In cattle we find great differences to ezist with regard to the actions and doses of medicinal agents as compared with the horse. These animals are usually of a dull, phlegmatic tem- perament, and possess a peculiar arrangement in the alimentary canal ; the stomach is divided into four com- partments, of which only the fourth division is capable of performing the function of digestion. The first division, termed the rumen, is of enormous size, and capable of holding a large amount of ingesta. The intestines are small in proportion, and we may remark that affections of this portion of the alimentary canal are rare compared with those of the stomachs, which are a fruitful source of disorder in ruminants. Very large doses of purgatives are required to produce an effect, of which saline purgatives largely diluted prove most beneficial. Large doses of stimulants and tonics are also required in these animals ; the skin and kidneys are not readily acted on, and they are not susceptible to either the ex- citant or soporific effects of opium or its alkaloids to any extent. We have to consider that in many cases of serious affections in cattle it is often more advantageous to have the animal destroyed for the butcher than to have the owner run the risk of expense, and to have the animal die of the disease. Taking into consideration the usual value of cattle, we should be careful to avoid administer- iug substances which are likely to impart a disagreeable flavour to the flesh, such as ether, oil of turpentine, etc. "With reference to sheep, similar observations will apply ; they usually take aboub one quarter the doses of cattle. Dogs resemble man to a certain extent. The alimentary canal is short and straight, and easily affected by purga- Digitized by Microsoft® 40 VETERINARY THERAPEUTICS tives, of which a combination is preferable to a large dose of a single purgative. The stomach is readily acted on by emetics, and the act of vomition is very easily produced in this animal ; thus, dogs by instinct obtain a certain grass, which has an emetic effect, when they feel deranged from any source of irritation in the stomach. In prescribing medicines for dogs, it is necessary to bear in mind that the agents used should be as palatable as possible, in order to avoid the risk of having them ex- pelled from the stomach. Although in many instances dogs take similar doses of medicinal agents as man, still there are notable excep- tions. For example, they will take very large doses of aloes as compared with man, and very small doses of calomel and oil of turpentine as compared with him. Pigs are similar to dogs in their peculiarities to the action of medicines, of course making allowance for increase of doses on account of their increased size. (c) The Influence of Age and Size.- — As animals of each species vary very much in size, it is necessary to remember that, as a rule, the smaller the size the more diminutive should be the dose. Young animals are more readily acted on by medicines than adults, and in very old animals medicinal agents have a greater effect, as the vital organs become weakened by age. We may remark that the alimentary canals of young animals, such as foals and young dogs, are very susceptible to the action of purgatives, and that only the mildest forms and moderate doses should be employed. {d) The Effect of Diseases on the Action of Medicines. — In cases of fever the arterial tension is altered, and Digitized by Microsoft® ON PRESCRIBING 41 absorption is retarded. In cases of inflammation of the stomach or intestines, the absorption of drugs is retarded, and the severe pain which accompanies such affections resists the action of anodynes and soporifics. Thus, in cases of enteritis very large amounts of drugs, such as morphia, etc., will be tolerated with very little effect. In cases of hyper- secretions, such as diarrhoea, polyuria, elimination is hastened, and drugs such as opium and alcohol have only a slight effect. When the secretions are diminished, we observe the effects of the accumulation of a drug in the system. In cases of affections of the kidneys, where the ex- cretion of urine is diminished, drugs which are carried away from the system by this channel are likely to be retained if administered in repeated doses, and may exert a sudden effect. In excessive nervous derangement, such as tetanus, very large doses of nerve sedatives are tolerated. Affections of a debilitating nature do not stand the action of sedatives or depressants well, and such remedies should be avoided. (e) The Dose. — This is a very important portion of the subject under consideration, and one that can only be studied practically. The dose, or the amount of any drug which it is safe or advisable to administer to any patient for therapeutical purposes, depends on the variety of circumstances that we have just described. The quantity of any drug given will have a material effect on its action. Thus, small doses of the salts of magnesia are alterative and diuretic, while large doses are purgative. Aloes is a tonic in small doses ; in full doses it is an active purgative. The proper doses can only be learned by experience. Digitized by Microsoft® 42 VETERINARY THERAPEUTICS as we have seen that they depend on so many circum- stances, and also on individual peculiarities and tempera- ments. The doses generally laid down are the smallest useful doses which it is safe to begin with ; there are many affections, however, in which it is necessary to administer drugs in such doses that their physiological effects will be produced before any therapeutical results will be obtained. As previously stated, the age of the patient must be taken into consideration. With reference to horses, we may calculate roughly that yearlings require one-third of the dose for an adult, two-year-olds half the dose, and three-year-olds two-thirds. With reference to dogs no fixed rule can be laid down, as so much depends on the size and breed. We may, however, state that in most cases it is safer to prescribe small doses when treating one of these patients for the first time. With regard to purgatives, both for horses and dogs, a proper dose should be given, and if a sufficient amount of purgation is not produced, the agent is kept in the system longer than necessary, and much nausea results. (/) FrecLuency. — We prescribe medicines to be given either in a single dose or to be repeated in certain doses at certain intervals. Thus, purgatives are generally given in one dose, tonics twice a day, febrifuges and stimulants at short intervals, so as to keep up their effect, and so that the effects of one dose will not have passed away before the next is given. (g) Time. — We take advantage of natural tendencies in order to assist the action of drugs. Thus, alkaline stomachics are given before feeding to increase gastric secretion. Acid stomachics are given after feeding, when Digitized by Microsoft® ON PRESCRIBING 43 the natural acid is deficient. Drugs which have a tendency to irritate the mucous membrane of the stomach are administered either along with the food or immediately after feeding. Example. — Arsenic. Some require a special preparation of the alimentary canal before administration. For example, purgatives^ in which it is essential that the horse be properly pre- pared by being kept on bran mashes for a reasonable time beforehand, so as to have the intestinal contents in a soft condition. When prescribing iodine, we must be careful to administer it at a proper interval between the times of feeding in herbivorous animals, so as to avoid the insoluble iodide of starch being formed, as the food of such animals contains a large proportion of starch. Qi) Duration, Toleration, Habit, Accumulation. — The length of time during which a drug may be administered depends on circumstances. There are some drugs which, after administration to the same individual for a certain time, commence to lose their characteristic effect, and the system can be made to resist even very large doses — in fact, such doses as would have a toxic effect in other individuals ; examples of such drugs are opium and arsenic. We may remark that, in prescribing arsenic, we have to commence with small doses, and to gradually increase them as the system of the patient gets accustomed to its effects. By accumulation we mean to infer that there are certain drugs which, when given in repeated doses for a period of time, may not produce any'appreciable effects at first, when after an indefinite period of administration they may suddenly exert their physiological effects in a marked degree. Such drugs are said to be cumulative, examples of which we find in digitalis, mercury, strych- Digitized by Microsoft® 44 VETERINARY THERAPEUTICS nine, etc., and in prescribing these we must be careful that they are not allowed to enter the system more quickly than they can be excreted. (i) The Effect of Climate and Surroundings. — Narcotics are said to act more effectually in hot than in cold climates. Chemical reactions and the protoplasmic move- ments are facilitated by a slightly elevated temperature. In damp, humid climates the animal system becomes relaxed and out of tone ; hence smaller doses of drugs are borne than in dry, bracing climates. The effect of surroundings has a material bearing on the subject of prescribing ; horses kept in badly ventilated and over- crowded stables are generally prone to diseases of a debilitating or typhoid nature, and do not stand depletive measures. Well-bred animals in good condition and in proper surroundings, when attacked by acute inflam- matory diseases, bear depletion well, and the effects of sedatives are beneficial. In canine practice we must be careful in distinguishing the varieties of patients in prescribing ; for example, the pet dog, always accustomed to an indoor life and the excesses of the table, will require different treatment to the sporting dog, or one accustomed to an outdoor life in the country. Having concluded the description of the circumstances which modify the actions of medicines, we will now con- sider the fifth important section of the art of prescribing, viz. : 5. Combinations— Chemical and Physiological Incompatibles. It is often found of advantage to combine one druo- with another in a prescription, so that one will increase the action of the other, or neutralize any unpleasant Digitized by Microsoft® ON PRESCRIBING 45 effects. To effectually combine drugs we must be per- fectly acquainted with their chemical composition and properties, and also with their physiological actions. In the combining of certain drugs, chemical reactions may occur, and either a useless or dangerous compound may be formed. Such drugs are said to be chemically incompatible with each other. There are some incom- patible drugs, however, which we do combine, but we are aware of the actual compound which is formed, and which suits our purpose. For example, the familiar white lotion, so useful as an astringent application, is, technically speaking, incom- patible, being composed of a mixture of acetate of lead and sulphate of zinc in water, the result being the formation of acetate of zinc in solution, and the sulphate of lead, which, being insoluble, is thrown down as a white precipitate. Persalts of iron are incompatible with sub- stances rich in tannin, such as cinchona, etc. Chlorates should not be prescribed with iodides, as a chemical change occurs which may cause irritation of the stomach. There are many other examples of chemical incompati- bles which the student will learn when at practical work in the pharmacy ; his knowledge of chemistry will teach him that acids should not be combined with alkalies or vice versa. Attention must, however, be drawn to the danger of mixing substances which are likely to cause an explosive mixture. Thus, chloride of lime mixed with sulphur forms an ex- plosive compound. Oil of turpentine and sulphuric acid is also dangerous, and the same may be said of chlorate of potash and sulphur. Other examples are permanganate of potash and Digitized by Microsoft® 46 VETERINARY THERAPEUTICS cbromio acid, mixtures of chlorine with ammoniacal salts, nitrates with organic bodies, etc. The chief incom- patibles will be mentioned under the heading of each drug in special therapeutics. By physiological incompatibles we mean those drugs which neutralize the effects of each other in the system ; such agents are also termed physiological antagonists. For example, the action of strychnine on the motor tracts of the spinal cord and of Calabar bean on the same region is antagonistic, the former stimulating, the latter depressing and paralyzing, the same region. Advantage is taken of the knowledge of the actions of antagonistic drugs to form reliable antidotes in cases of poisoning. There are some drugs which, although physiologically incompatible as regards certain actions, are useful to combine in therapeutics. Thus, morphia and atropia are antagonistic as regards their action on the pupil, but are very useful in combina- tion as sedatives and anodynes. We also employ some drugs which are antagonistic to a slight degree to over- come certain unpleasant effects, such being termed cor- rectives. 6. The Prescription. As a result of the consideration of the preceding sections, the student will now be able to combine the remedies which he judges will be of benefit to his patient, the writing of which in a handy and legible form for the dispenser is termed the prescription. Prescriptions should contain as few drugs as possible, as it is an irrational proceeding to combine a number of these agents, without paying attention to the specific action of each. The classical prescription is forined on certain definite lines, as' follows ; Digitized by Microsoft® ON PRESCRIBING 47 1. The Basis ; that is, the selection and form of prepara- tion of the drug which it is intended to employ. The selec- tion of the drug is the most important part of the pre- scription, as this is the chief portion of the combination which is to produce the special therapeutical effect. 2. The Adjuvant. — This is the addition of some agent which is intended to assist and hasten the action of the basis. 3. The Corrective, which limits or modifies the action of the basis, and prevents unpleasant effects. 4. The Vehicle or Excipient. — This is some substance added so as to have the preparation in a convenient form for administration. Example of a Classical Prescription. R. Aloes Barb., 3v. Ext. belladonnse, 3ss. P. zingiber, 3ii- Theriacee, q.s. Ft. bol. i. In this, which is a formula for a purgative ball for the horse, the aloes is the basis; the belladonna is the adjuvant, as it increases the action of the aloes ; the ginger is the corrective, as it prevents griping ; and the treacle is the excipient, or vehicle in which the substances are mixed so as to make a bolus of proper consistency. We may remark, however, that there are few prescrip- tions written according to these fixed rules, as in many instances the basis and the vehicle or excipient are only prescribed. The subject of prescription-writing will be again referred to in the addendum on veterinary pharmacy. Digitized by Microsoft® PART II. GENERAL THERAPEUTICS. CHAPTBE I. INTRODUCTORY. The subject of general therapeutics includes a considera- tion of the evidence of the usefulness of therapeutic measures, the rationale of their operation, and the indica- tions for their employment. We shall find that it is impossible to lay down strict rules for the application of therapeutical measures ; all that can be done is to present a careful consideration of general principles, with the important points in their application. And to have this application successful requires special knowledge and sound judgment and reasoning. We may inquire as to how the facts and principles of general therapeutics are obtained. We may answer this by stating that these principles are the result of experiment and of experience, and a knowledge of the physiological action of drugs. Experience, although valuable as regards the utility of a particular method of treatment, is open to ob- jection. It is founded on certain experimental evidence either of the beneficial effects of a certain method of treatment, in the course and termination of a series of cases of the same disease, or to the immediate effects of Digitized by Microsoft® INTRODUCTORY 49 certain treatment, irrespective of the termination or duration of the diseases. The former evidence is open to objection, because we know that no two series of cases of a disease are exactly alike in all particulars, but depend on many circumstances, such as the severity of the disease, the constitution of the patient, the existence of complications, etc. It does not follow that because a certain line of treat- ment is beneficial in a certain number of cases that it should be so in individual cases. The practitioner should endeavour to deal with cases of disease individually, and not in the aggregate. Nevertheless, we must admit the value of the results of experience, in order to test the therapeutical value of medicinal measures. Methods of treatment may be originated by a study of the physiological action of drugs, but the practical test is afforded by experience. We are also aware that our knowledge of many impor- tant remedies was acquired altogether by experience, before we were able to explain the rationale of their actions, and that even in the present day we are pre- scribing some remedies with success, while we cannot in a satisfactory manner explain their modus operandi. However, the number of such remedies is gradually decreasing as we are improving our knowledge of phar- macology, physiology, and pathology. General therapeutics may be said to depend on four considerations, which may be designated as follows : (1) health; (2) pharmaco-dynamics — physiological action ; (3) pathology ; (4) recovery. (1) Health. — The term ' health ' is not a definite one ; that is, it does not signify any fixed or unchangeable con- dition of the body. 4 Digitized by Microsoft® 50 VETERINARY THERAPEUTICS There are many degrees or gradations of health to which we cannot a,pply the terms disorder or disease. The physiological state of the body is no.t a constant one ; it is capable of being acted on by various surround- ing influences, which influences are themselves constantly changing, such as temperature, air, food, etc. Thus, country horses can thrive on a different quality of food, and in different surroundings, to what those in well-kept stables in town are accustomed to ; but it is possible to get animals accustomed to these different influences. We have also to consider that it is possible to have certain changes in organs which are not vital, without any appreciable alteration in what we term the health of the animal. In veterinary practice it is impossible to determine definitely in many instances the exact period at which there is a departure from the normal state and the commencement of disorder or disease, as our patients are incapable of the powers of speech, and the first symp- toms have to be noticed by the attendants, who are not always gifted with keen powers of observation. Except in cases which are characterized by the appear- ance of pain, the usual symptoms first noticed by the attendants are dulness and loss of appetite, etc., and it is quite clear that many affections will be in a definite stage of development before such cases are brought under the notice of the practitioner. (2) Pharmaco-Dynamics — Physiological Action. — We possess a certain power of interference over the physiolo- gical state of an animal. We can alter the character of the food and the system of feeding ; we are able to modify his surroundings in the way of ventilation, etc. ; we can order exercise or keep him at rest ; we can apply clothing to the body ; and lastly, we can introduce into his system certain medicinal agents to modify or Increase Digitized by Microsoft® FOUNDATIONS OF RATIONAL TREATMENT 51 the functions of certain organs. This power or control we terra acting ^physiologically on them by such means, and the action thus exerted we term. & physiological action. The science which relates to the power of modifying physiological activity we term pharmaco-dynamics. (3) Pathology. — It is difficult to draw a hne between health and disease, as we cannot recognise a definite state for the former term. It is also difficult to separate in- fluences into physiological or iato morbid or pathological. The change from what we are accustomed to recognise as health, when sufficiently definite, we term disorder, or when more marked and attended with decided suffering, disease. (4) Recovery. — This is the aim of the therapeutist, and in this direction he is ably assisted by nature, and it is of the greatest importance in treatment to imitate and help such efforts of nature, and not to retard them. The body possesses certain provisions not only for re- covering from the effects of disease, but also for preventing disease. We have to consider that in veterinary practice we have to ascertain as definitely as possible whether our patients will recover in such a manner as to be of prac- tical utility to their owners. Of course, in the case of dogs used as companions or pets, such a consideration may not be so necessary, but in horses and cattle it is of supreme importance. If a horse is suffering from a chronic affection, which is liable to be continuous or to recur frequently, so as to practically unfit him for work, all our efforts to sustain life will be of no benefit, as after a long and expensive illness he would be of no benefit to his owner, but a source of loss. The same may be said with reference to the majority Digitized by Microsoft® 52 VETERINARY THERAPEUTICS of cases of fractures, except in animals such as brood mares, or mares which can be so utihzed. In horses, in consequence of the difficulty experienced in keeping the fractured limb in a state of repose, com- plications are apt to ensue, and such a condition of the limb may be brought about that the animal will be un- fitted for any work, and the most humane proceeding will be to have him destroyed at the commencement. In cattle, if there is no reasonable chance of the animals recovering, or of their being fattened for the butcher, immediate destruction must be resorted to, as not only is there the expense of treatment to no purpose, but also the risk of the medicinal agents injuring the quality of the meat, besides the loss of condition, which soon leaves the carcase of no value. We may also refer to diseases not only incurable, but also dangerous to other animals and to mankind, by reason of their contagious nature, such as glanders, rabies, etc. Here treatment is out of the question, and com- pulsory slaughter becomes the most beneficial measure. In canine practice, however, with the exception of rabies, the majority of diseases among favourite animals require the skill of the practitioner, without the same consideration of practical utility in the event of recovery. There are six means which the body possesses by which variation of functional activity can be secured and morbid influences can be met and overcome. These natural means of recovery are of the greatest importance to the therapeutist, as by a consideration of them he is enabled to prescribe a line of treatment best suited to the indica- tions of a case. 1. Reserve Force. — The body possesses a certain amount of latent force which is called into action when it is re- quired ; this is termed reserve force, and we have examples Digitized by Microsoft® NATURAL MEANS OF RECOVERY 53 in the increase of size of muscles when they are con- stantly called into action, and also in the heart, which possesses reserve force when required for great exertion. 2. There is a Power of overcoming the Cause of Disorder. — Thus, if the reserve force is being constantly called into action, the result will be enlargement or hypertrophy of tissues or organs. We have examples of this in hyper- trophy of the left ventricle, when it has extra work to perform in cases of some valvular lesions. This is termed compensation. Also in enlargement of one kidney when the other is diseased. 3. The Cause of the Disorder may be expelled by Kegu- lating Mechanisms. Example. — The occurrence of vomition in the dog when the stomach is overgorged with food, or of purgation when the presence of irritating ingesta irritates the intes- tines. 4. Vicarious Compensation. — This occurs where, in certain affections, one organ endeavours to perform the work of another ; for example, in cases where the func- tions of the kidneys are suspended, the urea accumulates in the blood and is excreted by the skin and intestines. This may be taken as an effort to remove the effects of a disorder. 5. Nature has a power of insuring rest, e.g. the loss of appetite seen after a case of engorgement of the stomach, which gives that organ a necessary rest. 6. By Repair. — ^When anatomical changes have oc- curred as- the result of disease, we find that nature pos- sesses the power of repair to a certain extent by means of an increase of nutritive activity. There are four foundations of Rational Therapeutics which will now engage our attention, and are of great importance. Digitized by Microsoft® 54 VETERINARY THERAPEUTICS 1. The organs of the body act in obedience to surround- ing natural forces. 2. We have a certain power of controlling or modifying these natural forces. 3. We regard disorder or disease as the result of some disturbing influence acting on glands, tissues, or organs ; the phenomena produced are what we would expect in those affections of which we have a tolerably accurate knowledge of their pathology. 4. The functions of organs, and even the anatomical state, if the disease is not too far advanced, will return to the normal if the influences become normal. These are all very important considerations to the therapeutist, as they indicate to him that he must take advantage of these numerous natural forces in his treat- ment, and endeavour to promote a return to the normal state by acting in accordance with these forces as much as possible, or, when necessary, by neutralizing or coun- teracting the effects by the employment of other forces. Diflferent Kinds of Treatment. We will now consider the various kinds of treatment in a general manner : 1. Preventive Treatment. — Hygiene is the science and art of preserving health, and, as will readily be seen, it is founded on an accurate knowledge of physiology. Prophylaxis recognises the causes of disease at work, and avoids or counteracts them by every possible means. Infection may be guarded against by avoiding all sources of it ; by the system of preventive innoculation, or by the administration of certain drugs, which have the effect of rendering the system capable of resisting the action of the morbid influence ; for example, the adminis- Digitized by Microsoft® DIFFERENT KINDS OF TREA TMENT 55 tration of sodii hyposulphis as a preventive of dis- temper in the dog. 2. Immediate Treatment. — This includes the Removal of the Cause, attention to dietetics, and the use of medicinal agents. For example, in eases of indigestion, due to engorge- ment of the stomach, we remove the indigestible food from the stomach by the administration of an emetic in the dog, and a purgative in the horse ; we destroy and . remove parasites in the intestinal canal by means of vermicides and vermifuges. This is nature's third method of recovery. 3. Symptomatic or Palliative Treatment. — This is nature's fourth method of recovery. If we are unable to remove the morbid cause at work in the system, we must neutralize or correct its effects in the body. This is, of course, not so desirable a method as that just mentioned, as we are now treating the effects instead of removing the cause. We select such remedies as act in an opposite direction to the effects of the morbid cause. 4. Expectant Treatment. — In this form we treat the symptoms presented to us before the disease is fully developed, and before it is possible to form an accurate diagnosis. 6. Rational and Empirical Treatment. — Rational Treat- ment is that which is founded on chemical, physiological, and pathological knowledge, and on a consideration of the powers possessed by nature, which we have described. Empirical treatment is founded on the results of ex- perience, and is not guided by any laws ; but we must remember, as previously stated, that many of our most valuable remedies were prescribed in this manner in former times, and their value ascertained hj the sta,tistics of recoveries, Digitized by Microsoft® 56 VETERINARY THERAPEUTICS As our physiological and pathological knowledge ad- vanced, and also the subject of pharmaco-dynamics became better understood, a large number of such remedies were entitled to be placed under the heading of rational treat- ment, and the tendency of the present day is to make empiricism give way to rationalism, and thus render therapeutics a perfect science. As well expressed by Bouchard, ' the indications for the future of rational therapeutics will be realized when physiological thera- peutics is controlled by statistical. In the next series of chapters we will consider the general therapeutics of the different vital systems of the body, and for convenience of description, and as explain- ing the rationale of treatment, each system will be noticed under five sections, as follows : 1. A brief description of the physiological relations of the system in the horse, cow, and dog. 2. The pharmaco-dynamics of the system, and also the use of non-medicinal measures when required. 3. The pathological relations of the system — disorders and derangements being selected, rather than actual dis- ease of the parts, so as to illustrate the actions and uses of remedies. 4. Natural recovery — notice being also taken of the limits of treatment. 5. Rational therapeutics — which will be founded on the four preceding sections. Digitized by Microsoft® DIGESTION— THE MOUTH 67 •CHAPTBE II. DIGESTION— THE MOUTH. I. Physiological Relations. The process of digestion commences with the reception of the food into the mouth, where it is triturated and mixed with saliva and mucus, and the starchy consti- tuents partly converted into sugar. The duration of mastication varies in different species of animals. The movements of mastication in carnivora are confined to tearing the food into pieces small enough to be swallowed. In herbivora a much longer time is required, and the food has to be reduced to a condition of fine comminu- tion. ' In the horse the food must be thoroughly macerated before reaching the stomach, hence the duration of mas- tication will be longer than in the ruminant, where the food is acted on in the rumen and remasticated in the mouth. 1. Food. — The subject of food is a most important one, and will require special study. The student is referred to ' Veterinary Hygiene,' by Professor P. Smith, and to ' Veterinary Physiology,' by the same author, for valuable information on all the details of dietetics. 2. The Flow of Saliva. — This is the result of nervous influences. Afferent nerves convey sensations to the medulla from the mouth, viz., the gustatory division of the fifth, and the glosso-pharyngeal. The impulse is then conveyed to the glands by efferent nerves, and secre- tion results. Digitized by Microsoft® 58 VETERINARY THERAPEUTICS The submaxillary gland is supplied by the chorda tympani, which supplies dilator fibres to the vessels, and secretory fibres to the gland-cells. It is also supplied by a branch of the sympathetic, which gives constrictor fibres to the walls of the artery supplying the part. The nerve supply of the parotid consists of the glosso- pharyngeal and the sympathetic. 3. The sensory nerves of the mouth receive and transmit to the cerebrum and medulla the impressions of taste, whether bitter or sweet ; these impressions are trans- mitted to a special centre in the medulla, from which they are reflected to the stomach, modifying its functions, and to the salivary glands of the mouth, which they in- fluence through the chorda tympani. II. Pharmaco-dynamics. 1. Food. — We can alter the quantity and quality of the food, and the form of the food ; thus, we can order the oats to be crushed or the hay to be chopped, as we may see desirable for different cases. 2. We can influence the sensory apparatus of the mouth by the administration of aromatic bitters, by the mem- bers of the spirituous group, and by acids. Aromatic bitters increase the relish for food by stimu- lating the secretion of the digestive fluids in the mouth and also in the stomach, as will presently be described. These increase the relish for food, and provide for the digestion of the same by an increase of the digestive fluids of the mouth and stomach. Examples. — Aromatic oils, gentian, quassia, etc. Sialagogues increase the secretion of saliva. These in- clude the greater number of stimulants of the sensory apparatus, diluted mineral acids, and vegetable acids. Digitized by Microsoft® DISORDERS OF THE MOUTH 59 We divide sialagogues into those which act locally by being absorbed and acting on the gland structure directly, and specific sialagogues, •which act on the terminations of the nerves in the salivary glands, or on the cells them- selves, by whatever channel they enter the system. As examples of ordinary sialagogues we have dilute mineral acids, vegetable acids, and their salts, etc., which have the effect of removing thirst. As examples of specific sialagogues we have jaborandi and its active principle pilocarpine, mercury, iodine, and physostigma. Indirect emetics, such as antimony and ipecacuanha, also act as sialagogues. Anti-sialagogues are those drugs which diminish the secretion of saliva, such as dilute solutions of alkalies, as potash and soda. Specific anti-sialagogues act upon the secretory nerves, such as belladonna and its active principle atropine, also opium in excess. Demulcents are substances which afford an artificial covering to the mouth, tongue, and fauces, when the natural secretion fails. Uxmnples. — Mucilaginous preparations, linseed-tea, gums, honey, syrups, etc. III. Pathological Relations. 1. In the food we find the chief cause of digestive disorders. If mastication is not properly performed from various causes, it follows that the food in herbivora will not be in a fit state for digestion in the stomach. 2. Loss of Taste. — This occurs in fever and catarrhal affections, and is often associated with loss of the sense of smell, a matter of great importance in our patients, Digitized by Microsoft® 60 VETERINARY THERAPEUTICS ■which depend so much on the smell of food, the result being interference with appetite. 3. Disorders of the Secretions of the Mouth. — In acute febrile diseases we have deficiency of saliva and dryness of the mouth and fauces ; also in long-standing cases of indigestion. This condition also occurs when large doses of such drugs as opium and belladonna have been admin- istered. Salivation consists in an excessive secretion of saliva. It depends on many causes, and is also termed ptyalism. It arises from irregularities or diseases of the teeth, the action of irritating food on the mouth and tongue, and also from disease of the nervous centres, and in affections of the pharynx ; also from the presence of a foreign body in the oesophagus, and occurs as the result of the admin- istration of certain drugs, such as mercury, to the effects of which the cow and dog are particularly susceptible. If given in too large doses, iodine has a similar effect. 4. Derangements of the Excretions of the Mouth. — In the dog we find an offensive smell from the mouth in cases of digestive derangements ; also from accumulations of tartar round the base of the teeth, from diseased teeth, and in some respiratory affections. Glossitis, or inflammation of the tongue, arises from injuries and from chemical irritants, or the administration of medical agents not sufficiently diluted, such as spts. ammon. aromat., ol. tereb., potash, and soda. IV. Natural Recovery. The sense of taste returns when the febrile affection subsides. Salivation ceases after the removal of the cause, and the offensive odour from the breath also disappears if the cause is removed. Digitized by Microsoft® SIALAGOGUES AND AROMATIC BITTERS 61 V. Therapeutics. We will now consider the rational treatment of diseases originating in the mouth. 1. Attention to the Food. — The precaution of avoiding food of an irritating nature, the mode of ensuring proper mastication of the food, and the preparation of the food according to the requirements of the case. 2. Disorders of the Sensory Apparatus of the Mouth. — The deficiency of saliva in fevers, etc. , must be treated by dilute mineral acids, and the acid tartrate of potash, which have the effect of removing thirst. In chronic indigestion, with dryness of the mouth, we prescribe aromatic bitters, and in loss of appetite we rouse the nerves of taste by aromatic bitters with alcohol. 3. Unpleasant Excretions from the Mouth will be treated by ascertaining the cause and acting on it. Glossitis will be treated by the use of astringent gargles, such as borax and water and solutions of potass, chlor., with honey, etc., and demulcents. In cases where it results from the action of irritating medicinal agents not sulEciently diluted, such as preparations of ammonia, it will be found that weak solutions of vinegar with honey will have a beneficial effect. 4. Defects of the Mechanical Apparatus of the Teeth will require special attention and surgical interference. 5. Salivation must be treated according to the cause. If due to the action of drugs their employment must be ceased and belladonna administered. In concluding our consideration of the mouth and contiguous parts, we have to draw attention to an imaginary disease of the palatine bars of the mouth, termed lampas. This, in reality, is due to a temporary congestion of the parts in young horses during the process Digitized by Microsoft® 62 VETERINARY THERAPEUTICS of dentition ; and in adult horses the parts are swollen in cases of indigestion. Obviously, the rational treatment will depend on acting on the cause ; but the most abominable cruelties are often perpetrated in such cases by farriers, who, with a red-hot iron, endeavour to burn away the swollen membrane. It hardly seems credible that any owners of horses will permit such barbarity in the present enlightened age, but we have to confess from experience that some persons, otherwise intelligent, believe the ignorant ideas of grooms and farriers on this subject. CHAPTEE III. DIGESTION— THE STOMACH. I. Physiological Relations. In commencing this brief description, we must draw attention to the fact that substances which stimulate the nerves of taste produce in a reflex manner activity of the gastric functions, and that proper insalivation with the alkaline secretion of the mouth renders the food in a proper state for gastric digestion by increasing the flow of the gastric juice. An important law must be noticed, viz., that acid sub- stances stimulate alkaline secretions, and alkalies stimulate acid secretions. In the diiferent species of patients we find that the stomach varies in arrangement, and that this variation has a very important bearing in pharmacology and therapeutics. Digitized by Microsoft® DIGESTION- THE STOMA CH 63 In the horse the stomach is small in comparison to the size of the animal and to the volume of the intestines. Por various reasons, the occurrence of vomition, except under certain grave conditions of disease, is impossible. This organ is rarely empty, although it has been proved that shortly after food enters it commences to pass on to the intestine. The food entering the empty stomach passes on to the pylorus. As more food is taken, the same process goes on, but the amount passing out does not equal that coming in. When the feed is finished, this passage of ingesta into the duodenum ceases, or only small quantities will pass out, and a long time elapses before the stomach is really empty. The best condition of the organ for the function of digestion is when it is two-thirds full. Other important points in connection with the stomach of the horse are that only a portion of the mucous mem- brane is capable of secreting a digestive fluid, viz., the villous portion. Also the cardiac and pyloric orifices are situated close together, and the cardiac orifice is contracted except when food is entering. The difference in appearance between the cuticular and villous mucous membrane, and the situation of the organ, which rests on the colon, and is not in contact with the abdominal walls, are other points worthy of note. In ruminants the stomach is divided into four com- partments, of which the first three may be considered as dilatations of the oesophagus. It is only in the fourth division that true gastric changes occur. The stomach of the pig is a type between the car- nivorous and ruminant — all portions of it do not possess Digitized by Microsoft® 64 VETERINARY THERAPEUTICS the same powers of digestion. There are two acids formed in gastric digestion in the pig ; for the first hour or two of digestion the acid is lactic, and afterwards hydrochloric acid. The stomach of this animal empties itself very slowly when no fresh food is given. The stomach of the dog is large, and coated through- out with a mucous membrane secreting gastric juice. We may study the functions of the stomach from three standpoints : 1. The secretion of gastric juice. 2. The movements in the organ for the mixing of foods and their passage on to the intestines. 3. Absorption. 1. The gastric juice is an acid secretion, which is derived from the gastric glands. The acidity of this secretion in the horse has been proved to be due to the presence of lactic acid, while in other animals the acid believed to be present is hydrochloric. The digestive ferment is termed pepsin, which has the power of con- verting proteids into peptones. The gastric juice is stimulated to flow by the following agencies : (a) the mechanical presence of food ; (6) by the products of digestion ; (c) by impressions on the nervous centres, such as tastes, etc. ; (d) by the presence of the saliva and any dilute alkaline fluids at the mouths of the gastric tubules. 2. As digestion proceeds, the gastric vessels dilate, there is movement of the muscles of the gastric walls, complex changes occur in the food, and what we term the chyme is formed. 3. As the result of digestive changes, we find that in the stomach about 40 to 50 per cent, of the carbo- hydrates of the food have been converted into sugar, and Digitized by Microsoft® DIGESTION— THE STOMACH 65 40 to 70 per cent, of the proteids have been converted into peptones ; this renders the food fit for absorption. In the horse it has been proved by experiment that httle or no absorption takes place from the stomach, so that the chief process of absorption must occur in the intestines. In the ruminant, the greater portion of the food is acted on in the divisions of the stomach, so that the intestines occupy a minor position in the rdle of digestion in these animals. The Nervous Mechanism of the Stomach. — Of the nerves which govern the secretion of the gastric juice, nothing is yet definitely known. We know that the contact of food, the products of digestion, and dilute alkalies, increase the secretion of the gastric juice. Also that the stomach possesses nervous ganglia in its walls independent of its outside nervous supply, and that the movements of the stomach- wall are excited by the presence of food and stimulation of the vagus nerve. The stomach is supplied by two sets of nerves, and a centre in the medulla — the pneumogastrics, probably the afferent nerves, and the splanchnics the efferent. If the pneumogastrics be stimulated, powerful contraction of the walls of the stomach occurs ; while if the splanch- nics be stimulated, the movements will cease ; we there- fore term the pneumogastrics augmentor nerves and the splanchnics inhibitory nerves to the stomach- wall. Impressions reaching the cerebrum and centre in the medulla are reflected as impulses to the stomach. Impressions from other organs, such as the intestines, liver, kidneys, and all impressionable parts, have also a decided effect on the different functions of the stomach. A point of interest in connection with the nerve-supply of the stomach of ruminants is that the nerves of the third compartment are distinct from those of the re- 5 Digitized by Microsoft® 66 VETERINARY THERAPEUTICS mainder, as stimulation of the pneumogastrics has no effect on the omasum, while it produces contraction of the other three divisions. II. Pharmaco-dynamics. We may now inquire as to the power we have of acting physiologically on the stomach. With regard to horses and ruminants we must admit that from physiological peculiarities our power of inter- ference is far less than in the case of dogs, so that in our consideration of the following points we shall have to draw attention to any important differences which may exist in this respect. 1. Food. — We have great powers of control over the quantity and quality of the food of animals. We can order special diet for certain cases, and pay attention to the periods of feeding. We can regulate the supply of water, and make sure that it is allowed at a proper time as regards the time of feeding. We can use measures to ensure the proper mastication and insalivation of the food. 2. The Power of Interference with the Gastric Juice — • (a) Alkaline stomachics increase the flow of the gastric juice. They consist of dilute alkaline solutions, such as sodii bicarb., etc., administered before feeding. The increase of the salivary flow will also increase the amount of gastric juice secreted. (6) Digestive Adjuvants. — If the constituents of the gastric juice are deficient, we may administer dilute hydrochloric acid or pepsin, or both combined, either along with the food or immediately after feeding. 3. The Power over the Nerves of the Stomach — (a) Stimu- lants to the Nerves of the Stomach. — These increase the sensibility of the nerves, and cause increase of not only Digitized by Microsoft® STOMACHICS 67 the local but also the general circulation ; they increase the activity of the glands, dilate the vessels, and produce a feeling of hunger. These include aromatic bitters, such as gentian, simple bitters, such as calumba, and spirituous preparations of the same. (6) Gastric sedatives reduce the sensibility of the gastric nerves; sensation and the reflection of impressions is lessened. These include opium and belladonna, bismuth, and dilute hydrocyanic acid. There are certain drugs also acting as gastric sedatives which have the power of arresting disorder of the mucous membrane, such as creasote, creolin, and carbolic acid. These are termed gastric disinfectants. (c) We can act on the gastric nerves reflexly by appli- cations to the epigastrium, such as fomentations, poultices, counter-irritants. 4. The Power over the Gastric Circulation — (a) Stimu- lants of the Gastric Circulation. — Those agents which are stimulants to the nerves, dilate the vessels, and increase the blood supply, such as aromatics, bitters, and alcohol, etc. (&) Gastric astringents render the local gastric circula- tion less active. They are indirectly gastric sedatives. Examples. — Dilute acids, opium, salts of zinc, lead, tannic acid, and substances containing it. 5. The Power over the Movements of the Stomach — (a) Gastric or Stomachic Tonics. — Under this head we have such agents as dilute hydrochloric acid and dilute nitric and nitrohydrochloric acid. These, by increasing the acidity of the chyme, increase the uaovements of the stomach. We have also to include specific nervo-mus- cular stimulants, such as nux vomica and its active prin- Digitized by Microsoft® 68 VETERTNARY THERAPEUTICS ciple, strychnine. These have a special action in impart- ing tone to the walls of the stomach, and increasing its movements. {V) Substances lohich diminish the Movements of the Stomach. — These include gastric sedatives, such as opium and dilute hydrocyanic acid ; also alkalies, given after meals, which reduce the acidity of the contents. 6. The Power of Interference with the Contents of the Stomach — (a) Antacids. — These are substances which neutralize the contents of the stomach, such as alkalies. (b) Gastric Disinfectants. — These have the effect of correcting the process of decomposition in the contents of the stomach, and preventing the formation of gas, and include carbolic acid, creasote, creolin, aromatic oils, etc. (c) We may also note the use of antidotes in cases of poisoning as coming under this head. 7. Carminatives. — These are substances which stimulate the gastric nerves, increase the gastric circulation, excite the muscular contractions, and probably relax the cardiac oriiice of the stomach in dogs. They possess more than a local effect, as previously remarked; general stimula- tion also occurs ; thus they are one form of diffusible stimulants. Examples. — Aromatic and pungent oils, alcohol, ether, etc. III. Pathological Relations. The chief cause of disorders of the stomach in all animals may be attributed to errors of feeding. In the horse the stomach is by no means so subject to disease as in ruminants and dogs, because in this animal the intestines have the most important part of digestion to perform, consequently we find that the latter organs are more liable to be affected by disease. Digitized by Microsoft® DYSPEPSIA 69 The reverse holds good in ruminants. As we have ah-eady mentioned, the large and complicated stomach performs the major part of digestion, hence it is more prone to disorders, -while the intestines are rarely affected in comparison. In the dog, although derangements of the stomach are frequent, still, in consequence of the ready power of vomition possessed by this animal, many serious affections are avoided. In the horse affections of the stomach are very serious; thus, in engorgement, as emetics have no effect in this animal, and as food improperly prepared is retained by the action of the pyloric structures, very fatal termina- tions are apt to ensue, especially so when we consider the small size of the organ in comparison with the bulk of food usually taken. Dyspepsia, or derangement of the gastric digestion, is in ruminants and dogs an affection of very common occurrence. We have also to consider that although in horses the effects of this disorder may not be attributed directly to the stomach, still, it has an important bearing on in- testinal affections in an indirect manner by reason of the alimentary matter leaving the stomach before the neces- sary changes have been produced in. it, so as to fit it for intestinal digestion. There are many ways in which derangement of gastric digestion may be brought about, and for all practical purposes we may briefly refer to the following condi- tions as those most commonly met with in all animals : (a) Acute indigestion, with engorgement of the stomach. (6) Indigestion without engorgement — chronic in- digestion, (c) Gastritis — acute and chronic. Digitized by Microsoft® 70 VETERINARY THERAPEUTICS 1. For all these different conditions we can assign many- causes, but to the food must be attributed first place in causation, especially as regards the conditions (a) and (6). Thus, in the horse indigestion with engorgement is generally due to ingestion of food too abundant in quantity, and quickly swallowed without proper mastication and insalivation. The action of cooked foods must be particularly noticed. These when given in large quantities, and especially when the horse is hungry and fatigued, are not properly masticated and acted on by the saliva, the result being that they are rapidly swallowed, and being unfitted to be acted on by the stomach, are retained in it, causing distension of the walls of this organ, the formation of gases, paralysis of the walls, and may even terminate in rupture of the latter. Such foods have the character of bulk and indigesti- bility and liabihty to undergo fermentation in the stomach, although they may not of necessity be in- nutritious. In cattle we have the conditions of distension of the rumen with solid matters, termed plenalvia, and also distension of that organ with gases, derived from fer- mentation of the food, termed hoven, the latter generally due to the ingestion of fresh green food when the animal is not accustomed to such, and the former depending on the introduction of sohd matters in such amount as to paralyze the organ by over -distension, such as grain, food, chaff, potatoes, etc. In the dog engorgement of the stomach is generally reheved by spontaneous vomition, or by the animal naturally eating a certain grass of an einetic nature; consequently we see those conditions noted under headings (5) and (c) oftener than actual engorgement. As regards conditions other than the Digitized by Microsoft® CAUSES OF GASTRIC DISORDERS 71 quantity and quality of the food as causes of gastric in- digestion, we may note the following : 2. Irregularities and diseased conditions connected with the teeth. 3. Deficiency of gastric juice in relation to the amount of the food taken ; also diminution of the gastric secretion after cases of severe illness. 4. Deficiency of the acid of digestion, or of the pepsin ferment. 5. Disorder of the muscular functions of the stomach. In one case we may have feebleness of the movements, from which cause the contents are not exposed in a proper manner to the gastric secretion ; there is also feebleness of the expulsive efforts, and the chyme is kept too long in the stomach, digestion being thus retarded. We may have in another case excess of the peristaltic movements, which has the effect of causing the food to enter the duodenum before gastric digestion is com- pleted. A similar effect will occur if water be given to horses immediately after feeding, the food being washed out of the stomach, and causing intestinal derangement. 6. In young animals we find indigestion occurring from removal from the dam at too early an age, and allowing the young animal to suckle at irregular intervals, such as when the dam is working daily. In such in- stances diarrhoea is usually the chief symptom present. 7. The occurrence of excessive acidity, termed pyrosis, manifested by the animal having a tendency to lick walls, eat clay, etc. 8. Arising from nervous origin. These are due to impressions originating in the intes- tines, liver, kidneys, etc. 9. Organic diseases of the stomach. 10. The actions of certain drugs, such as opium, Digitized by Microsoft® 72 VETERINARY THERAPEUTICS arsenic, digitalis, etc., administered for medicinal pur- poses. If from any of the causes enumerated gastric digestion be not properly performed — in the case of a heavy feed the constituents are only partially acted on — acid decom- position ensues with the formation of organic acids, and we have instead of normal chyme a fermenting mass, resulting in excessive formation of gas. The heart and neighbouring organs become impeded in their action, the nerves, vessels, and glands of the stomach become irritated, the mucous membrane swollen and of a pallid hue, and the surface is covered with a tenacious mucus. The nervous centres are irritated, causing vomiting and eructations of gas in the dog. In the case of the horse, if no relief be given, very serious and fatal results may ensue, either in the occur- rence of cerebral complications or rupture of the organ. If not severe, the contents may pass on to the intestines, causing derangement of the latter by irritation and by reason of excessive acidity. After the acute symptoms have passed off, the morbid state of the mucous membrane may continue with ex- cessive secretion of mucus and arrest of digestive power. There may be pain and loss of appetite, all of which will require appropriate treatment. (6) Indigestion loithout Engorgement — Chronic Indiges- tion. — In this form the attacks are less severe, but may be almost continuous. It may occur from any of the causes mentioned, and must be looked upon as a very troublesome disorder in all animals, and, as we shall see further on, a species of chronic gastritis or gastric catarrh is sometimes responsible for chronic indigestion, especially in dogs. Prom whatever cause the disorder proceeds, in all Digitized by Microsoft® GASTRITIS 73 animals the result is perverted or defective secretion of the gastric glands, evidenced in the horse by capricious appetite, a habit of licking the walls of his stall, and eat- ing clay, foul matters, etc., with acid eructations, thirst, and a sour condition of the mouth. In cattle, chronic indigestion may depend on irregular feeding, bad quality of food, etc., and the presence of parasites, and we may draw attention to a condition of the rumen, in which, either due to a want of tone in its walls, or from the presence of a foreign body in the reticulum, there are frequent attacks of tympanites or hoven. In the dog, as causes of chronic indigestion in addition to dietetic influences, we may include the presence of parasites and foreign bodies in the stomach. (c) Gastritis — Acute and Chronic. — Gastritis, or inflam- mation of the mucous membrane of the stomach, may be considered as either acute or chronic, and also a condi- tion termed gastric catarrh. Acute gastritis, except as the result of the action of irritant poisons, is not so frequent an occurrence in the horse as in other animals. Chronic gastritis may occur from continued errors of dieting, leading to serious altera- tions in the structure and functions of the stomach. It may also depend on organic disease of the organ, or on disease of the liver, in which there is interference with the portal circulation. In cattle gastritis occurs in that affection termed fardel bound, which, although considered by many as due to impaction of the omasum, is in the majority of instances inflammation of the abomasum, or true digestive division of the stomach. We also find gastritis in cattle due to the presence of parasites in the abomasum, especially in young stock, which has often caused serious- losses. Digitized by Microsoft® 74 VETERINARY TEERAPEVTICS Also we find gastritis in cattle due to the action of irritant poisons. In the dog acute gastritis, affecting the muscular and mucous coats, is seldom seen except as the result of irri- tant poisoning. We have, however, to notice a very serious disorder of this animal, termed gastric catarrh, consisting of conges- tion or subacute inflammation of the mucous membrane, with great irritability of the organ, so that it will neither retain food nor medicines. It may arise from the long- continued use of indigestible foods, or the presence of parasites or of foreign bodies in the stomach. It has a tendency to extend to the intestines, causing a very fatal condition. IV. Natural Recovery. In cases of indigestion with engorgement in the dog, the occurrence of vomition affords relief, but the after- effects require therapeutical interference. In horses and cattle prompt and effectual means are required both to remove the cause and to treat the effects which remain. In organic diseases of the organ, treatment can only be palliative. V. Therapeutics. 1. Prophylactic Treatment — (a) Dieting. — This comes ■ first in order, and is one of the most important details not only in the prevention of the various conditions which we have mentioned, but also in their treatment. {b) By artificial means, such as the administration of hydrochloric acid or pepsin, either with or after feeding, in cases where these are deficient. (c) By increasing the gastric secretion in cases where this is not secreted in sufficient amount, such as by the Digitized by Microsoft® TREA TMENT OF GASTRIC AFFECTIONS 75 administration of aromatic bitters, with alcohol and an alkaline stomachic. For example, tincture of gentian •with bicarbonate of soda given before feeding. This is an imitation of the natural insalivation of the food. 2. Immediate Treatment. — When acute indigestion with engorgement exists, the indications are to evacuate the stomach of its contents, to relieve pain, if it be present, to neutralize the excessive acidity, and to expel or absorb the gas which may be formed. In the horse we find that to restore the functional power to the stomach it is necessary to act on the whole alimentary canal by means of a purgative, which has the effect of removing the excess of food from this organ. If combined with the excessive formation of gas, the administration of oil of turpentine in a purgative dose of linseed-oil will be of service, while if pain be present we prescribe in addition a few doses of sulphuric ether. If this pain is not relieved, it will be necessary to employ the hypodermic injection of morphine. The addition of an alkali, to render the contents less acid and more fitted for their passage into the intestines, will be indicated,, such as the bicarbonate of soda with spts. ammon. aromat., and an aromatic bitter, such as gentian. We must remember the extreme danger of engorgement of the stomach in the horse, both as re- gards cerebral complications and rupture of the organ, so that prompt treatment will be required. In cattle the rumen and omasum are the divisions of the stomach which become affected by engorgement and loss of functional activity, the abomasum being the divi- sion liable to chronic indigestion or to gastritis. In these animals all our efforts must be directed to expel the con- tents from the divisions impacted by means of saline and Digitized by Microsoft® 76 VETERINARY THERAPEUTICS oleaginous purgatives, and to encourage a return to the normal state of activity by the means already stated. In the dog, if the impaction of the stomach be not relieved by spontaneous vomition, it will be necessary to administer an emetic. 3. Treatment of the Effects. — If much irritability of the stomach remains, gastric sedatives will be indicated. The organ will require rest, so tliat only small amounts of easily-digested food should be allowed ; if there be much prostration of strength, moderate doses of stimu- lants will be useful. Small doses of bicarbonate of soda and tr. gentian co., administered before feeding, will help to restore the normal secretion of the gastric juice, and neutralize excess of alkaline mucus which may be present. 4. Chronic indigestion is to be treated by carefully ascertaining the cause, and by strict attention to feeding and to the times of feeding. The flow of the gastric secre- tion may require stimulation, but this must not be over- done. The acid of the gastric secretion or the pepsin may be deficient, and will require the administration of digestive adjuvants after feeding. The nervo-muscular structures may require strengthen- ing, such as by the administration of nervo-muscular stimulants and tonics, such as nux vomica and quinine. If there is a tendency to excessive fermentation in the contents, gastric disinfectants will be indicated. If there be a condition of chronic catarrh of the mucous mem- brane, gastric astringents will be required, such as kino, catechu, and substances containing tannin. 5. Gastritis is to be treated by securing as much rest and quietude for the stomach as possible, gastric seda- tives being employed, and demulcents. Digitized by Microsoft® VOMITION AND EMETICS 77 In the dog the stomach becomes very irritable in this affection, persistent vomition being present, so that neither food nor medicine can be retained. Dilute hydro- cyanic acid (gtt. i. to gtt. iii.) with bismuth, and alkahne carbonates, will be found useful in allaying the gastric irritation, and the food must be of a bland, mucilaginous nature. Externally poultices and fomentations to the abdomen should be adopted. 6. In organic diseases of the stomach our treatment can only be palliative. The different symptoms presented will require therapeutical measures on the lines already laid down. CHAPTEE IV. ON VOMITION AND THE ACTIONS AND USES OF EMETICS. I. Physiological Relations. Foe various physiological reasons, the act of vomition does not occur in the horse except under very grave pathological conditions. In ruminants we find the act very rare, and although it would appear that the physiological arrangement would tend to render the act easily performed, we find the re- verse to be the case, so that it is reasonable to conclude that in these animals the vomiting centre is either very rudimentary or not sensible to ordinary impressions. In the dog the act of vomition is very easily induced, both as an effort of nature to relieve the stomach from the presence of irritating or indigestible food, and also by the action of emetics. In the act of vomition there are contractions of the Digitized by Microsoft® 78 VETERINARY THERAPEUTICS longitudinal fibres of the CESophagus, which dilate the cardiac orifice ; the abdominal muscles and the diaphragm contract, and compress the stomach, while the pyloric orifice is closed. The act is a reflex one, depending on afferent nerves from the fauces, stomach, abdominal viscera, peritoneum, etc. ; a centre in the medulla, situated close to the res- piratory centre ; and efferent nerves, the phrenic and nerves to the abdominal muscles. Vomiting may be produced by impressions from distant areas, and also by direct irritation of the nervous centres, such as the presence of certain substances, as apomorphia, in the blood flowing through them. In the act of vomi- tion there are certain associated conditions which occur, besides the evacuation of the contents of the stomach. Thus, a flow of saliva generally precedes the act. The gall-bladder may be forcibly emptied of bile, which may enter the stomach and become expelled. The res- piratory centre is stimulated, expiratory movements occur, the chest is compressed, the respiratory passages are cleared. Perspiration is excited, and 'the cardiac and vascular centres are depressed. II. Pharmaco-dynamics. Emetics are those substances which produce vomiting when administered. Emetics are of two kinds : 1, direct emetics ; 2, indirect emetics. Direct emetics are those which, given by the mouth, cause emesis by local irritation of the nerves of the stomach. Examples. — Sulphate of zinc, sulphate of copper, and the popular emetics, such as salt and warm water, mustard and water, etc. Digitized by Microsoft® VOMITION AND THE USES OF EMETICS 79 Indirect emetics cause emesis by whatever channel they enter the body ; on reaching the blood, they act on the vomiting centre in the medulla, and cause far greater depression than the direct emetics, and also depress the other centres in the medulla. Examples. — Apomorphine, which is the quickest emetic known, and can be administered hypodermically ; anti- mony, and ipecacuanha. The last two act both as direct and indirect emetics. Anti-emetics avert or arrest emesis : 1. Substances which reduce the irritability of the vomiting centre, such as amyl nitrite, chloral, opium, bromides. 2. Sedatives to the afferent nerves of the stomach, such as bismuth, dilute hydrocyanic acid, dilute alkalies, such as limewater, water given as hot as it can be borne, and ice. 3. Measures acting indirectly, such as poultices, fomen- tations and blisters to the epigastrium. III. Pathological Relations. We have two conditions to consider : 1, excessive vomiting ; 2, defective vomiting. Excessive vomiting may occur in affections of the stomach, of the brain, and of other organs. It may also occur from irritation of the vomiting centre, such as from the action of retained urea in the blood, or from the effects of certain poisons. Defective vomiting, with attempts at retching, occurs sometimes from either direct or indirect stimulation of the centre. In cases of poisoning by narcotics, no natural attempt at vomiting occurs, and emetics maybe urgently required to get rid of the poison. Digitized by Microsoft® 80 VETERINARY THERAPEUTICS IV. Natural Recovery. Vomiting may cease after the cause has been removed ; but in some cases it may persist, calhng for interference. If allowed to continue, the irritability of the gastric mucous membrane becomes increased, also the sensibility of the vomiting centre, and great weakness and prostration of strength, due to want of nourishment, is apt to ensue. V. Therapeutics. 1. Excessive Vomiting. — The first indication in the treat- ment of excessive vomiting is to ascertain the cause, and if possible remove it. In the dog, if due to the presence of irritating food, the administration of an emetic will help to remove it ; while if the vomiting occurs in the second stage of indigestion, with irritation of the gastric mucous membrane, gastric sedatives will be indicated. If due to the presence of a poison, then suitable antidotes will be given. If the vomiting be due to some injury or disease of the brain, nervous sedatives, such as bromides of potassium or ammonium, will be useful. If we ascertain the cause to be the presence of some intrinsic poison, such as urea in the blood, which irritates the vomiting centre, we must endeavour to remove it by increasing the action of the bowels, kidneys, and skin. If we fail to ascertain the cause, we must endeavour to reduce the irritability of the gastric nerves and the centre by the administration of such agents as opium, dilute hydrocyanic acid, etc. 2. Defective Vomiting — the Use of Emetics. — For ob- vious reasons, the consideration of the above will only apply to animals which have the power of vomition, as the dog and pig, because horses and ruminants do not respond to the action of emetics. In cases where the presence of indigestible food is not removed by spon- Digitized by Microsoft® VOMIT ION AND THE USES OF EMETICS 81 taneous vomition, also in cases of foreign bodies in the cervical portion of the oesophagus, and inaflfections in which the respiratory passages are blocked, the use of emetics is indicated. In the latter instance, however, great judgment is necessary in order to avoid depressing the patient. Sulphate of zinc, in doses from 10 to 20 grains in 2 ounces of warm water, forms an effectual emetic for the dog. The quickest emetic in cases of poisoning is apo- morphia in a dose of Jj- grain to J^ grain hypodermically. In cases where emetics are indicated in respiratory affections, the use of the vini ipecacuanha, or carbonate of ammonia, is recommended. In instances where drugs are not at our command, we may administer a tablespoonful of mustard in a cup of hot water as an emetic. As contra-indications to the employment of emetics, we may mention the period of gestation, irritation of the gastric mucous membrane, and in cases of debilitating affections. CHAPTER V. DIGESTION— THE INTESTINES. I. Physiological Relations. In the horse the intestines are of large size and capacity, and represent a large extent of mucous membrane. In the ruminants, as previously remarked, the major portion of digestion is carried on by the vast and complex stomach. In the dog the intestines are short and small ; while in omnivora, represented by the pig, the intestines, as regards size, occupy a mean between the carnivora and herbivora. 6 Digitized by Microsoft® 82 VETERINARY THERAPEUTICS When the chyme enters the small intestines, it meets three digestive fluids, viz., the bile, coming from the liver ; the pancreatic juice, from the pancreas ; and the succus entericus, from the glands of the small intestines. As a result of the complex chemical changes which occur, the chyme becomes changed as follovys : it changes its physical character, and becomes alkaline in reaction, and in a fit state for absorption by the lacteals and vessels of the intestines. In connection with the intestines we have to consider : 1. Absorption; 2. Excretion; 3. Peristaltic, action, or transit ; 4. Evacuation. 1. Absorption. — As the chyme passes along the small intestine, certain portions of it become absorbed by the lacteal and portal systems ; it is then carried on to the large intestine, where a further absorption takes place, the remainder forming the faeces. An important point to notice is that a certain amount of fluid passes from the intestine to the blood, and from the blood to the intestine. If absorption be slow there will be more fluid directed into the intestine from the blood, and more rapid trans- mission of the contents, and, as a consequence, the faeces will assume a liquid character. On the other hand, if the absorption be active, there will be less fluid poured out, the transit will be slower, and the faeces will be of a firm character. We can only explain the absorption of water and salts by the portal system on the principles of diffusion, or osmosis. This process will depend on the amount of water, salts, and proteids in the bowel as compared with those in the blood, and also on the nature of these salts and the activity of the circulation through the veins. 2. Excretion. — In the small intestine there is a large Digitized by Microsoft® DIGESTION— THE INTESTINES 83 amount of watery excretion, which is greater than the amount absorbed, consequently the contents are fluid. This excretion is accomplished by the process of osmosis from the vessels, and also by the glands of the intestine being acted on by nervous influence. 3. The Transit of the Contents. — This is accomplished by means of peristaltic action. Peristaltic action is governed by the action of certain nerves, the vagus, when irritated, increasing peristaltic action, and the splanchnics inhibiting it. The intestines also contain local ganglia, which are capable of sustaining the action of the bowel indepen- dently of outside nerve-supply. The ordinary stimuli consist of the presence of ingesta, and probably of a certain proportion of gases in the intestine ; also by the presence of the bile, which in- creases peristalsis. The intestinal movements are also either increased or diminished by the action of different medicinal agents. 4. The General Effects of Evacuation of the Bowels. — The effect is more than a local one, as the whole system is influenced, especially in active purgation. The follow- ing are among the principal effects : (1) A certain amount of water is removed from the blood. This is especially the case with some purga- tives. (2) The bile is cleared out from the small intestine, and the liver thus indirectly stimulated. (3) Deleterious substances are removed from the system, also irritating ingesta and parasites from the intestines. (4) The circulation in the abdomen is modified, the pressure is lessened in the bloodvessels, and the blood flows more freely in the portal system. The circulation Digitized by Microsoft® 84 VETERINARY THERAPEUTICS in the liver is rendered more free and the volume of blood reduced, the cerebral circulation is depressed, the circulation in the kidneys is increased, and diuresis is more readily induced. II. Phannaco-dynamics. We can modify the action of the intestines in various ways, either by attention to the food, by increasing peristaltic action, by increasing the intestinal secretion, or by modifying absorption and excretion. 1. Food. — We must pay attention to the fact that per- fect digestion in the stomach is one of the most important factors in promoting intestinal digestion and preserving a proper action of the intestines. If the food enters the intestine before it is properly acted on by the gastric secretion, it will cause irritation of the intestinal mucous membrane, setting up either colic or enteritis, or, as an effort of nature to remove it, spontaneous diarrhoea. Certain coarse articles of food, such as bran, have the eifect of increasing the action of the intestines and acting as laxatives, and are largely used for this purpose. 2. Agents which act upon the Intestinal Bloodvessels. — We may divide these into: (a) Drastics ; ih) Astringents ; (c) Constringenis. (a) Drastics. — These are powerful and often dangerous purgatives. They cause dilatation of the intestinal blood- vessels, and a transudation of fluid into the walls and cavity of the intestines. They produce a condition of mild catarrh of the intestinal mucous membrane, and liquid evacuations, and require to be prescribed with great caution. Examples. — Croton-oil, gamboge, elaterium. These purgatives are indicated in cases where imme- Digitized by Microsoft® SA LINE P URGA TIVES 85 diate purgation is necessary, such as in affections of the brain, etc., and croton-oil has the advantage of being capable of administration in patients where there is inability to swallow, being small in bulk, and acting when placed on the tongue. (b) Intestinal Vascular Astringents. — These contract the walls of the intestinal bloodvessels, and reduce the amount of the watery excretion, and thus diminish the liquidity of the fseces. Examples. — Salts of lead, diluted mineral acids, etc. (c) Intestinal Gonstringents. — These have a special action on the tissues supporting the small vessels of the intestinal mucous membrane ; they increase the compact- ness of these tissues, diminish the circulation, and reduce the amount of exudation through the vessel walls. Examples. — Persalts of iron, tannin, and substances containing it, such as catechu, kino, etc. 3. Agents which influence Absorption and Excretion — Saline Purgatives. — These modify the process of osmosis in the intestinal wall, and produce two important effects. First, they increase the flow of fluid from the bloodvessels into the cavity of the intestine. Secondly, they are absorbed with a certain amount of fluid into the blood- vessels and into the general circulation, being again partly excreted into the intestine by the intestinal glands, a certain portion being again absorbed. As a result of these processes, a fluid evacuation of the bowels occurs, the rationale of which is not yet clearly under- stood. According to some authorities, saline purgatives also act by increasing the peristaltic action of the intes- tines. Examples of Saline Purgatives. — Sulphate of magnesia, sulphate of soda. Digitized by Microsoft® 86 VETERINARY THERAPEUTICS These purgatives require to be dissolved in a proper proportion of water in order to produce the desired effects. 4. Agents which influence the Intestinal Glands^ (a) Carthartics and Hydragogue Garthartics. — Mercurials moderately increase the secretions of the intestinal glands, and saline purgatives also act as glandular stimulants. Hydragogue cathartics produce very fluid evacuations, and also probably act on the vessels and nerves. Examples. — Jalap, colocynth, podophyllin, etc. (h) Substances ivhich directly diminish the Intestinal Secretions. — Opium, lead, and lime directly diminish the intestinal secretions. Alkalies and their carbonates in- directly produce a similar effect by interfering with the acidity of the chyme, when given in full doses. 5. Agents which influence the Nervo-Muscular Structures of the Intestines. — As we have already seen, there are many substances which act on the intestines through the muscular coat, the nerves, or a combination of both. Drastics even act in a reflex manner. Thus, croton-oil will cause increased peristalsis of the intestine before it has left the stomach. (a) Nervo-Muscular Intestinal Stimulants. — These are generally known as simple imrgatives, and the mildest of the group are termed aperients or laxatives, such as castor- oil, raw linseed-oil, etc. Simple purgatives act chiefly or entirely on the intestinal muscles, and cause a much less fluid evacuation than that produced by saline or cathartic purgatives, with less action on the portal and general circulation. Examples. — Aloes, rhubarb, etc. They are generally combined with a carminative, to prevent pain from excessive muscular contraction. Digitized by Microsoft® ANTHELMINTICS 87 Certain drugs assist the action of such purgatives, such as nux vomica, belladonna, the latter acting by its power of lessening the inhibition of the splanchnic nerves. (6) Nervo-Musmdar Intestinal Sedatives.— These arrest the movements of the intestine, either directly or by acting on the nerves. Examples.— Oi^ium, morphine, lead, etc. Bismuth, chalk, etc., diminish peristaltic action by forming a protective coating on the mucous membrane, and indirectly by diminishing the acidity and irritability of the contents. All the substances under this heading are astrin- gents. 6. Cholagogues. — These increase peristaltic action of the - intestines by increasing the flow of the bile, which is a natural stimulant of the muscular coat. They are divided into : (a) Direct cholagogues , which stimulate directly the liver-cells and the gall-bladder. Indirect cholagogues, which indirectly stimulate the biliary secretion by clearing out the bile which is present in the intestine, and thus a fresh flow is induced. Examples of Direct Cholagogues. — Podophyllin, sulphate of soda, etc. Examples of Indirect Cholagogues. — Mercurials, such as calomel, pil. hydrargyri, etc. We have also to mention that most purgatives are indirect cholagogues, and that many purgatives are direct cholagogues, while all cholagogues are purgatives. 7. Anthelmintics are medicines which kill or expel parasites from their various locations in the body. They are divided into : 1. Vermifuges, which expel the parasites without of Digitized by Microsoft® 88 VETERINARY THERAPEUTICS necessity destroying them. These belong to the group of cathartic purgatives, and by their action the parasites are removed from the intestine in the excreta. 2. Verviicides destroy the parasites, and it is clear that a combination of both a vermifuge and a vermicide will be advantageous. Certain vermicides have a special action on certain species of parasites. Thus, areca-nut and the extract of male shield fern are useful for acting on the varieties of tapeworm, santonin for round worms. The oxyures, or thread- worms, found in the rectum, are best acted on by anthelmintic enemata, such as decoctions of quassia or aloes. Oil of turpentine is a valuable anthelmintic in horses and cattle, but requires to be used with great caution in dogs. All anthelmintics act better when the stomach and intestines are moderately empty and the contents soft, and in many instances the medicinal agents will require repetition. Small doses of salines and mineral tonics will also be useful to induce a healthy condition of the alimentary canal. The parasites infesting the bronchial tubes of young cattle and lambs are best acted upon by intertracheal injections of solutions specially prepared, generally con- sisting of small amounts of such agents as oil of turpen- tine, carbolic acid, etc. By this method the parasites are directly destroyed and expelled. III. Pathological Relations. Under the above heading we have the following con- ditions to consider, and may remark that in ruminants affections of the intestines are seldom met with in com- parison to their frequency in horses and dogs. Digitized by Microsoft® INTESTINAL AFFECTIONS 89 1. Excessive Intestinal Action — Diarrhoea. 2. Deficient Intestinal Action — Constipation. 3. Impaction of the Large Intestines, luith Paralysis of the Muscular Goat. 4. Spasm of the Intestines, or Colic. 5. Inflammation of the Intestines, or Enteritis. 6. Volvulus and Intussusception. 7. Tympanitis of the Intestines, or Flatulent Colic. 1. Excessive Intestinal Action is often referable to gastric indigestion, and may depend on irregularities in feeding, and the passage of the food into the intestines before it has been properly acted on by the gastric secre- tion. Certain poisons originating in the body itself, such as urea, and the poison of pyaemia, will also cause diarrhoea. It may also occur as the result of an overdose of a purgative, or in cases of individual idiosyncrasies from the action of even a moderate purgative. In young animals, such as foals, diarrhoea is frequently seen from mismanagement, such as overworking the dam, feeding her on improper food, and allowing the young animal to suckle her at irregular intervals, when the stomach of the foal has become weakened by prolonged abstinence, the result being that indigestion occurs. These cases often become serious if unchecked, as a form of catarrh of the mucous membrane of the intestinal canal is apt to ensue. We must regard diarrhoea rather as a symptom than as an actual disease. 2. Deficient Intestinal Action, or Constipation, depends on various causes. It may be due to a want of tone in the muscular coat of the intestines, depending on loss of vigour of the nerves, which do not respond to the natural stimuli. Also to insufficient exercise, and a long con- Digitized by Microsoft® 90 VETERINARY THERAPEUTICS tinuance in dr}- articles of food. Defective biliary secre- tion is also a common cause. We must, regard constipation as but a symptom of some existing condition rather than as a disease. Dogs, especially those kept as pets, with pampered appetites and insufficient exercise, are very subject to deficient action of the intestines, often leading to serious conditions. In foals, shortly after birth, there may be a condition of constipation due to inability to pass off the meconium, which, if not relieved, may lead to grave consequences. 3. Impaction of the Large Intestines. — This may depend on loss of tone in the muscular coat, whereby the intes- tinal contents accumulate and completely arrest the action of the bowels, and block the passage. In the horse the double colon is often the seat of this affection, dry, bulky, indigestible food being a predis- posing cause. Calculi and concretions formed in the intestine also are causes of obstruction, and tumours mechanically interfering vrith the parts are sometimes met with. In the dog, impaction with paralysis of the intestine is an occurrence very frequently met with, and a peculiar symptom sometimes is present in such cases, i.e., the occurrence of paralysis of the hind extremities of the animal. In this animal accumulations of faecal matter may assume a very hard character, causing serious symptoms. We may also refer to the presence of foreign bodies and sharp bones swallowed as causes of intestinal obstruction in the dog. 4. Spasm of the Intestines, or Colic, is an affection of very frequent occurrence in horses. It consists of a spasmodic contraction of the muscular coats of the intes- tine, and is generally referable to irregularities in feeding, Digitized by Microsoft® INTESTINAL AFFECTIONS 91 the processes of mastication, salivation, and gastric digestion not being properly performed from various causes. Irritation is set up in the intestines, leading to the occurrence of the symptoms which we recognise as those of colic. 5. Inflammation of the Intestines, or Enteritis, is one of the most fatal affections to which the horse is liable. It may arise from various causes ; in many instances it is impossible to assign any definite cause, and authorities are not yet agreed as to whether colic if severe and un- checked will terminate in enteritis, or whether the latter affection has a distinct origin and course of its own. Enteritis consists in inflammation of the mucous coat of the intestines, the large being oftener attacked than the small. As the disease progresses, all the coats of the intestines become involved in the inflammatory process. In some cases the disease runs a very rapid course, the postmortem appearances showing extensive extravasa- tion of blood into the cavity of the bowels, resembling a form of apoplexy of these organs rather than an ordinary form of inflammation. 6. Volvulus and Intussusception, and other forms of grave intestinal lesions, are generally hopeless cases, and beyond the aid of the therapeutist. However, we may venture to hope in the near future, when abdominal surgery shall be better understood as applied to animals, that surgical interference may be brought to bear with benefit in such cases. 7. Tympanitis of the Intestine, or Flatulent Colic, is that condition in which there is distension of the bowels by the presence of gas, arising from food which easily undergoes fermentation, the pain not being so acute as in the spasmodic form, but the constitutional disturbance greater. Digitized by Microsoft® 92 VETERINARY THERAPEUTICS Tympanitis may occur during the progress of another disease, where exhaustion is a prominent feature. It also occurs in cases of obstruction of the intestines from calculi, tumours, and other mechanical causes, and must always be regarded as a very grave symptom. IV. Natural Recovery. As previously stated, we often find that diarrhoea is an effort of nature to remove some irritating material from the intestinal canal. When this cause is removed the symptoms may cease, but we shall find that therapeutic measures will be required either to help the removal of the irritant, or to combat excessive symptoms in many cases. In all the other pathological conditions noted, the aid of the therapeutist will be required, as spontaneous recovery is seldom seen. V. Therapeutics. The Uses of Purgatives. — The intestines of the horse present a very extensive surface of mucous membrane, and great care is essential in the administration of purgatives in order to avoid the occurrence of super- purgation. If possible, for two days prior to the administration of a purgative, the animal should be pre- pared by being fed on bran-mashes, so as to render the intestinal contents soft and easily acted on, and thus to avoid any irritating effects as much as possible. By this means a much smaller dose of the purgative will suffice to bring about desired results. Up to the present the drug chiefly employed to produce purgation in the horse is aloes, administered in the form of a properly-prepared bolus. Saline purgatives have an uncertain action in this animal, while the use of laxatives, Digitized by Microsoft® USES OF PURGATIVES 93 such as raw linseed-oil, are indicated in cases where we wish to act on the intestines without danger of any irritating effects. The animal having been properly prepared, if a moderate dose of aloes be administered in the morning, purgation will usually ensue in from ten to twelve hours. The animal should have gentle walking exercise until the physic commences to operate, when he should be placed in his stall, with proper clothing applied, and a liberal supply of warm bran-mashes allowed, care being taken to avoid cold drinks by having the chill taken off the water allowed. In ruminants, in consequence of the development of the stomach and the large amount of ingesta contained therein, the action of purgatives is slow and often uncer- tain, the average time being twelve to sixteen hours. Saline purgatives largely diluted give the best results, while in obstinate cases croton-oil with calomel are to be preferred. Sheep generally take about one-fourth the dose required for cattle. Sulphate of magnesia largely diluted or castor-oil are the safest agents ; drastics such as croton- oil should be avoided. In the dog purgation is easily induced, the alimentary canal being comparatively small and the ingesta not bulky. Either castor-oil, or jalap with calomel, gives the best results, while it is important to remember that the mixture should be prepared in as palatable a form as possible, so as to avoid the tendency to produce vomition. Purgatives generally act in from five to eight hours in this animal, and in obstinate cases should be assisted by the administration of enemas. In the pig either castor-oil or sulphate of magnesia acts well. Digitized by Microsoft® 94 VETERINARY TtlERAPEUTICS We will now consider the therapeutical relations of the following conditions. 1. Deficient Intestinal Action— the Use of Purgatives. 2. Excessive Intestinal Activity— the Use of Astrin- gents, and the Treatment of Diarrhea. 1. Deficient Intestinal Action varies in degree from what is known as ordinary constipation to a condition of great gravity, in which there is total stoppage of the bowels, with perhaps paralysis of the muscular coat of the intestine. In the treatment of ordinary constipation the cause must first be discovered and removed. Attention must be directed to the food, to the digestion, to the amount of exercise, and to the state of the liver. If the condition become chronic, it will generally be found due to a icant of tone, or torpidity of the muscular coat of the intestine, in which nervo-muscular stimulants will be indicated, after free purgation has been induced by the administration of a purgative. Thus, medicinal doses of nux vomica, with small doses of aloes and bella- donna, will be found very useful in such cases, with occa- sional administration of saline cholagogues, such as sulphate of soda. In cases of impaction of the intestines, violent purga- tives should be avoided, the use of oleaginous laxatives being indicated, with the liberal use of purgative enemata, administered by means of a special long tube. In cases of colic, or spasm of the intestines, generally due to the presence of irritating ingesta, an oleaginous purgative should be administered, with an antispasmodic to relieve the pain. Other Uses of Purgatives. — Besides the use of purgatives for the conditions we have mentioned, there are many Digitized by Microsoft® USES OF PURGATIVES 95 other important indications in which they are employed with benefit. (a) For the Beduction of the General Blood Pressure. — In cases of cerebral congestion, of dropsy due to over- loading of the portal system and systemic veins, hydra- gogue cathartics and salines are very useful, relieving the circulation, and removing a large amount of fluid by the intestines. ip) At the commencement of some inflammatory affec- tions, such as lymphangitis, laminitis, irritative fever due to wounds, etc. (c) In cases of inflammation of the liver and kidneys purgatives have a beneficial action, removing by the intestines the excrementitions matters which, by reason of the loss of function of the former organs, remain in the system. {d) For removing from the alimentary canal parasites, and also for relieving the stomach of irritating ingesta, and in cases of engorgement of that organ leading to cerebral complications. Also in cases of diarrhcea due to the presence of irritating material in the intestines, a moderate aperient is the first indication in treat- ment. Contra-indications of Purgatives. — In inflammatory conditions of the intestines, in peritonitis, in volvulus and intussusception, in hernia, etc., purgatives must be studiously avoided, as peristaltic movements increase the diseased condition, and temporary paralysis of the intes- tine must be aimed at. Again, in all cases of a debilitating nature, such as influenza, respiratory affections, etc., purgatives have a depressing and weakening effect, and if their use is abso- lutely required, only the mildest laxatives should be employed, with the use of enemata in addition. Digitized by Microsoft® 96 VETERINARY THERAPEUTICS 2. Excessive Intestinal Activity— the Treatment of Diarrhoea. — The first step in the treatment of diarrhoea is to ascertain the cause, and, if possible, remove it. If due to irrational methods of feeding, these should be imme- diately attended to. Some animals, especially horses, are very subject to an attack of diarrhoea without any appreciable cause, and require careful attention in the way of feeding. Care should be taken that the food is properly acted on in the mouth, and also that gastric digestion is properly performed, and that the animal is watered at a proper time. Unless the diarrhoea is excessive, it will be advisable, in cases where it is due to the presence of irritating ingesta in the intestines, to help the efforts of nature to remove the cause by the administration of an oleaginous laxative. In young animals, where the affection is often due to the milk being deteriorated in quality, and allowed at irregular intervals, a similar course should be adopted at the commencement, bearing in mind, however, the great danger of intestinal catarrh, with weakness of the patient, supervening if the condition is allowed to continue with- out treatment being adopted. If the diarrhoea be due to renal or hepatic disorders, cholagogues with diuretics in moderate doses will be useful. If it be due to excessive acidity of the duodenum, alkalies, such as bicarbonate of soda or chalk, should be administered. If the diarrhoea persists after our efforts to remove the cause, we are compelled to treat the effects, remembering that these should not be allowed to continue too long before treatment is adopted. For this purpose we pre- scribe intestinal constringents with intestinal nervo- muscular sedatives. Substances containing tannic acid, Digitized by Microsoft® TREATMENT OF INTESTINAL AFFECTIONS. 97 such as catechu or kino, with preparations of opium, such as the tincture of opium or chlorodyne, to which may be added a dose of prepared chalk, give excellent results, and may be administered in flour or starch gruel, the former by preference. The drinking water should have the chill removed, and the food should be of as digestible a nature as possible, and the animal kept sufficiently warm. In cases of superpurgation due to the excessive action of cathartics, very careful attention is necessary. Many of such instances will yield to a dose of tincture of opium combined with a carminative, but some cases require the use of stimulants, of which brandy is to be preferred; In cases of dysentery, the intestinal vascular astrin- gents are employed, such as lead combined with opium and dilute sulphuric acid. Treatment of Flatulent Colic. — In this condition our efforts must be directed to neutralize the gas in the intes- tine, to promote action of the bowels, and to relieve the pain. For these purposes the oil of turpentine, with some preparation of ammonia and a large dose of raw linseed-oil, gives satisfactory results, and the action should be assisted by the use of enemata. In very severe cases, with symptoms of great distress, it will be necessary to perform the operation of punctur- ing the distended bowel with a special trocar and cannula, so as to allow the excessive amount of gas to pass off, and thus avert a fatal termination. Treatment of Enteritis. — In this affection, as previously stated, all purgatives should be rigidly withheld, as the chances of recovery, although very slight, will depend on keeping the inflamed part in as complete a state of rest as possible. The skill of the therapeutist should be directed tc 7 Digitized by Microsoft® 98 VETERINARY THERAPEUTICS subduing the excessive pain by the administration of anodynes, of which opium and its alkaloid, morphia, combined with atropia, are those in general use. We have to consider that in this affection very large doses of these drugs will be tolerated, and as in many horses those agents mentioned act as cerebro-spinal excitants, and fail to give relief, it will be necessary to administer a hypnotic, such as chloral hydrate or the drug cannabis indica, which is now coming into favour as a valuable anodyne for the horse. The Treatment of Obstruction of the Intestine due to Impaction or other Causes. — In these cases the use of strong purgatives is also contra-indicated, as likely to cause rupture of the intestinal wall, or enteritis. Oleagin- ous laxatives should be administered and purgative enemata persevered in, the long rectum tube being of vast service in such cases. If we are enabled to diagnose the case to be a paralyzed condition of the colon, with accumulation of the contents, then the use of hypodermic injections of eserine, combined with pilocarpine, is indicated, and has given most satisfactory results, the former of these drugs causing energetic contractions of the muscular coat of the intestines, with increased secretion of the intestinal fluids, the latter causing exces- sive secretion of the intestinal glands. If the obstruction be due to other causes, this treatment will only hasten the fatal result, besides causing excessive pain to the animal. Finally, we may state that in all intestinal disorders, where pain is a prominent symptom, our immediate efforts should be directed to subdue it, as pain, if allowed to continue, will lead to very serious results. If we could always diagnose the cause of abdominal pain correctly, then indeed our efforts should be directed Digitized by Microsoft® TREATMENT OF INTESTINAL AFFECTIONS 99 to remove this cause, and treat the effects which may remain. If we are positive from our observation and judgment of the symptoms that a certain case is one of spasmodic colic, due to the presence of irritating ingesta in the intestines, then the rational treatment would be the administration of a cathartic immediately. But, unfortunately, in all cases the symptoms presented are not sufficiently diagnostic to enable us to do this with certainty, and the primary symptoms of abdominal pain may be the precursor of very serious conditions, where active purgatives would be not only injurious, but would increase the tendency to a fatal result. We have also to take into consideration the length of time which a cathartic dose will take to produce its effects in a horse which is not prepared. Practitioners differ in their opinions with reference to treatment in such cases, some advocating the adminis- tration of an active cathartic on the first symptoms of spasmodic colic being shown, with an antispasmodic to relieve the pain ; others regard the relief of the pain as of primary importance, and at the same time administer an oleaginous aperient, which, in the event of a more serious condition supervening, cannot be productive of any injurious effect. We may add that the latter is the practice recommended by authorities on human medicine. Digitized by Microsoft® 100 VETERINARY THERAPEUTICS CHAPTER VI. ON ENEMATA. Enemata are fluids of various compositions introduced into the rectum for the following therapeutical pur- poses : 1. To procure evacuation of the bowels. 2. To restrain severe diarrhoea. 3. To destroy and remove parasites in this location. 4. By reflex action to procure soothing effects on the pelvic organs. 5. To act as nutrients to the system when feeding by the mouth is impossible or contra-indicated. 1. Enemata for the purpose of procuring evacuation of the bowels may be either simple, consisting of warm water with soap rubbed up therein, or ptirgative, such as injections of castor-oil, raw linseed-oil, or solutions of aloes. In either of these instances we do not intend the action to be merely a local one by removing the contents of the rectum, but to stimulate the whole intestinal tract to increased peristaltic action. In the case of simple enemata, to effect this purpose it is necessary to introduce a large amount of fluid, so that the lower portion of the intestine shall be distended, and the action of the parts beyond this excited. To perform this effectually certain points must be attended to. We must consider that the large colon is that portion of the intestine which is usually affected by impaction, etc., and that this part is out of reach of mechanical interference. Also, we have to consider the great length of the rectum and floating colon of the horse, Digitized by Microsoft® ON ENEMA TA 101 the former being about two feet in length, the latter about ten feet. To simply inJQct fluids into the rectum with an ordinary- syringe and short tube in the hope of acting on impaction located in the large colon must of necessity be a failure, as, after a certain amount has been injected, it will pass out, and simply remove the contents of a portion of the rectum. What our object should be is this : to ensure that the fluid shall find its way as far up the intestine as possible, and remain there for a certain period so as to excite the peristaltic action of the portion of the intestine requiring it. The rectum tube invented and recommended by Pro- fessor Smith, A.V.D., for this purpose is a most useful instrument in cases of impaction of the colon, but certain precautions are necessary in using it. The rectum should first be cleared of all excreta as far up as possible with the hand. The tube, being well smeared with vaseline, is attached to the enema syringe, the best pattern of the latter being that invented by Winton, which is slow and steady in its action. The tube is now carefully intro- duced into the rectum, and the syringe slowly and steadily worked. As the bowel becomes dilated by the fluid the tube can be easily passed along, no force being used at any time. By this means a large amount of fluid can be introduced into that portion of the intestine where its action will be productive of benefit, and where a certain portion will be likely to remain. Of course, in cases of severe abdominal pain it would be a matter of impossibility to use such a tube. In such instances the pain should first be relieved by the adminis- tration of anodynes, either by the mouth or by sub- cutaneous injection. The long tube is only required in eases of impaction of Digitized by Microsoft® 102 VETERINARY THERAPEUTICS the colon, a tube of about half the length sufBcing for ordinary cases. In using purgative enemata, we should be careful to employ only moderate amounts at a time, so as to ensure that they shall be retained for a proper period. Here again we find the long tube of infinite service in cases of impaction, a mixture of castor-oil and raw linseed-oil carefully injected producing most favourable results. In canine practice for similar purposes, the long tube is an essential factor in the treatment of impaction of the colon. In the dog we find in these cases a condition of great irritability of the stomach, so that it is impossible to cause oleaginous remedies to be retained when adminis- tered by the mouth, as vomition quickly occurs. We may also refer to the excellent results obtained by the use of enemata of glycerine in cases of impaction of the bowels, and in dogs the use of suppositories of glycerine often is most satisfactory. In cases of flatulent distension of the bowels we find the use of enemata very beneficial, especially when such are medicated by the addition of such agents as oil of turpentine, asafoetida, etc., care being taken that the former is administered well mixed with some bland substance, so as to avoid its irritating effect on the mucous membrane. 2. Enemata to act as sedatives and astringents to the bowels in cases of severe diarrhoea should be small in bulk, the basis being of boiled starch medicated with tincture of opium, and astringents, such as acetate of lead or substances containing tannin. 3. Enemata to destroy parasites infesting the rectum are medicated with some vermicide, such as quassia, weak solutions of tincture of iron, or solutions of common salt. Digitized by Microsoft® ON ENEMATA ]03 ^. Enemata of warm water produce soothing effects on the intestines and neighbouring organs, and are useful in reducing the pain of cystitis and pelvic and abdominal pain generally. 5. Nutritive enemata are employed in eases where swallowing is difficult or impossible, also in persistent vomiting, and in painful organic diseases of the stomach. Such enemata should be small in amount, and composed of bland, unirritating materials, so as to favour absorp- tion from the intestinal mucous membrane. The nutrient material should be prepared in a form capable of being freely absorbed, such as by the addition of pepsin and dilute hydrochloric acid, or by adding a pancreatic' ferment, such as mixing a portion of the pancreas of an ox or pig with meat, both being reduced to a state of fine division, and rubbed together with warm water. Eggs are capable of being absorbed without the process of peptonization. CHAPTEE VII. THE LIVER. I. Physiological Relations. The liver is the largest gland in the body, and has several important functions to perform, not only con- cerned with the process of digestion, but also with nutrition and excretion. Thus we may note the forma- tion of the bile, the regulation of the supply of sugar to the system, the storing up of glycogen. We have also to remember that the liver is an excretory organ ; thus, Digitized by Microsoft® 104 VETERINARY THERAPEUTICS certain nitrogenous products of digestion are converted into urea and uric acid in this organ, and rendered capable of being excreted from the body. Another point worthy of attention is that there is no gall-bladder in the horse, so that the bile flows into the intestine according as it is prepared in the liver ; in the other animals a gall-bladder is present in which the bile is stored up until it is required. The absence of the gall-bladder in the horse is accounted for by the fact that in this animal food in more or less amount is continually passing along the small intestines, so that the bile is in constant demand, while in other animals, in which the food remains a certain time in the stomach, the bile is only required when the chyme passes on to the duo- denum, and in the interval it is stored in the gall- bladder. The functions of the bile are very important ; briefly they may be stated as follows : The emulsifying and saponifying of fats, and as an auxiliary to the pancreas in its action on starch, the prevention of putre- faction in the intestinal contents, and the promotior^of the peristaltic action in the intestines. The circulation of the bile is of great importance from a therapeutical point of view. The bile which flows into the intestine and mixes with the chyme is not all got rid of by the fasces. The biliary salts become reabsorbed and returned to the liver, from whence they are again secreted and carried to the intestine. II. Pharmacodynamics. We can influence the liver in various ways : 1. Food. — The amount of food allowed will influence the secretion of bile, the amount of urea and the pro- portion of glycogen stored up ; the nature of the food will also have a similar influence. Digitized by Microsoft® THE LIVER 105 2. Exercise will increase the amount of oxygen reach- ing the liver, and thus render more complete the processes carried on therein. 3. The Supply to the Liver can be diminished by hydra- gogue purgatives, which carry away a certain proportion of water from the radicles of the portal vein in the intestinal walls, and remove it from the system. 4. The Products of the Liver can be influenced, and important effects on the organ produced. If bile or urea accumulate in the liver, its functions will be inter- fered with. By means of indirect cholagogues we can clear out the intestines and the bile contained therein, consequently the bile-salts, instead of being absorbed, are removed from the body ; their absence from the portal vein and liver causes the hepatic cells to secrete fresh bile. Mercurials are specially useful in this respect. 5. The Metabolic Processes in the Liver can be modified by Specific Hepatic Stimulants and Depressants. — Bicar- bonate of soda, dilute nitrohydrochloric acid, and arsenic increase the flow of bile and glycogen. Amyl nitrite stimulates the glycogenic function. Direct cholagogues increase the flow of bile. Chloride of ammonium and iron increase the amount of urea. Opium and morphia reduce the whole process of hepatic activity ; quinine and alcohol have a similar action in a less degree. III. Pathological Relations. Disorders of the liver are generally due to the following causes : (a) Errors in feeding; (6) want of sufficient exercise and proper hygienic surroundings ; (c) retention of the products of the organ due to inactivity of the othei- exeretory organs — the kidneys, lungs, or bowels. The different causes inducing derangement of the liver pro- Digitized by Microsoft® 106 VETERINARY THERAPEUTICS duce certain definite phenomena in the organ and in the general system. The chemical processes in the organ are disturbed, the composition of the excretions is altered, and certain symptoms are observed as a consequence of the presence in the blood of certain products. In the disturbance of the natural functions of the liver, whether due to structural changes in the organ or not, there are a few important symptoms which we recognise as generally present : 1. Jaundice — due to some disturbance in the formation and secretion of the bile, or to reabsorption of the bile after it has been secreted. We must, however, draw attention to the fact that in many cases of extensive disease of the liver this symptom may be absent. 2. There may be the exhibition of pain, evidenced by colicky symptoms or uneasiness. 3. Persistent lameness in the off shoulder in horses. 4. In far-advanced oases of liver diseases, with changes in the hepatic structure and obstruction to the portal circulation, we may have the occurrence of intestinal catarrh, and the presence of fluid in the abdominal cavity, termed ascites. 5. In dogs, obstinate and persistent vomiting. As changes in the general system, the result of dis- orders of the liver, we may note disturbance of the nervous system and interference with general nutrition. The urine contains an excess of urea, the colouring matter is increased, and leuoin and tyrosin are present. The bile is altered in quality and quantity, causing either diarrhoea, with pale, foul evacuations, or constipation. The glycogenic function of the liver may be disturbed, giving rise to the presence of sugar in the urine, one of the leading phenomena of that disease termed diabetes mellitus. Digitized by Microsoft® HEP A TIC A FFECTIONS 1 07 We may remark that liver affections are of very frequent occurrence in dogs, less often seen in horses and cattle, and that in many instances they are not diagnosed with facility. The affections usually met with are : 1. Congestion of the Liver. 2. Hepatitis, or Inflammation of the Liver. 3. Chronic Diseases of the Liver. 4. Parasitic Diseases of the Liver. 1. Congestion of the Liver. — The vascular arrangement of the liver renders the condition of excess of blood in its capillary system one which is, comparatively speaking, easily induced. We may divide this condition into : (a) Passive congestion ; (b) active congestion ; (c) biliary congestion. (a) Passive Congestion is the most common form met with. It consists of obstructed blood-flow in the portal and hepatic veins, depending upon a reflux of blood from external organs and surfaces, with disease of certain viscera, such as the heart and lungs. (6) Active Coiigestion depends on an increased or exces- sive supply of blood to the gland, in which the capillaries of the portal vein or hepatic arteries become distended. A slight amount of adtive congestion of the liver accom- panies the process of digestion, while over-feeding on highly stimulating food, without a proper amount of exercise, tends to intensify this condition. (c) Biliary Congestion consists in overloading of the minute bile-ducts with bile, and depends on either or both of the conditions just described. In one case the bile-ducts are pressed upon by the engorged vessels, and the bile is prevented from escaping ; in the other, there is excess of bile secreted from the extra supply of blood, and the ducts are not able to remove it. Digitized by Microsoft® 108 VETElilNARY THERAPEUTICS All these conditions, if frequently occurring, lead to bilious contamination of the blood and to structural changes in the liver, with the usual train of symptoms. 2. Hepatitis, consisting of inflammation of the fibrous covering of the liver, or of inflammation of the component gland structure of the organ, is not often diagnosed, but the results of postmortem examinations show the con- dition to be more common than is usually supposed. 3. Chronic Diseases of the Liver are more commonly met with in dogs than in horses or cattle. The forms usually found are cirrhosis, fatty degeneration, albuminoid or lardaceous liver; also the occurrence of morbid growths, such as carcinomata, sarcomata, and tubercle must be noted. 4. Parasitic Diseases of the Liver are of great import- ance. Among these we may mention the cystic form of the Taenia eohinococcus in the horse, and the presence of the Distoma hepaticum in sheep, causing that affection termed liver-rot. IV. Natural Recovery. In most cases the aid of the therapeutist will be re- qiiired, but the usual nausea produced may cause absti- nence from stimulating food, and thus give the organ rest, while bilious vomiting and bilious diarrhoea in dogs will help to remove the excess of bile. The general depression and constitutional symptoms will require immediate treatment. We must consider that in cases of extensive structural change palliative treatment is the only resort. V. Therapeutics. Preventive treatment will consist in attention to feeding and exercise, and to a proper condition of diges- tion and of the excretory organs. Digitized by Microsoft® TREA TMENT OF HEP A TIC A FFECTIONS 109 The immediate treatment will consist in all classes &f patients in the administration of a cholagogue cathartic to clear out all bile from the intestine. This should be followed up by doses of salines, such as the sulphate of soda or of magnesia. In chronic cases small doses of calomel are indicated, also bicarbonate of soda given after feeding. Dilute nitro- hydrochloric acid, with quinine and stomachics, are useful in bringing about a healthy condition of the organ. In cases where there are severe effects as a result of hepatic disorder, we must direct our efforts to relieve them as well as acting on the organ itself. Thus, obstinate vomiting, which is often present in dogs, must be relieved by gastric sedatives, such as bismuth, dilute hydrocyanic acid, hot fomentations to the abdomen, etc. If there be much debility present stimulants may be required, and even small doses of opium when pain is present ; but these remedies should be avoided as much as possible, as they are likely to cause further hepatic disorder. In cases of congestion of the liver, hydragogue cathar- tics are indicated to relieve the portal circulation. This treatment should be followed up by the administration of salines, such as the sulphates of magnesia and soda, which also act as diuretics, and thus help to afford relief to the liver. In the treatment of diabetes mellitus the feeding is of first importance, saccharine and amyloid substances being avoided as much as possible. As regards the use of drugs in this affection, the best results have been obtained from the administration of opium and its active principles, morphine, morphia and eodeia, such drugs being borne in large doses in such cases. Digitized by Microsoft® 110 VETERINARY THERAPEUTICS OHAPTEE VIII. THE BLOOD. We may regard the blood as a fluid medium bearing important relations to all organs of the body, such relations consisting in conveying nutrient material and oxygen to the tissues, and carrying away the results of tissue activity. There are few primary affections of the blood itself, but morbid changes occur, depending on its source of supply, and also on the organs performing the important functions of excretion, such changes being of special interest to the therapeutist. We have also to notice an important fact, viz., that it is through the blood that the active principles of drugs reach the organs of the body, on which they produce their specific effect, and few drugs act directly on the blood itself. I. Physiological Belations. The liquor sanguinis or plasma, is the medium of nutrition, carrying the various nutritive materials be- tween the different organs of the body, and removing the products of the vital processes, viz., the carbonic acid, water, urea, salts, etc. It has an alkaline reaction, depending on the presence of salts of soda, and varies in composition according to the difi'erent active organs through which it is passing, so we may regard it as having a process of supply, of expenditure, and of excretion. The White Corpuscles are believed to have a special nutritive function. The Ked Corpuscles have the important function of carrying oxygen from the lungs to the tissues, and con- Digitized by Microsoft® THE BLOOD 111 sist chiefly of haemoglobin, of which iron is an important component ; the chief salts are those of potassium, gene- rally in combination with phosphoric acid. II. Pharmaco-dynamics. We can influence the blood in various ways : 1. By Influencing its Supply. — This can be accom- plished by modifying the food, by altering the digestion and the hepatic functions. 2. The Alkalinity of the Plasma can be increased or reduced within certain limits. It is increased by the administration of alkalies and alkaline earths, of which salts of potassium act the quickest, but salts of sodium, although acting slower, have a more permanent effect. Alkalies may also act indirectly by combining with the uric acid, and being removed by the kidneys. It is difficult to reduce the natural alkalinity, as mineral acids administered enter the blood in the form of neutral salts of potassium, sodium, etc., but citric and tartaric acids have a partial effect in this direction. 3. The Plasma can be influenced by acting on the Expenditure. — Thus, by purgation the water, salts, etc., can be influenced through the portal system. By diuretics, the excretion by the kidneys is increased, and by dia- phoretics the functions of the skin are stimulated. The nutritive value of the blood can be increased by sparing the action of the organs of vital energy and of waste, such as the muscles, and the amount of water can be increased by withdrawing a certain amount of blood by the operation of venesection. 4. Influence over the White Corpuscles. — Certain drugs, such as quinine, reduce the number of the white cor- puscles, and cause their movements to cease. Sub- stances which increase intestinal absorption increase Digitized by Microsoft® 112 VETERINARY THERAPEVTICS the production of the white corpuscles, such as aromatic oils, etc. 5. Influence over the Red Corpuscles. — (a) The number of red corpuscles can be increased, and their constituents in hoemoglobin augmented, by attention to food, digestion, air, exercise, etc. The administration of iron in suitable forms directly increases the amount of haemoglobin ; phosphoric acid either alone or in combination with iron or other bases has a similar effect. Substances which either directly or indirectly ' improve the quantity or quality of the hasmoglobin are termed hamatinics. {b) Some substances combine with the hsemoglobin, reduce it to a certain extent, and interfere with its quan- tity and the oxygenating power of the corpuscles, such as arsenic, citrates, and tartrates. The number of the red corpuscles is reduced by lead, which also acts indirectly by interfering with digestion. The oxy-hmmoglobin of the corpuscles is reduced by toxic doses of certain drugs, such as iodine, turpentine, dilute hydrocyanic acid. (c) Oxygenation can be reduced, and the oxygen made to adhere more firmly to the corpuscles, by such sub- stances as alcohol and quinine. Nitrous oxide gas interferes with oxygenation indirectly by taking the place of the oxygen in the corpuscles, and not by com- bining chemically with the hemoglobin. III. Pathological Relations. These are numerous and important, but for our present purpose a short description will suffice. Broadly speak- ing, we have two great pathological conditions of the vital fluid, viz. : 1. Plethora; 2. Ancemia. In plethora there is excess of blood, gentrally found in Digitized by Microsoft® ANAEMIA 113 young fast-growing animals, fed on highly nutritious food and not receiving sufficient exercise. In anaemia there is a deficiency in the quantity of the blood, and a deterioration in its quality ; the albumins are deficient, and the proportion of water is increased. It may depend on various causes, such as insufficient food, imperfect digestion, neglect of hygienic precautions, excessive waste, as in exhausting diseases, etc. As general symptoms we may note paleness of the visible mucous membranes, the pulse feeble, thready and jerky, palpitation being induced by any excitement ; there is impairment of digestion, and the presence of venous murmurs can be detected in the large veins, due to the thin watery blood flowing in the partly-filled vessels with great rapidity. In horses we observe the condition of anaemia in some instances during spring and autumn, when undergoing the process of casting their coats. The animals are not in a proper state of health to perform their work in the usual manner ; they sweat on the smallest exertion ; in some cases there may be anasarcous swellings on the limbs, sheath, abdomen, etc. In considering other pathological conditions of the blood, we may remark that those of the plasma are most common, but are chiefly secondary, i.e., depending on affections of organs from which it obtains its supply, or of some disorders of the excretory organs by which its products are removed from the body. The following conditions will require notice : (a) The Water of the Blood is increased in anaemia, and diminished in cases where its excretion from the system is excessive, such as severe diarrhoea, etc. (6) The Albumin of the Blood is deficient in anaemia, and exists in a defective state in plbuminuria, in 8 Digitized by Microsoft® 114 VETERINARY THERAPEUTICS dropsy, and in parasitic affections of the liver in sheep. In that disease known as ' red water ' in cattle, the albumin of the blood is in a degenerated condition ; and in that affection in horses termed azoturia, or hcemo- globinuria, there is excess of albumin in the blood, which has undergone some complex chemical changes, which render it capable of producing certain morbid phenomena in the system, such as inability to rise, convulsions, and the presence of dark-coloured urine, etc. (c) The Elements of Fibrin may be in Excess or Deficient. — The fibrin is formed in excess in certain acute inflam- matory affections, such as acute rheumatism ; it may also be increased by the application of external irritants. In some exhausting diseases, and in emaciated subjects, the fibrin may also be formed in excess. There is deficiency of fibrin, and, as a result, imperfect coagulation of the blood, in all conditions where there is imperfect oxygenation of the blood. Thus, in subjects which have died from asphyxia the blood is found in a semi-fluid condition, dark in colour, and does not coagu- late until exposed to the air. Various poisons, such as hydrocyanic acid, have a similar effect. In low fevers of a typhoid character, such as influenza in horses, with unsanitary, badly-ventilated surroundings, the blood becomes very fluid in character, and tends to gravitate to the depending parts of the body, forming swellings on the extremities, the abdomen, the head, etc., and the appearance of petechise on the visible mucous membranes, a group of symptoms belonging to that affec- tion termed purpura hceniorrhagica. (d) The Effects of Defective Excretion.— Chyle in a defective condition is a cause of anaemia, etc. When the organs of excretion are disordered or dis- Digitized by Microsoft® NATURAL RECOVERY 115 eased, products accumulate in the blood. Thus, in arrested or defective excretion of urine urea accumulates in the blood, acting as a narcotic poison, and in smaller amounts as an irritant, giving rise to the pathological condition termed urc&mia. Again, in severe pathological conditions of the respira- tory organs, the carbonic acid may accumulate in the blood to such an extent as to cause asphyxia. (e) Deficiency of Haemoglobin — Keduction of Oxy-hsemo- globin. — Deficiency of hEemoglobin may depend on the want of a sufficient quantity of blood as a whole, on want of a sufficient proportion of red corpuscles, or on deficiency of the individual corpuscles in haemoglobin. The result is that the blood is reduced in its oxygenating powers, and the functions of the different vital systems are not performed in a proper manner. Eeduction of oxy-haemoglobin may be brought about by the administration of certain drugs in poisonous quan- tities, such as dilute hydrocyanic acid, iodine, turpentine, phosphorus, etc. Some of these unite with the oxy- hfemoglobin, others seize and combine with the oxygen, the result being that reduced hsemoglobin is left, which becomes dissolved from the corpuscles and diffused through the blood. IV. Natural Recovery. Those affections of the blood which depend on an abnormal condition of the supply and of the excretions will return to a normal state when these influences become normal. The skill of the therapeutist will, how- ever, be often required to assist the efforts of nature. There is a limit to recovery when large amounts of a poison, such as carbonic acid, have entered the blood, and when the htemoglobin has been excessively reduced. Digitized by Microsoft® no VETERINARY THERAPEUTICS v. Therapeutics. The indications under this heading will be based on the facts which we have already laid down. 1. Plethora. — To reduce this condition it is manifest that a proper amount of exercise be enforced, that exces- sive quantities of stimulating foods be withheld, and the excretory organs kept in proper order. 2. Ansemia. — This condition must be treated on general hygienic and dietetic principles, in connection with agents which act directly on the blood. In cases where the albumin of the blood is deficient or degenerated, strict attention must be given to the use of nitrogenous foods, along with the administration of chlorate of potash. In cases where the fibrin is deficient, and there is a tendency to extravasations, etc., drugs which act directly on the blood, such as chlorate of potash with some pre- paration of iron, will be indicated to overcome this condition. If we wish to increase the alkalinity of the blood, such as in cases of rheumatism, we administer salts of potas- sium, sodium, etc. These also combine with the probable cause of the disorder, and by their diuretic action cause its excretion from the system. Certain poisons in the blood, the result of imperfect excretion, will be treated by either acting on the organs at fault, or, if this be impossible, by acting on other organs, and thus assisting in carrying off the deleterious products. Thus, in cases of ureemia we stimulate the bowels and skin to increased action, so as to remove the poison from the system ; also we adopt a similar course in that affection of horses termed azohiria, where there is excess of nitrogenous products in the system, which the kidneys are unable to carry off. Digitized by Microsoft® METABOLISM 117 In deficiency of hcemoglohin the first essential to treat- ment will be careful attention to hygiene and dietetics and the vital functions of the system. We must, in addition, prescribe agents which have the power of restoring the chemical elements of haemoglobin to the red corpuscles. These are preparations of iron with potas- sium salts ; for example, the sulphate of iron with the carbonate of potassium, care being taken, however, that digestion and the action of the intestines are not inter- fered with. In cases of reduction of oxy-hcBinoglobin, such as the effects of poisoning by carbonic acid, hydrocyanic acid, etc., treatment will be of little avail unless it be imme- diate. All that can be attempted is to sustain the circulation and respiration by stimulants and artificial respiration, in hopes to preserve the vitality of the system by making use of the oxy-haemoglobin which may have remained active. CHAPTEE IX. METABOLISM, OR THE PROCESS OF NUTRITION.— THE ACTIONS AND USES OF ALTERATIVES. I. Physiological Relations. Aftee our notice of the different points of therapeutical interest in connection with the blood, we shall now be in a position to consider the complex subject of meta- bolism, which includes the activity of the tissues and the development of force by protoplasm in the presence of blood. This subject is an important one with reference to the actions and uses of many medicinal agents. Digitized by Microsoft® 118 VETERINARY THERAPEUTICS If we take the case of any definite structure, such as a muscle, we shall find the following phenomena in con- nection with it : First, a free and proper blood supply ; second, a certain force during the period of contraction, developing energy and heat, and producing certain chemical substances, such as carbonic acid, water, nitro- genous bodies, and probably urea ; third, after the blood has passed through the muscle, it loses its oxygen and a certain amount of proteids, and takes up the waste pro- ducts for the purpose of excreting them — in other words, it has become venous blood. In this process the molecules of the muscle are mixed with the oxygen and certain elements of the plasma, and an important point to note is that when any living tissue is in combination with metabolic materials, and forming certain results, such as force and other products from them, that the molecules of this living tissue become changed or altered to a certain extent. This change will depend on the character of the blood or plasma supplied. Again, the character of the force generated and of the products produced, and the chemical consti- tution of the active protoplasm of the living tissue, will vary according to the variation in the blood supplied. We thus see that in every organ and tissue of the body there is a relation between the character of the plasma supplied and the character of the protoplasm, the one acting and reacting on the other. According to the structure and functions of the different organs and tissues, we find different substances formed from them, and particular kinds of force dis- played in each case ; for example, secretion, nervous energy, etc. The process of metabolism is still very obscure, and there are many points in ' connection with it requiring Digitized by Microsoft® INFLUENCES OVER METABOLISM 119 elucidation. The precise manner in which the products of digestion are used up in the system, and the forms which they undergo before being broken down into carbonic acid, water, and nitrogenous compounds, is not yet clearly understood. It is not always possible to judge the state of meta- bolism, or the process of nutrition, in the body with any degree of accuracy. We may consider the amount of force displayed, such as the tone of the muscles, the rate of growth, etc., and also the material consumed— that is, the amount of food taken — but when we come to examine the products of metabolism — that is, the excretions — we can glean some very valuable information to help us in clinical study. For example, by an examination of the urine, both chemically and physiologically, we can form a fairly accurate opinion as to the functional activity and condition of the kidneys, and in certain instances, of other organs of the body. II. Pharmaco- dynamics. The power of interference which we possess over the process of metabolism may be considered under the following heads : 1. The Influence over the Blood and its Constituents. 2. By Means of increasing the Excretions. 3. By acting on the Trophic Centres. 4. By the Use of Medicinal Agents. 1. The Influence on Metabolism through the blood as a whole has been already noticed in the last chapter. We can influence metabolism by — (a) Acting on the constituents of the blood by means of supplying certain foods suitable for the purpose in view, as, for example, the special mode of feeding for Digitized by Microsoft® 120 VETERINARY l^HERAPEOTICS horses in training, for pregnant animals, and for those nursing young. We may employ certain agents which act as foods in cases of debility of certain organs ; such agents are termed nutritive tonics. Exajnples. — Cod-liver-oil, alcohol, etc. (b) By increasing the supply of oxygen in the blood metabolism is increased. This can be brought about by a proper supply of fresh air, and by the administration of hamatinio tonics, such as iron. (c) We can increase protoplasmic activity by giving a proper amount of exercise, vyhich includes also a proper amount of plasma and oxygen. 2. By Means of increasing the Excretions metabolism can be influenced ; thus, by acting on the skin, stomach, intestines, liver, kidneys, and lungs, the removal of the products of tissue activity is hastened. 3. By acting on the Trophic Centres metabolism can be influenced, such as by applying to the surface of the body the extremes of heat or cold, or causing stimu- lation of the parts by the application of mustard, etc. ; the impressions produced are carried to the centres by the afferent nerve fibres. The nutritive activity of a part may be increased by acting locally on it, such as by the application of friction, exemphfied by hand-rubbing, and by the use of stimu- lating liniments, composed of ammonia, alcohol, turpen- tine, camphor, etc. The action of such applications is both direct, and also reflex through the medium of the trophic nerves. They cause dilatation of the vessels of the part, increased circu- lation and absorption, and the removal of the products of tissue activity is hastened by the lymphatics and veins. Such agents are termed local alteratives or local tonics. Digitized by Microsoft® ALTERATIVES 121 The modus operandi of poultices and blisters will be discussed ia a future chapter under the heading of Counter-irritation. The surrounding temperature has an important bearing on metabolism. We can influence nutrition by the employment of baths of different temperatures, which act both locally and also through the vessels and nerves. 4. By the Use of Medicinal Agents. — In certain medicinal agents we possess powerful influences over the process of metabolism. These substances when adminis- tered are absorbed by the blood, and reach the tissues, and are taken up by them in a similar manner to that of the nutritive materials. An important fact to note is that certain tissues and organs have the power of attracting and taking up certain medicinal agents. Such agents then are in a state of loose combination with the elements of the parts ; they may form certain chemical compounds with the oxygen present in the tissues ; they are ultimately excreted either unchanged or in an altered chemical condition. During this passage in the tissues they have a certain modifying effect on the force which these tissues are capable of dis- playing. The precise manner in which certain tissues take up and are acted upon by certain drugs we cannot explain. Such drugs are said to have a ' specific action ' on such tissues. For example, iodine and its salts act specially on the glands of the body, and bromine on the nervous system. We have to consider, however, that drugs can act on tissues in another manner besides that just described. They can also act by influencing the vessels and nerves of the part ; ultimately they will probably act on the protoplasm also. Thus, alcohol increases the circulation Digitized by Microsoft® 122 VETERINARY THERAPEUTICS and secretions of the skin by influencing the cutaneous vessels and nerves ; belladonna causes an arrest of the secretion of the submaxillary salivary gland, by paralyzing the terminations of the chorda tympani nerve in the gland, the effects being dryness of the mouth and throat, due to a want of saliva. Alteratives. — It is difficult to define an alterative, although we are aware of the therapeutical effects pro- duced by the administration of the class of drugs included under this heading. We employ such drugs to exert a beneficial effect or alteration in certain morbid conditions of the various tissues and organs of the body. The manner in which these effects are brought about is not always easy of explanation. We may regard alteratives as possessing a certain power of exercising the tissues, ^.e., increasing the nutritive activity, effecting some complex change in the protoplasm and molecules of the part — in other words, increasing the amount of work performed by the part. Not only have medicinal agents this effect, but also diet and surroundings have an important bearing in the same direction. We may divide agents possessing the power of in- fluencing metabolism into two classes : (a) Those which increase Metabolism. — These include such agents as iodine, mercury, arsenic, sulphur; and the manner in which each of these is believed to act will be described under the heading of each drug in the sec- tion on Special Therapeictics. We may regard all as being taken into combination with the protoplasm of the tissues, on which they have a special action, then being removed in the metabolic pro- ducts, and during the whole process a certain change is induced in the molecules of the part, nutrition is Digitized by Microsoft® PATHOLOGICAL RELATIONS 123 hastened, and a healthy exercise of the tissues is brought about. [h) Those which have the Effect of diminishing Meta- bolism. — These agents have-certain specific actions on the blood and on the protoplasm of the tissues. As examples of this class we may take alcohol and quinine. Alcohol is a substance capable of being very readily oxidized in the tissues ; consequently, it absorbs a large amount of oxygen from the cells of the tissues, while it also possesses the power of rendering the oxygen in a firmer state of combination with the red corpuscles of the blood. The efiiects are : oxygenation of the tissues occurring less freely, the activity of tissue changes reduced — points of great therapeutical importance in connection with the employment of this agent in febrile affections. Quinine also interferes with oxygenation, and thus checks metabolism. It also renders the oxygen in a firmer state of combination with the red corpuscles. It is probable that drugs such as quinine, antipyrine, salicin, etc., also diminish the activity of the natural ferments of metabolism. III. Pathological Relations. There are a large number of diseased conditions depending on disorders of metabolism. Briefly, we may remark that the most frequent cause of such disorders can be ascribed to errors of diet and neglect of hygiene. Thus, excess of stimulating food, without proper exercise, has a disturbing influence on general nutrition, as well as on vital organs, such as the liver, kidneys, etc. Want of proper food leads to an anaemic condition, resulting in an enfeebled character of the process of metabolism. Digitized by Microsoft® 124 VETERINARY THERAPEUTICS External influences, such as sudden changes of tem- perature, etc., may give rise to chills, catarrhal affec- tions, etc. The presence of specific organisms in the blood, in- ducing the various phenomena peculiar to each, with the usual symptoms of fever, may be also mentioned as dis- orders of metabolism. Such organisms are supposed to disturb metabolism both by their own life in the tissues, and also by their reproduction, and the products of their changes entering the blood, the result being a general infection of the system, with the general symptoms of fever, viz., high temperature, functional derangement, wasting, and increased excretion. As other examples of disordered metabolism we may mention the different forms of degeneration of tissues, the presence of unnatural growths, such as cancer, and the various forms of inflammatory conditions. IV. Natural Kecovery. Some of the disorders of metabolism will disappear spontaneously, being of a temporary nature. We have to mention two great powers of nature in restor- ing a normal condition of metabolism, viz. : 1. Reaction ; 2. Bepair. In some instances, however, anatomical changes appear in tissues and organs, forming a limit to recovery. V. Therapeutics. Under this heading only a slight sketch of the means at our command can be given, the subject being so exten- sive. The first indication in the treatment of disordered metabolism is to ascertain the cause, and either remove it or act upon it. Digitized by Microsoft® THE CIRCULATORY SYSTEM 125 For example, in the treatment of rheumatism we ensure the action of the bowels, liver, and kidneys, besides prescribing an agent such as salioin, which is supposed to act directly on the specific poison in the system which causes that disease. In other instances we find it impossible to act directly on the cause, so that our only resource is to treat the symptoms. In affections such as certain forms of diseases of the skin we prescribe alteratives, such as arsenic, sulphur, iodide of potassium, etc. These we suppose to have a special effect on metabolism, and a certain beneficial action on the structures of the skin. There are many other affections depending on disorders of nutrition, such as specific diseases— examples, tuber- culosis and cancer, in which our treatment can only be palliative, the chief considerations being, attention to general nutrition, by allowing highly nutritious foods and prescribing agents such as cod-liver-oil, and com- bating symptoms as they arise. CHAPTEE X. THE CIRCULATORY SYSTEM. I. Physiological Relations. The above system is one of great importance to the therapeutist; but for our present purpose it will be su£6cient to notice some points of interest in connection with which we possess certain powers of influence and interference. Digitized by Microsoft® 126 VETERINARY THERAPEUTICS The Pulse has already been considered in Part I., under the heading of The General Symptoms of Disease. Some important points for the student to notice are that — 1. The Heart is a Nervo-muscular Organ possessing automatic action, which depends on the presence of intracardiac ganglia, and that the presence of the blood in the organ excites these ganglia, and the strength of the systole depends on this pressure of the blood. The coronary arteries supply nutrient blood to the heart. 2. The Heart is provided with a Regulating Mechanism, consisting of — {a) The Cardiac Centre in the Medulla. (b) The Vagus or Inhibitory Nerve Supply. (a) The Sympathetic or Accelerator Nerve Supply. (a) The Cardiac Centre is subject to many impulses from a variety of portions of the body, such as from the viscera, skin, central nervous system, lungs, and even from the heart itself ; this centre receives these afferent impressions, which are then reflected to the heart as motor impulses either by the vagus or sympathetic. The aiferent impressions from the heart itself travel through the vagus ; in a normal condition these sensa- tions are not perceived by the individual, but if greatly augmented by any cause, pain, distress, and palpitation occur, being reflected to the praecordium. The cardiac centre is also affected by its blood-supply, depending on the quality of the blood and the blood- pressure in it. (b) The Vagus has an inhibitory or controlling effect over the movement of the heart, its terminations being connected with the intracardiac ganglia. If the vagus be stimulated, the beats of the heart are reduced in force Digitized by Microsoft® THE CIRCOLATORY SYSTEM 127 and frequency ; if this nerve be divided, the heart beats rapidly, ovying to its antagonist, the sympathetic nerve, having full power. This inhibitory action of the vagus can be excited by reflex impressions carried to the medulla, such as by shock or by injuries to the abdominal region, etc. (c) The Sympathetic is the antagonist of the vagus in its action on the heart, it being the augmenting or accelerator nerve. Stimulation of the sympathetic in- creases the action of the heart ; division of this nerve reduces the number of beats of the heart. The sympathetic nerve has extensive connection with the spinal cord, and is not in constant action, while the vagus is in constant action in its inhibitory power over the heart. 3. With reference to the Pulse, we must notice that its frequency and character depends on the length of the diastole or dilatation of the ventricles, as the length of the systole or contraction varies only to a very slight extent under any circumstances. If the diastole be long, an infrequent pulse is the result ; if it be short, there will be a frequent pulse. During diastole the ventricles are being filled from the auricles and veins, and the nervo-muscular structures are being rested and nourished, points of great therapeutical interest, as we shall see further on. 4. The Arteries are controlled by — (a) The Vaso-motor Centre ; (b) Vaso-constrictor Nerves, Vaso-dilator Nerves, besides possessing a local nervous mechanism. (a) The Vaso-inotor Centre is situated in the floor of the fourth ventricle in the medulla; by means of im- pulses passing out from this centre the tone of the Digitized by Microsoft® 12B VETERINARY TUERAPEVTICS bloodvessels of the body is maintained and controlled, they being dilated or contracted as required. Certain centres exist in the spinal cord, and also local centres, all of which are subordinate to the centre in the medulla. The vaso-motor centre is subject to impres- sions from the viscera, surface temperature, sensations, etc., and also is affected by the quality and character of the blood circulating through it ; thus, deficiency and poverty of the blood in oxygen stimulates it, causing contraction of the arterioles and a raising of blood- pressure. It can also be acted on by certain drugs, being either stimulated or depressed. We must, however, be aware that, although stimulation of this centre causes con- striction of the small vessels, it may in some cases result in inhibition of the part, resulting in vascular dilatation, such as is found to occur in certain diseased conditions. Afferent impressions reaching the vaso-motor centre from the heart have a special eiJect, which is of great thera- peutical importance. In cases where the heart is distended with blood, causing distress, or even a tendency to failure of its action, impressions reach the cardiac centre by means of the vagus ; these are transferred to the vaso-motor centre, and impulses are sent to the vessels by the vaso-dilator nerves, with the result that the vessels become relaxed, the blood-pressure falls, and the heart is enabled to empty itself more readily, and becomes relieved. This provision of nature is termed the depressor mechanism of the circulation. (6) Vaso - constrictor Nerves, Vaso-dilator Nerves. — These are distributed to the muscular walls of the small bloodvessels, both sets being under the control of the vaso-motor centre. If the vaso-constrictor nerves be Digitized by Microsoft® THE CIRCULATORY SYSTEM 129 stimulated, the resistance and pressure of the blood will be raised, and constriction of the vessels produced. On the other hand, stimulation of the vaso-dilatora will cause a lowering of the blood-pressure and dilatation of the vessels. Certain vascular areas, such as the skin, may be acted upon, producing either constriction or dila- tation of the vessels, with a corresponding change in the blood-pressure. 6. The Capillaries are subject to the influence of the nervous system, of the blood passing through them, and on the condition of the arteries and veins at either extremity, besides being influenced by the activity of the process of nutrition. 6. The Veins, although probably influenced by nerves, are chiefly acted on in a physical manner. The influences in this respect may be described as follows : (a) The Condition of the Heart. ^li the diastole be short, it follows that the action of the heart will be increased in frequency, consequently there will be less time given for the veins to empty themselves, and the blood pressure will be raised in them. (b) The Condition of the Arteries and Capillaries. — If there be a low blood pressure in the arteries and a free flow through the capillaries, it follows that the pressure in the veins will be increased. (c) The Condition of the Veins has an important effect on the heart and capillaries. Thus, if the blood pressure be high in the veins, with dilatation of their walls, the return of blood to the auricles is interfered with, conse- quently there is weakness of the systole from want of a sufiicient amount of blood, with obstruction to the capillary flow, also disturbance of the process of metabolism. 9 Digitized by Microsoft® 130 VETERINARY THERAPEUTICS II. Pharmaco-dynamics. For conveuience o£ description, we may consider the influence which, we possess over — 1. The Total Volume of Blood in Circulation. 2. The Heart. 3. Tlie Arteries. 4. The Capillaries. 5. The Veins. 1. The Total Volume of Blood in the Circulation may be influenced by venesection. By this means we can reHeve the tension of the whole circulation, and also reduce the blood pressure in the heart and lungs. We must, how- ever, remember that these effects are only temporary, as increased absorption occurs from the tissues and intes- tines into the circulation. 2. The Heart. — We can influence the action of the heart by acting both on its intrinsic and extrinsic nerve- supply. (a) Agents which act on the hitrinsic nervo-muscidar apparatus — Direct Cardiac Stimulants — Direct Cardiac Depressants. A healthy condition of the system, with a proper con- dition of the blood, rendering the coronary circulation active, constitutes a natural direct stimulus to the action of the heart. Certain drugs, such as alcohol, digitalis, ammonia, ether, etc., act as direct cardiac stimulants. Carminatives act as direct and indirect cardiac stimu- lants, the latter depending on reflex action from the gastric mucous membrane through the central nervous system. The heart may be stimulated indirectly by reflex stimulation, such as counter-irritation over the region of the prsecordium, and by inhalation of ammonia, also by the cold douche and by flagellation. Digitized by Microsoft® THE CIRCOLATORY SYSTEM 131 Direct Cardiac Depressants.— These either soothe or depress the intrinsic nervo-muscular apparatus of the heart. They include drugs, such as opium, dilute hydrocyanic acid, aconite, chloral, chloroform, etc. Indirectly we may depress the same apparatus by the use of purgatives, diuretics, and diaphoretics, by warm applications to the prsecordium, by the general hot bath, and by agents which have the power of shortening the diastole of the heart. (b) We can influence the afferent nerves of the heart — ■ that is, the means by which impressions are carried to the brain from the heart itself. These, nerves are depressed by the administration of such drugs as opium, chloral, belladonna, etc. (c) The inhibitory nerves of the heart — i.e., the termi- nations of the vagus in the heart — may be stimulated by such drugs as digitalis, etc., and the action of the heart rendered less frequent. The same structures may be depressed, and the action of the heart increased in frequency, by such drugs as belladonna, hyoscyamus, amyl nitrite. There are many drugs which, given in large doses, have a similar effect. (fZ) The cardiac centre may be either stimulated or de- pressed by certain drugs. It can be stimulated by digitalis, alcohol, ether, chloroform, in their primary actions ; it is also stimulated by belladonna, and by such local measures as counter-irritation and the application of cold douches. It can be depressed by such drugs as alcohol and chloroform after their first stage, also by aconite, chloral, dilute hydrocyanic acid, opium, etc. It is thus clear that we can influence the heart with regard to its frequency by means of acting on the vagus either through the cardiac centre or through its termina- tions. The diastole can bs either lengthened or shortened. Digitized by Microsoft® 132 VETERINARY THERAPEUTICS a matter of great importance in connection with the therapeutics of the subject. We may also remark that all drugs which have the effect of accelerating the action of the heart, if continued in large doses, prove to be cardiac depressants. 3. The Arteries. — We have the power of influencing the arteries by acting on the following structures : [a) The Vaso-Motor Centre. — This can be stimulated by such drugs as alcohol, chloroform, etc., in their primary stages, and temporarily by ammonia, ether, digitalis, etc. It can also be stimulated by such measures as the application of cold to the surface of the body, by counter- irritation to areas of the skin, and by inhalation of ammonia, which stimulates the trigeminus. It can be de-pressed by alcohol and chloroform in the second stages, and by opium, dilute hydrocyanic acid, aconite, belladonna, etc. ; also by the local application of anodynes, heat, etc. (6) By Acting on the Vaso - Constrictor Nervous Mechanism in the Arterial Walls. — This can be stimulated by such drugs as digitalis and strophanthus, in the primary stages, and lead. Locally, by the application of cold, and by evaporation of spirituous and saline solutions, such as by lotions of rectified spirit, acetic acid, or chloride of ammonium. Such measures are termed local vascular astringents. (c) By acting on the Vaso-dilator Nervous Mechanism. — We can bring about vascular dilatation by the action of alcohol, belladonna, nitrite of amyl, etc. Poultices and hot fomentations have a similar effect, as also irritants to the skin, such as mustard, etc. We term such agents local vascular dilators, and in reality they prove to be local circulatory stimulants. 4. The Capillaries. — We can act on capillary areas in a manner similar to that just described. Digitized by Microsoft® PATHOLOGICAL RELATIONS 133 (a) The capillaries can be dilated and the blood-flow increased through them by the application of local heat, friction, and by rubefacients, such as mustard, etc. If the application be more severe, such as by the application of a vesicant, a process similar to that of infl.ammation will be brought about. (6) The capillaries can be contracted, and the bleod- flow through them diminished by the application of extreme cold, and also by astringents, such as lead and silver. Oonstringents have a similar effect, by constring- ing the connective tissue supporting the capillaries ; e.g., tannic and gallic acids, and vegetable substances con- taining these, such as catechu, kino, etc. 5. The Veins. — (a) Directly, we possess but little influence over the veins. We can dilate them by the application of heat, and contract them by cold ; but the reaction will cause dilatation. (6) Indirecthj, by acting on the heart and arteries, we can increase or diminish the pressure in the veins. We can also, by acting on secretion and excretion, lessen blood pressure in the venous system. Thus hydragogue purgatives relieve the portal system, and saline diuretics relieve the renal veins. III. Pathological Relations. Briefly we may regard these under the headings of — 1. Functional Disorders of the Heart. 2. Organic Diseases of the Heart. 3. Hamorrhage and its Consequences. 1. Functional Disorders of the Heart are of very common occurrence in all classes of our patients. It is essential that we must be careful to make a correct diagnosis in such cases, so as to distinguish the symp- Digitized by Microsoft® 134 VETERINAnr THERAPEUTICS toms presented from those depending on organic disease of the heart, and also to ascribe such symptoms to their real causes, in order to treat these disorders in a rational manner. We may divide these disorders of the heart and vessels into three classes, depending on their causes : (a) Those depending on nervous causes, such as excite- ment in animals of a nervous temperament ; also causes acting in a reflex manner through the nervous centres in the medulla, such as derangement of the digestive organs ; or irritation from the presence of parasites in the stomach and intestines. (h) Those depending on changes in the quality and quantity of the blood, such as in the conditions of anaemia, plethora, etc. The nervous centres in the medulla are disturbed, also the vessels and the nervo- muscular structures of the heart itself. (c) Those depending on contamination of the blood, such as in cases of septicaemia, also in the specific diseases. We may also remark that functional disorder of the heart may occur as a sequel to epizootic diseases, such as influenza, the symptoms disappearing when the de- bility, -which is present as a result of the disease, has passed off. It is essential in all cases of functional disorders of the heart that a hasty diagnosis be avoided, as repeated examinations are often required before we can arrive at correct conclusions. It is often surprising what distressing symptoms may be present in cases depending on digestive derangements and the presence of parasites in the stomach and intestines, leading one to the suspicion that such symptoms may be due to organic disease of the heart unless careful observation be persevered in. Digitized by Microsoft® ORGANIC AFFECTIONS OF THE HEART 135 2. Organic Diseases of the Heart are far more common than would be imagined by the information gained from the clinical examination of patients. It is when making post-mortem examinations that we find many instances of well-marked organic disease which had not produced any appreciable symptoms during life, or that these symptoms had not been detected, or had been ascribed to diseases of other organs. The most common organic disease of the heart found in horses and dogs is that of fatty degeneration. This affection is often met with in the case of aged animals in high condition and with insufficient exercise. Of valvular affections we meet with disease of the mitral and aortic valves more often than of the others, the conditions of obstructive and regurgitant lesions being often found together in the latter. As acute affections of the heart we may mention endocarditis, often combined with pericarditis. We may illustrate the effects of a valvular affection by taking the case of a lesion of the aortic valves ; this will also afford valuable indications in the way of treatment. In disease of the aortic valves the course of the pheno- mena induced is progressive. The first effects are that the blood from the left ventricle is obstructed in its passage to the aorta during systole, and regurgitates from the aorta during diastole. In order to overcome this the heart has an extra amount of work to perform, and here we have an example of nature's efforts to combat disease, as a condition of hypertrophy of the muscular wall of the heart occurs, in order to enable it to perform the extra work. This is termed compensation; but after a time, in consequence of the increased demand for nutrition to supply the extra muscular force, this nutrition becomes insufficient, with the result that cam- Digitized by Microsoft® 136 VETERINARY THERAPEUTICS jpensation fails, and then grave symptoms set in. The contraction of the ventricle fails to completely empty the cavity, it becomes overdistended with blood during dias- tole, its walls become stretched, and as a result the cavity is dilated. Other conditions now occur: the mitral valve becomes incompetent, and during systole blood regurgitates into the left auricle, the pulmonary circulation becomes distended, and by this means the right ventricle, and afterwards the right auricle, become impeded in their function. As a result the systemic veins become distended and the circulation in the viscera is interfered with, leading to the occurrence of dropsy, intestinal hgemorrhage, and also to the presence of albu- min in the urine. Eespiration is interfered with, and also the supply of arterial blood to the system, so that the various complications cause a fatal termination. 3. Haemorrhage and its Consequences. — Haemorrhage produces certain effects in the system due to the loss of blood, and also to the fall in the blood pressure. If sufficient in amount, a condition termed syncope, or fainting, will occur. This depends on inability of the heart to supply a sufficient amount of blood to the brain, the result being loss of consciousness and of the power of maintaining the standing position, the ansemia of the brain producing a condition of general muscular paralysis. The same effects are produced by any causes of cardiac failure. In veterinary practice syncope is not a condition of common occurrence. We meet with it in cases of internal hsemorrhage, such as uterine haemorrhage, and haemorrhage as the result of wounds (accidental or after operations). . It may also occur by the accidental en- trance of air into the jugular vein during the operation of venesection. Digitized by Microsoft® THE A TMENT OF CA JiDIA C AFFECTIONS 137 IV. Natural Recovery. There are many compensating mechanisms in the cir- culatory system which tend to bring about a return to a normal condition -whenever this is possible. Thus, we have the reserve force in the heart, the power of com- pensating hypertrophy, the depressor mechanism, etc. Also the methods by which the fluid portions of the blood are removed by the kidneys and bowels, and relief given to the distended vessels. All these are important considerations for the thera- peutist, as they give him valuable indications in the way of treatment. In the case of valvular lesions, when nature fails to give aid, all our efforts can only afford to give temporary relief, and to treat complications as they arise. In the case of horses affected with far-advanced valvular disease, we have to consider that, in consequence of the nature of their work, it is impossible to give that rest which is absoluttly necessary, and also that such animals are dangerous to their owners by reason of their liability to die suddenly when at work, so that in many instances it may not be practicable to advise treatment. In the case of dogs, however, such considerations do not apply. V. Therapeutics. 1. Functional Disorders of the Heart. — Obviously the first step in the treatment of functional disorders will be to ascertain the cause, and then to apply remedies calcu- lated to overcome it. If depending on digestive derange- ments, treatment must be directed accordingly ; if the presence of parasites be the cause, these must be expelled from the system. If depending on an abnormal con- dition of the blood, appropriate means must be adopted Digitized by Microsoft® 138 VETERINARY THERAPEUTICS, to restore the vital fluid to a normal condition ; and if existing after debilitating diseases, general tonics will be indicated. 2. In Organic Diseases treatment can only be palliative, and, as previously remarked with reference to horses, it may not always be advisable to commence a course of treatment with them. In the treatment of valvular lesions, the chief aim should be the prevention and removal of dilatation of the ventricle. Various means are adopted for this purpose, of which the following may be noted : (a) Avoidance of exertion as much as possible, so as to lower the intraventricular pressure. (b) By increasing the Cardiac Poiver. — This can be accomplished by the administration of direct cardiac stimulants, such as digitalis, strophanthus, alcohol, ammonia, etc. At the same time, strict attention should be paid to the digestive system, so as to avoid derange- ments of it, which are a source of danger to the heart. The quantity and quality of the blood is also of import- ance, in order that a proper nutrient supply through the coronary arteries be maintained to the cardiac walls. (c) By increasing the Time of Cardiac Best. — By this means we endeavour to increase the power of contraction of the ventricle, and to prevent over-distension of it, and also to afford a certain amount of rest to the heart. In drugs such as digitalis, strophanthus, etc., we possess valuable agents in this respect. These, besides acting as direct cardiac stimulants, also stimulate the inhibitory apparatus in the. heart and medulla; they lengthen the time of filling the heart, and thus favour the venous flow into it ; the arterial pressure is also raised, as the aorta is more completely filled, and the vaso-motor nerves are stimulated. We can thus clearly Digitized by Microsoft® TREATMENT OF lI^l^MORRn AGE 139 see how they act beneficially in the different conditions ■which exist as a result of lesions of the aortic valves already described. It is obvious that such drugs will be contra-indicattd during the compensation period, but will be of the greatest service when this commences to fail and dilata- tion results. [d) By Treatment of the Symptoms. — These are usually cardiac distress and pain, also pulmonary distress, dropsy, and visceral congestions. In the treatment of cardiac distress, with oppression and pain, cardiac sedatives, such as opium and chloral, may be indicated ; but in the use of these agents great dis- crimination and judgment is necessary, as they may also act as dangerous cardiac depressants. Locally, hot fomentations and rubefacients to the region of the heart, or the application of belladonna, often give relief. In pulmonary distress stimulant expectorants, such as ammonia, are useful ; but our chief reliance in combat- ing this symptom and relieving the pulmonary engorge- ment should be on agents which act on the heart itself, such as digitalis. This agent, acting also as a diuretic, relieves the dropsy which may be present, in a manner which will be described under the heading of The Kidney. In certain cases purgatives will be indicated to relieve the visceral congestions. 3. The Treatment of Haemorrhage. — The treatment of external haemorrhage belongs to the domain of Surgery. The effects will, however, engage our attention under the heading of Syncope. In internal haemorrhage, a condition of very great danger, the therapeutist has to bring different agents to his aid. Digitized by Microsoft® 140 VETERINARY THERAPEUTICS Briefly speaking, internal haemorrhage occurs from the stomach, intestines, lungs and uterus. In the case of the stomach, intestines, and lungs, medicinal agents termed hamostatics are made use of. These agents, also termed styptics, may be classed according to the struc- tures upon which they act. (a) Those acting on the blood, by increasing its power of coagulation or precipitating albumin. By this means hsemorrhage from the part may be subdued. Examijles. — Tannin and substances containing it, such as catechu, galls, logwood, etc. ; also salts, such as alum, acetate of lead, persalts of iron, etc. (h) Those agents producing contraction of the broken vessels, such as acetate of lead, ergot, the local applica- tion of cold or of heat, such as water at 110° to 120°. (c) Those agents which act on the perivascular tissues, constringing them, and thus compressing and closing the bleeding vessels. These include the substances just men- tioned, viz., acetate of lead, persalts of iron, tannin, and substances containing it, etc. In addition to the use of haemostatics in internal haemorrhage, we find it of advantage to administer cardiac and general sedatives with careful judgment, so as to reduce the force but not ihe poiver of the heart, and also to ensure perfect rest. I'or these purposes opium in its different preparations is especially useful. In cases of cerebral haemorrhage, hydragogue purga- tives are useful, by dilating the mesenteric vessels, and thus relieving the cerebral vessels, and also withdrawing a certain amount of fluid from the blood. In some cases of haemorrhage from the stomach, due to portal congestion, we employ purgatives in a cautious manner for a similar purpose. 4.' Syncope. — In veterinary practice, as previously Digitized by Microsoft® VENESECTION 141 stated, syncope, or fainting, is not often seen except in cases of uterine haemorrhage, or as a result of excessive haemorrhage from wounds, etc. In its treatment the chief indication will be to restore the suspended action of the heart by the employment of both direct and indirect cardiac stimulants. The recum- bent position also favours the restoration of the blood and blood pressure in the cardiac centre in the medulla. As direct stimulants to the heart, ammonia, in the form of spts. ammon. aromat., and alcohol are useful. In urgent cases the hypodermic injection of ether must be employed. As indirect stimulants, we may mention the applica- tion of cold to the cranial region, flagellation with wet towels, the solution of ammonia held to the nostrils, etc. In concluding the subject of the therapeutics of the circulatory system, we may give a passing notice to the therapeutical value of venesection. As is well known, this measure was at one time in- discriminately employed in the treatment of all affections, and although rarely practised by some veterinary surgeons in the present day, there is no disputing the fact that in suitable cases it is of the greatest benefit. In cases of pulmonary congestion in horses in high condition, the result of over-exercion when the animals are not in a fit state to undergo it, a moderate abstrac- tion of blood relieves the pressure in the pulmonary vessels and the engorgement of the large veins and right side of the heart, and thus changes the character of the pulse, which, as a result of the conditions mentioned, we find to be small, indistinct, and oppressed. Other affections in which venesection is found of benefit are meningitis, phrenitis in the early stages, and also- in Digitized by Microsoft® 142 VETERINARY THERAPEUTICS that form of brain affection due to reflex action from the stomach known as stomach staggers. It is obvious that in all cases characterized by debility, or those which tend to assume this character, such as epizootic affections, etc., and also in the second stages of the affections mentioned above, venesection is contra- indicated, and cannot act but in a detrimental manner. Local venesection is largely made use of in the form of scarification of locally inflamed areas. It is also availed of by some practitioners in the treatment of laminitis by bleeding at the toe in the affected feet, or at the coronets, though this is a measure as to the beneficial effect of which there is a divergence of opinion. CHAPTEE XI. THE RESPIRATORY SYSTEM. I. Physiological Relations. The function of the respiratory system is to supply oxygen to the blood, and to carry off by expiration the carbonic acid, water, heat, etc., formed in the tissues. The acts of respiration are governed by the respiratory centre, which is situated in the medulla close to the deep origin of the pneumogastric nerves. This centre is affected by impressions carried to it by afferent nerves, not only from the respiratory passages and lungs, but also from all parts of the body by which its activity is modified, and by reflex action the respiratory movements are influenced. The quahty of the blood circulating through this Digitized by Microsoft® THE R ESP IRA TOR Y S YSTEM 143 centre affects it considerably, a deoxidized condition leading to stimulation of the centre, and increasing the respiratory activity. The manner in which the changes in the blood produce these effects is not yet definitely known ; at one time they were ascribed to excess of carbonic acid in the blood. The vagus is the special afferent nerve of respiration, and carries impressions from the whole surface of the respiratory passages to the centre. If these impressions be excessive, they also reach the cerebrum, causing sensations of distress, oppression, or irritation, which are referred more or less to the respiratory organs. An important point to consider is that in a condition of diminished oxygenation of the blood, not only is the respiratory centre stimulated, but also the cardiac and vaso-motor centres, leading to a slowing of the action of the heart, and an" increase in the arterial resistance. We have also to consider that the bronchi are under the control of the medulla, by reason of the motor filaments of the vagus which originate in the respiratory centre supplying the muscles regulating the calibre of the bronchi. By this means impressions originating in the respiratory passages produce an effect on the bronchi. With reference to the mechanism of respiration, it may be stated that in the horse, under ordinary circum- stances, only the last ten pair of ribs take any share in respiration, as the eight true ribs are covered by the scapula ; but when dyspnoea occurs from any cause, the elbows are turned out, and thus other muscles act as auxiliaries, and a certain number of the true ribs assist in respiration. Digitized by Microsoft® 144 VETERINARY THERAPEUTICS II. Fharmaco-dynamics. We can influence the respiratory system in various ways, ■which can be conveniently studied under the following heads : 1. The Air. — By paying attention to the details of ventilation, we can ensure a proper amount of oxygen in the air surrounding the animal ; and by artificially regulating the atmosphere, we can ensure a proper temperature of the respired air. We can also, by the use of inhalations, medicated or otherwise, ' of steam from hot water, produce effects on the respiratory passages. 2. By influencing the Blood and Circulation. — The red corpuscles, being the carriers of oxygen, are important agents in modifying respiratory activity; so that by. acting on these by means of food, drugs, natural in- fluences, etc., we can produce beneficial effects on the respiratory system. The circulation also is of importance in modifying the respiratory functions. 3. By influencing the Lungs and Air-passages — (a) By acting on the Afferent Nerves of the Bespiratory Organs, either stimulating or depressing them. — These nerves are stimulated by ammonia, and depressed by opium, chloral, chloroform, and ether. They are soothed by wa,rm and moist air, and by hot applications to the walls of the chest, and to a slight extent by demulcents. Abnormal sensations connected with the respiratory organs may be modified by these nerve depressants. (&) By acting on the Circulation of the Vessels of the Bronchi. — The circulation can be increased by stimulants to the general circulation, also by digitalis and aromatic oils. The bronchial circulation can be depressed by heat, by general vascular depressants, such as aconite, ipecacuanha, alkalies, etc. Digitized by Microsoft® THE RESPIRA TORY S YS TEM 1 45 (c) By acting on the Bronchial Glands. — We can increase the bronchial secretion by alkalies, especially by ammonia; also by iodine, sulphur, antimony, ipecacuanha, scilla, and also by the group of volatile oils, oleo-resins, and balsams, such as camphor, benzoin, etc. The bronchial secretion can be diminished by belladonna and hyoscyamus. (d) By acting on the Nervo-muscular Structures of the Bronchi and Larynx. — These can be stimulated by those agents vfhich stimulate the afferent nerves of the respira- tory organs. The nervo - muscular structures can be depressed directly, and the bronchial walls thereby relaxed so that the respiratory movements are favoured, by such agents as belladonna, hyoscyamus, opium, chloral, and by the inhalation of warm moist air, such as by the inhalation of steam. 4. By acting on the Respiratory Centre. — (a) We can act directly on the respiratory centre, either stimulating or depressing it. It can be stimulated — that is, the force of nervous impulses proceeding from it may be increased — by ammonia, belladonna, strychnine, and by alcohol, ether, and chloroform in their primary effects. It can be depressed by the full action of alcohol, ether, and chloroform, also by opium, aconite, veratrine. (h) The respiratory centre can be affected by impres- sions reaching it through other nerves than the vagus. It may be stimulated by the inhalation of ammonia, which irritates the fifth cranial nerve. It can be also stimulated by rousing the nerves of the skin, such as by flicking with towels, the application of extreme heat ; also by the application of counter-irritants, such as mustard, etc. On the other hand, a sedative influence may be exerted on the respiratory centre by the applica- tion of warm poultices and fomentations to the walls of 10 Digitized by Microsoft® 14G VETERINARY THERAPEUTICS the chest ; also by applying local anodynes, such as bella- donna and soothing liniments, to the same situation. 5. We can act on the Tracts of the Efferent Impulses from the Respiratory Centre, on the Spinal Centres of the Respiratory Muscles, and on the Nervo-muscular Apparatus of the Chest and Larynx. — These can be stimulated by strychnine, which acts both reflexly and directly by increasing the vigour of the spinal centres. Electricity applied to the nerve trunks, such as to the phrenics, intercostals, or directly to the muscles, also stimulates the same regions. These regions can be depressed by opium, which has the effect of depressing the whole efferent mechanism. The movements of the chest may be controlled directly by the application of suitable bandages to the chest walls, a matter of importance in connection with wounds and injuries of this region. Expectorants increase the amount of the natural secre- tions of the respiratory passages, and also modify their character so as to facilitate their expulsion. In horses and cattle these agents do not appear to have as beneficial an action as in human beings, the best results being obtained from the use of medicated inhalations. In dogs, however, expectorants are of great therapeutical value. Expectorants may act upon the bronchial glands, upon the muscular structures of the bronchi, upon the bronchial circulation and the respiratory centre. Ac- • cording to their action on the circulation, we may divide these agents into 1. Stimulant Expectorants. 2. Sedative Expectorants. 1. Stimulant Expectorants include ammonia, scilla, gum-resins, balsams, etc., demulcents and warm liquid food. Digitized by Microsoft® PATHOLOGICAL RELATIONS 147 2. Sedative Expectorants include alkalies, iodides, ipecacuanha, the inhalation of steam, and hot applica- tions to the walls of the chest. In view of their special actions, we may form other groups of expectorants as follows : 3. Expectorants with a Sedative Effect on Nerves. — These are generally formed by combining expectorants, such as camphor, ipecacuanha, ammonia, etc., with opium, and are of advantage in the treatment of some respiratory affections characterized by irritation and cough. 4. Expectorants ivhich have a Special Action on the Sputa. — (a) Those which increase the water of the bronchial mucus, and thus the liquidity of the sputa; these include saline expectorants, iodine, etc. (b) Disinfectant expectorants include aromatic oils, balsams, etc. ; these are absorbed by the pulmonary mucous membrane, and then excreted from it ; they produce an increased flow of mucus, and exert an anti- septic, deodorant, and disinfectant effect both on the secretion and also on the surface of the mucous mem- brane. The oil of eucalyptus is of special value in this respect, being given internally as well as employed as an inhalation. Disinfectant inhalations can also be made with such agents as carbolic acid, creolin, etc., and are of the highest therapeutical importance, not only pro- moting the discharge from the bronchial tubes in cases of bronchitis, but reducing irritation, and rendering the discharge aseptic. III. Pathological Relations. The diseases and disorders of the respiratory system include a large number of abnormal conditions, to which Digitized by Microsoft® 148 VETERINARY THERAPEUTICS a passing notice can only be given. We may divide them into two great classes : 1. Those depending on changes in the blood and circu- lation, which have been already noticed in Chapters VIII. and IX.- 2. Those depending on changes in the nervo-muscular apparatus, of the respiratory system, also in the lungs and air-passages, the respiratory centre, and the afferent and efferent nerves of communication. In affections of the respiratory organs, such as bron- chitis, pulmonary congestion, pneumonia, pleurisy, etc., we have circulatory, inflammatory, and degenerative changes occurring as predominant conditions, varying according to the stage and severity of the disease, and producing certain anatomical changes in the parts. Thus, in pulmonary congestion we have the pulmonary vessels engorged with blood ; in bronchitis, the bronchial tubes become obstructed by inflammation of their mucosa and swelling, and by the presence of catarrhal products, which may be retained, causing irritation of the nerves, and vessels. In pneumonia, the condition of consolidation renders that portion of the lung incapable of performing its function, while gangrene may result from different causes. In specific affections of the lung, such as tubercle, marked degenerative changes also occur. It is clear that in all such affections the efforts of the practitioner must be directed to the relief of the symptoms, i.e., the effects of the morbid changes, as he has very little power in acting directly on the seat or cause of the disease. Amongst these effects, the following will demand atten- tion : 1. Dyspnoea. — Disturbed respiration varies in degree, Digitized by Microsoft® NATURAL RECOVERY 149 and is a natural effort to increase the oxygenation of the blood when from any cause this process is interfered with. The cohdition is due to stimulation of the respi- ratory centre, which is brought about in two ways : [a) By the blood circulating through it being deficient in oxygen. (6) By exaggerated impressions coming to it from, the lungs and air-passages. These two causes are usually combined, as the morbid changes already mentioned interfere with the proper aeration of the blood in the lungs, and also cause irrita- tion of the pulmonary branches of the vagus. 2. Cough, is a very common symptom of respiratory affections, and has already been noticed in Part I., under the heading of The General Symptoms of Disease. 3. Expectoration. — In horses the products of the res- piratory passages in disease are discharged through the nostrils in the later stages, but in the earlier stages a large proportion passes into the mouth, and is swallowed. The process of expectoration is a most important one to the therapeutist. 4. Pain, Irritation, and Oppression, resulting from ab- normal conditions of the respiratory organs, are symptoms demanding all possible relief. IV. Natural Kecovery. There are, perhaps, no affections which give us clearer indications of the efforts of nature to overcome disease than those of the respiratory system, and it is of the highest importance for the practitioner to recognise these efforts, so as to afford them every possible aid, and to avoid any line of treatment likely to interfere with them. Digitized by Microsoft® 150 VETERINARY THERAPEUTICS The condition of dyspnoea, to a certain extent, is an effort of nature to increase the oxygenation of the blood by increasing the force and frequency of the respiratory movements. We must, however, consider that this con- dition soon tends to aggravate the distress instead of affording relief. Nature endeavours to remove the effects of the morbid influence by removing the excessive secre- tions by expectoration. Vicarious action is another method by which nature endeavours to afford relief — thus, in dyspnoea, auxiliary muscles are called into action along with those of respira- tion, and the healthy portions of the lung tissue take on increased function. V. Therapeutics. In the treatment of respiratory affections hygienic and dietetic measures are of first importance. Pure air, a proper temperature of the surroundings, an allowance of easily-digested nutritive food, and careful nursing of the patient, are details which never should be lost sight of. No hard and fast rules can be laid down as regards medicinal treatment, seeing that we cannot act directly on the organs affected, so as either to remove the cause or cut short the course of the inflammatory action, if such be present. The strength of the patient will demand attention, the condition of the pulse indicating the use of stimulants or otherwise. The excretory organs should be kept in as normal a condition as possible by acting gently on them, such as helping the skin to perform its functions by the use of clothing and diaphoretics, the kidneys by the administration of saline diuretics, and the bowels, should their action become torpid, by the allowance of small doses bf sulphate of magnesia and the use of enemata if necessary. The temperature, as indi- Digitized by Microsoft® TREATMENT OF DYSPNCEA 151 eating the degree of fever present, is a symptom of great importance, and will require appropriate attention by the administration of antipyretics. Above all things, no measures calculated to depress the patient should be adopted, and excessive interference should be avoided. In the treatment of dyspnoea we must carefully inquire into its cause. If depending on acute bronchitis in the first stages, saline expectorants will be of service in liquefying the bronchial secretions ; while the inhalation of warm, moist air, such as steam, will help to overcome the dryness and extreme vascularity of the bronchial tubes. After the early stage is passed, stimulants, such as ammonia with camphor, etc., are indicated, which, besides their expectorant action, sustain the action of the heart and strengthen the respiratory centre. Inhala- tions medicated with disinfectant agents and aromatic oils are of the greatest service, favouring expectoration, and preventing the discharges from becoming putrid or purulent. The external application of heat by means of woollen rugs wrung out of very hot water, and applied in a proper manner to the walls of the chest, gives great relief in cases of this kind. In Dyspnoea from Diminished Respiratory Area, such as occurs in acute pneumonia from consolidation of the lung, we find that the air and the blood cannot come into mutual contact, so that increased respiratory movements 'occur, with acceleration of the cardiac action, the results being that the air is constantly changed and the blood constantly renewed. These are efforts of nature to pro- vide for the aeration of the blood, and the practitioner must endeavour to assist them. Thus, the general system will require to be sustained, and the action of the heart carefully watched, so that stimulants may be administered when necessary, and everything possible secured for the Digitized by Microsoft® 152 VETERINARY TBERAPEUTICS comfort of the patient, the accompanying fever being combated by measures which are not depressing. In Dyspnoea with Spasm, commonly termed ' Asthma,' which is an affection due to spasm of the circular muscu- lar fibres of the bronchial tubes, depending on some irrita- tion of the vagus or respiratory centre, by which reflex impressions pass out to the bronchial muscles, we employ direct depressants to the nervo-muscular structures of the bronchi, such as belladonna, hyoscyamus, etc. This affec- tion in the horse is by some authorities classed with that disease known as 'broken wind,' but others either regard it as a distinct affection or as an early stage of the latter. In dogs asthma is of comparatively frequent occurrence, and often gives rise to very distressing symptoms. Inhalations -of steam often give relief, while hot applications to the walls of the chest are useful ; in severe cases counter-irritation maybe required. Internally, diffusible stimulants and anti- spasmodics give relief, such as spirits of ether or chloroform in small doses, or a mixture of carbonate of ammonia, spirits of ether, with an aromatic, is a useful combina- tion. Powerful respiratory depressants, such as opium, etc., are to be avoided in cases with threatening asphyxia, as they are likely to increase that condition. Cough, depending on respiratory affections, is in some cases an effort of nature to remove some obstruction from the respiratory passages, but often proves a most distressing symptom demanding relief. As far as possible, powerful depressants of the respiratory centre, such as narcotics, are to be avoided in the treatment of respira- tory diseases, and in distressing cough other means should have the preference. In affections such as laryngitis it may be dangerous, if not impossible, to administer remedies in the usual manner, as violent fits of coughing are produced, during Digitized by Microsoft® THE NERVOUS SYSTEM 153 which the medicinal agent (if a fluid) may pass in part into the trachea, causing suffocation or mechanical bron- chitis ; if the agent be in the solid form, such as a bolus, it is quickly returned to the mouth. In such cases we find electuaries of great service ; they can be placed between the molar teeth, and are then gradually dis- solved and swallowed. They produce beneficial effects by their soothing action on the throat, which also ex- tends to deeper-seated parts, such as the bronchi. Elec- tuaries for the relief of cough may contain belladonna, chlorate of potash, etc., made up with honey or syrup. Warm liquid foods should be allowed, and inhalations of steam given without distressing the patient. Pain and Distress, in connection with respiratory affec- tions, are to be treated by external applications to the walls of the chest, such as the application of heat, as already stated. In the early stages of such affections as acute bronchitis and pleurisy, moderate doses of opiates are of great service ; but when the diseased processes are established, we should avoid as far as possible the use of direct respiratory sedatives. The therapeutical value of counter-irritants in the treatment of respiratory diseases is a point on which great difference of opinion exists among eminent authori- ties ; this subject will be discussed under the heading of Counter-irritants in Chapter XV. CHAPTBE XII. THE NERVOUS SYSTEM. Although to the veterinary therapeutist the nervous system is not so important as to the practitioner of Digitized by Microsoft® 154 VETERINARY THERAPEUTICS human medicine, still, it is a system which deserves care- ful attention with reference to the action of drugs and the treatment of various diseases. The physiology of the nervous system is a very exten- sive subject, as its distribution is universal throughout the body, and the student is referred to the excellent manual on ' Veterinary Physiology,' by Professor P. Smith, for a consideration of the chief points in connection with it. For our present purpose, it will be suflScient to notice those portions which are of interest in the therapeutical relations of the system, such as the higher nervous centres, representing sensation, consciousness, and volun- tary motion. I. Physiological Relations. Nervous tissue possesses the power of displaying or discharging force when acted on by certain influences. This power or property is termed irritability. The influence which produces it is termed an irritant, and the act of producing it is termed irritation. If the result of the influence be the display of more force than ordinary, we term it a stimulant, and the action stimulation. If the result be the display of less force than ordinary, we term the influence a depressant, and the action depression. Por practical purposes we may arrange the nervous system on the following plan : 1. The Terminal Nerve-endings on the Surface of the Body and in the Organs. 2. The Afferent Nerves. 3. The Spinal Cord. 4. The Cerebru?n, or Brain Proper. 5. The Efferent Nerves. Digitized by Microsoft® THE NERVOUS SYSTEM 155 In addition to this arbitrary plan, we may add the nervous mechanism of the viscera, which is a portion of great importance. We find that most of the viscera are governed by centres in the medulla, spinal cord, or cerebrum, and that this mechanism is partly reflex ; also that the efferent nerves between these centres and the viscera are intimately connected with the sympathetic nervous system, and that, in addition, the viscera possess intrinsic ganglia, by which their automatic action is chiefly carried on. The following physiological points are of interest with regard to the actions of drugs on the parts named : The Brain consists of motor centres, presiding over the movement of the limbs, and also for the mastication of food, etc. It also consists of sensory centres for the special senses of sight, taste, and hearing, and others for general sensation. These different functions are in addition to the function of the organ as the centre of consciousness, intelligence, etc. In the domestic animals the cerebrum is of small size compared with the posterior parts of the brain and the size of the spinal cord, while in the human being the cerebrum is well developed. As a result of these facts, we find that certain drugs acting on the cerebrum, such as opium, produce marked soporific effects in man, while in the domestic animals such agents produce less depres- sion of brain function, and frequently cause deranged motor function and convulsions. The Spinal Cord possesses three important functions, viz., conduction, reflex action, and origination of nervous force. It transmits sensory impulses to the brain and medulla, and from the latter organs it conveys motor impulses to the muscles, glands, etc. The Medulla contains various centres essential to life. Digitized by Microsoft® 156 VETERINARY THERAPEUTICS such as the respiratory centre, the cardiac centre, etc., which renders this organ one of the most important in the body. Before proceeding to notice the influences which we can bring to bear on the different portions of the nervous system, we have to consider the following physiological states or conditions : 1. Sensation. — This is the result of an impression carried to the cerebrum by an afferent nerve, generally commencing at the periphery, and referred thereto. All organs and tissues in the normal state are sensitive ; but actual sensations do not proceed from them. "When, however, they are disturbed by any cause, perception is aroused, and a condition of pain may be the result. We term the constant existence of sensation in a quiescent state common sensibility . 2. Motion. — The act of movement is generally re- garded as due to an impulse originating in a nervous centre, and being conveyed by an efferent or motor nerve to muscles or muscular organs. Muscular contraction may be produced by stimulation of any part of the efferent or m.otor nerve-tracts. It may also originate in a reflex manner by stimulation of some portion of the sensory nerve-tract, being reflected through the centres. 3. Consciousness is a physiological state partly depend- ing on the presence of perceptions, and partly associated with the intellect and the will. ■ Generally speaking, it will depend on a perfect state of the whole sensory apparatus, but for our present purpose we may regard it as residing in the cerebral convolutions, over which we can exert influence by means of certain drugs. 4. Sleep. — The real nature of healthy sleep is a matter which is not yet clearly understood. It is generally supposed to depend on diminished metabolism of the Digitized by Microsoft® THE NERVOUS SYSTEM 157 gray matter of the cerebrum, either due to a deficient Supply of blood, or an impaired quality of it, or to diminished activity of the tissues following exhaustion. II. Pharmaco-dynamics. This portion of the subject, if considered in detail, would assume very large proportions, as the system is such an extensive one, and the actions of drugs on its different portions are many and diverse. For practical purposes, it will suffice to give an outline of the action of drugs and other measures on the chief portions of the system, giving preference to those which are of use to the therapeutist. It is needless to remark that as the physiology of the nervous system is not yet clear in all portions, so the diseases of it still require further investigation, and as a result the actions and uses of drugs are yet far from being clearly understood. We will first consider the power which we possess over — 1. Sensation. — This will include common sensibility, as well as that of the special senses. (a) Local stimulants have the power of increasing common sensibility, also the sensation of a part, which may even give rise to pain. Most act directly on the nerve fibrils in the tissues, and some may act primarily on the vessels, exciting the circulation as well as the nerves. As examples of local stimulants, we have the applica- tion of extreme heat, extreme cold (temporarily), iodine, volatile oils such as oil of turpentine, and irritants such as mustard, and cantharides in its primary efi'ects. Alcohol and ether, when their vapour is confined, also Digitized by Microsoft® 158 VETERINARY THERAPEUTICS act as local stimulants ; and certain metallic salts, if applied in solution sufficiently strong, have the same effect, such as silver, copper, zinc, etc., acting as caustics or astringents. It is necessary to understand that the sensations pro- duced by local stimulants are in reality central, although they may be referred to the periphery. The higher centres are stimulated, and the impulses, while being carried to the cerebrum, also act partly on the spinal and medullary centres, producing reflex impulses which may act on muscles and the viscera. Thus we see that sensory impressions, especially irri- tating ones, stimulate not only consciousness, but also the vital centres in the medulla, and through them some of the important viscera. For example, the cold douche rouses consciousness, and also excites the respiratory centre, causing increased respiratory movements. It will thus be seen that local stimulants may become general stimulants. (b) Local anesthetics reduce the sensibility of the terminal nerve-endings, and finally remove their power of receiving impressions. When used for the relief of pain, they are termed local anodynes. Some agents directly depress the nerve fibrils, such as belladonna, aconite, cocaine, opium ; others, such as alcohol, ether, volatile oils, etc., have a similar effect when their action is prolonged. Moderate cold, such as that produced by the evaporation of ether, acetic acid, etc. — also certain saline solutions, such as that of chloride of ammonium — possess an anaesthetic effect on the parts to which they are applied ; while extreme cold will cause absolute anaBsthesia of the part. Moderate heat reduces the irritability of nerves, while extreme heat prolonged destroys it. Digitized by Microsoft® INFLUENCES OVER MOTOR SYSTEM 159 We employ certain agents, such as poultices, to act as local anodynes, which effect they bring about by com- bining the properties of heat and moisture. The heat relieves the pain by acting on the bloodvessels, dilating and relieving them, promoting osmosis and the migration of corpuscles, an effect which is assisted by the presence of moisture. (c) We can act on the tnonhs of the afferent nerves. By the use of certain drugs, such as opium, we can interfere with the carrying of impressions from the periphery to the sensory centres by depressing the nerve- trunks themselves. We may mention a familiar surgical operation — viz., neurotomy — which relieves pain and lameness by section of the nerve, thus preventing painful impressions being carried to the sensory centres from the diseased part. (d) We can act on the sensory and perceptive centres themselves by that group of agents termed narcotics; these include general anaesthetics and general anodynes, which will be noticed presently under the head of Gon- sciousness. Among the group of narcotics, we find some agents, such as opium, which interfere with the afferent impres- sions from all portions of the system— that is, at their formation, in the course of their conduction, and at their entry to the sensory centres. 2. Motion. — We possess more power over that portion of the nervous system presiding over motion than over sensation, because we can act on motor parts both directly and also in a reflex manner — viz., by local irritants producing muscular movements, and local depressants arresting them. We find that different drugs act on different portions of the motor apparatus. Digitized by Microsoft® 160 VETERINARY THERAPEUTICS {a) Motor stimulants may act on the motor convolutions of the cerebrum. Examples. — Alcohol in moderate doses, and chloroform and ether in their primary stages. They may act on the medulla. Thus, ammonia, bella- donna, and strychnine excite the movements of the respiratory muscles by acting on the respiratory centre, and ether and chloroform in their primary stages have a similar effect. They may act on the motor centres of the spinal cord. Thus, strychnine produces convulsions by powerfully stimulating these centres. Local motor stimulants act on the terminations of the nerves, the terminal apparatus, and the muscles them- selves. As examples, we have the employment of hand- rubbing to parts, the cold douche, etc., which rouse the local circulation, and increase muscular nutrition and activity. Electricity is also in use as a local motor stimulant, and strychnine possesses a similar action. (b) Motor Depressants. — Large doses of alcohol, ether, and chloroform depress and finally paralyze the motor convolutions of the cerebrum, and thus completely arrest all voluntary movements. The motor functions of the medulla are depressed by opium, aconite, chloral, etc., and by large doses of alcohol and chloroform, which ultimately produce paralysis of the respiratory centre, and cause death by this means. The motor centres in the spinal cord are depressed by physostigmine and other drugs, the result being paralysis of the limbs when large amounts are administered. The motor nerves themselves are depressed by conium and other drugs, which cause paralysis through these channels when administered in sufficient amount. The motor nerve-endings are depressed by belladonna Digitized by Microsoft® NARCOTICS 161 and its allies, this effect being more marked in the case of involuntary muscles. 3. Consciousness. — Consciousness is readily acted on by various influences, but for practical purposes it is only necessary to refer to three means which we possess by which we are enabled to bring about desired results in connection with it : (a) We. can rouse consciousness by powerful and also by painful impressions, such as the use of the cold douche, or the application of an irritant, such as mustard, to the surface ; also by the inhalation of ammonia. (b) We can reduce consciousness by the use of cerebral depressants, such as by the bromides, which diminish reflex excitability, and give the nervous centres a certain amount of rest. (c) We can remove consciousness by the use of general ancssthetics. These agents directly depress the nervous tissue of the convolutions, arresting their functions, removing sensibility and consciousness. General anaesthetics belong to a group of drugs termed narcotics. Narcotics possess a very complex action, influencing both sensory and motor portions of the nervous system, and also acting on most of the viscera. All narcotics, pushed to a certain extent, produce a condition of unconsciousness ; but they do so in such a different manner that we are enabled to select some out of the number which have been proved by experiment and experience to be safe for use as general aneesthetics. This selection is made as a result of our knowledge of the precise action of these agents, and of the manner in which they involve the different portions of the nervous system. We may divide narcotics into two classes for this purpose : 11 Digitized by Microsoft® 162 VETERINARY THERAPEUTICS 1. Those which act primarily on the convolutions of the cerebrum, first stimulating, then depressing, and finally arresting their functions, producing the condition of unconsciousness. The vital centres in the medulla are also depressed, but until consciousness is completely removed, no serious depression in the vital centres occurs. Chloroform and ether act in this manner, and are hence the agents rnost commonly used for the purpose of general ana3sthetics. 2. Those agents which involve the cerebrum and the vital centres in the medulla at the same time, so that before the condition of unconsciousness is produced there is dangerous depression of the centres of respira- tion and circulation in the medulla. As examples of such agents we may give opium and chloral. It is needless to remark that such drugs are not used for the purpose of removing consciousness, but are frequently employed, and are of great importance when prescribed in suitable doses, as general anodynes. For such purposes we employ them to arrest perceptions of pain, to induce sleep, and to soothe and prevent pain in the great vital organs of the body when such are dis- ordered or diseased. Hypnotics are agents which promote or produce sleep, and include narcotics, such as opium, chloral, etc., also bromides. They do not act so readily on animals as on man, in consequence of the cerebrum of the former not being so well developed as in the latter. We may remark that certain nervous depressants, such as aconite, paralyze the medulla before they remove consciousness, and consequently are dangerous agents, never employed for general ansesthi-tic purposes, and requiring great care in their use as nervous sedatives. Digitized by Microsoft® PARALYSIS 163 III. Pathological Belations. In considering the pathological relations of the nervous system, it will be sufficient for our purpose to notice the principal symptoms to which the varied morbid conditions give rise. 1. Disturbances of Sensation — Pain. — We are aware that the condition termed pam will depend on a great variety of causes, and may arise from different sets of organs, and may be due directly to the part to which it is referred, and where it originates, or by reflex action affect other regions. Briefly we may state that whatever tissues or organs are affected, giving rise to the condition of pain, we may regard it as originating in the nerve- supply, connecting the periphery with the sensory centres in the cerebrum. Severe pain produces very serious effects if allowed to go on unchecked. It is a powerful depressant of the nervous centres and of vital organs ; and such actions, taken in connection with the morbid condition on which the pain depends, will clearly show the student the great importance of pain as a general symptom of disease. 2. Paralysis. — This is a symptom depending on various morbid conditions of the nervous system. Paralysis may affect different portions of the body : thus, we may have paralysis of the posterior extremities, paralysis of the intestines, paralysis of the bladder, etc. We find this condition in a large variety of diseases, of a diversified nature. Thus, we have inability to rise in that affection termed azoturia in horses, also in injuries to the spinal cord. In cattle we find it in cases of milk- fever; and in dogs we find paralysis of the hind ex- tremities in some cases of impaction of the intestines, also in the later stages of rabies. Digitized by Microsoft® 164 VETERINARY THERAPEUTICS 3. Excessive Motor Activity. — Under this heading are included conditions such as spasm, convulsions, etc. ; also disturbed movements of the viscera may be included. The conditions may occur in a large number of affec- tions, and depend on various causes, being due in some to a morbid state of any part of the motor tract from one extremity to the other, and in others to some dis- turbance of the sensory area, which produces effects by acting reflexly through the centres. 4. Disturbances of Consciousness. — These include the conditions of — {a) Unconsciousness, which may depend on direct injuries to the head ; on interference with the blood supply to the cerebrum; such as is seen in fainting due to haemorrhage ; on organic diseases of the brain, and as a result of narcotic poisons. (6) Delirium, and excitement, which are conditions found to occur in many diseases, and leading to a state of exhaustion. Many poisons also produce these con- ditions. IV. Natural Recovery. Many disorders of the nervous system not depending on organic changes have a tendency to disappear when the cause is removed either by natural means or when these are aided by the therapeutist. As it is difficult in many instances to ascribe the symptoms presented to their real cause, it is clear that under such circumstances our efforts can only be directed to the alleviation of the conditions placed before us. One important point never to be lost sight of is that severe pain should always be checked as early as possible, no matter what it depends on. Digitized by Microsoft® THE USE OF ANODYNES 165 V. Therapeutics. In considering this portion of the subject we will follow the headings laid down in the previous section, which, as we have stated, deal only with a view of the principal symptoms. 1. Disturbances of Sensation — the Use of Anodynes. — Pain, as the chief indication of disturbances of sensation, must be rationally treated by first ascertaining its cause as far as this is possible. As we have already remarked, pain acts as a powerful depressant of the centres and viscera, and hence the aim of the therapeutist should be to relieve this distressing symptom as speedily as possible, taking care, however, to accomplish this by means which will not act in a manner detrimental to the general system, or in a manner likely to increase the gravity of the affection on which the pain depends. In veterinary practice we have to consider that not only is the "relief of pain necessary from its depressing effects on the vital systems, but also that the patients may seriously injure themselves by rolling about in a reckless manner in their endeavours to obtain relief ; besides, there is the danger to the attendants from the latter, and also the impossibility of administering medi- cinal agents. Pain is exhibited by animals' in a variety of ways, depending on the species and the individual temperament of the patient. In the horse excitement generally pre- vails, either rolling about violently or walking round his stall, and lying down carefully, various postures being assumed depending on the nature of the affection. Clinical observation and experience alone will enable the student to discriminate between the varieties of pain exhibited, and to ascribe the symptoms to their true Digitized by Microsoft® 166 VETERINARY THERAPEUTICS cause. He must be careful to distinguish betweeu the manifestations of pain depending on abdominal affec- tions and those due to affections of other organs, such as of the kidneys, pleurae, brain, etc. Correct diagnosis in such cases must be made by paying attention to the general symptoms presented, and also to the history of the case, and to special symptoms, which, if not present at the time of examination, may become apparent as the disease is developed. The con- ditions of delirium, excitement, etc., depending on affec- tions of the brain, whether of its substance or of its coverings, must be distinguished from similar effects due to other causes. It is needless to say that such distinctions are by no means clear when we consider, for instance, that affec- tions of the stomach may, by reflex action, produce marked disorder of the brain, causing a combination of the evidences of pain and delirium. Then, again, we have in certain affections, such as azo- turia, the occurrence of violent convulsive movements, in severe cases continued until the patient becomes worn out, evidently due to some morbid cause acting on the nervous system. Whether pain really occurs or not in such cases we cannot definitely say, because our patients do not possess the power of speech. Chronic degenerative 'diseases of the kidneys will also, in some cases, produce various degrees of pain, evidenced by the peculiar postures assumed by the patients. In cases of volvulus and intussusception of the intes- tines the most violent struggles are often witnessed, the pain becoming so intense that the patient seems incap- able of controlling his actions. In cases of brain affections, whether occurring as primary affections or due to reflex irritation from the stomach, the horse becomes so violent in the first stages Digitized by Microsoft® THE USE OF ANODYNES 167 that it is impossible to approaeli him or to administer medicines. In cattle we also find the evidences of pain either shown in great excitement, with excessive motor move- ments, or by great dulness accompanied by a grunt or low moan frequently repeated. In dogs pain is manifested either by low moans or by shrieks, depending on severity. Different postures are also assumed. The alleviation of pain leads us to inquire into the use of Anodynes. These are agents prescribed for the relief of pain. To make use of anodynes in a scientific manner it is necessary to arrive at a correct diagnosis — that is, to ascertain the cause of the pain and to remove it, and to act on the effects which remain. The student will clearly see that in all cases this will not be possible, especially so when we have to depend on objective symp- toms for a diagnosis. Nevertheless, there are certain conditions where pain exists, and where we can remove it by the employment of what are termed indirect anodynes ; these attack the cause of the pain, while they do not act directly on nervous tissue. For example, in the case of local affec- tions characterized by pain, such as an abscess or a foreign body in a part, we make use of surgical means of relief, also of poultices, warm fomentations, etc. But even local affections sometimes require the use of either local direct anodynes or general anodynes. Again, we find that local irritants, such as mustard, etc., may become local anodynes, supposed to be due to certain actions, such as exhaustion of the irritability and con- ductivity of local nerves and to dilatation of the vessels, etc., effects which will be described in the chapter on Counter-Irritation. Purgatives may act as indirect anodynes in some cases, Digitized by Microsoft® 168 VETERINARY THERAPEUTICS such as in impaction of the stomach or in spasmodic colic due to the presence of irritating ingesta ; these agents remove the cause. But it is often necessary. to combine with them anodynes in order to remove the effect — i.e., the pain. Local Anodynes are employed to reduce the irritability of nerves by local means ; such are belladonna, opium, cocaine, and also the hypodermic injection of morphia, which acts both locally and generally. General Anodynes are a most important group of medi- cinal agents in veterinary therapeutics. They relieve pain, no matter from what source, by depressing the sensory centres in the cerebrum, or by diminishing the conductivity of the sensory nerves, or by a combination of both methods. Some such as chloral hydrate act as pure and powerful hypnotics — that is, cause sleep, and prevent the perception of pain by their action on the sensory centres of the cerebrum. Others, such as opium, and its active principle, morphine, produce a paralyzing effect on the sensory nerves of all organs, and also act as hypnotics in some animals. As we shall see, however, when treating of the special therapeutics of opium and its alkaloids in the majority of cases in horses, instead of a hypnotic effect, these drugs produce excitement, and act as oerebro - spinal stimulants, even when administered in large doses ; and as such effects are productive of harm by reason of their depressing action on the nervous system at a time when it requires rest, we have to depend on another drug — viz., cannabis indica — which possesses the properties of acting as an efficient anodyne, both by producing direct hypnotic effects as well as depressing the sensory nerves. A pure hypnotic, such as chloral hydrate, although pro- ducing sleep by its action on the convolutions of the Digitized by Microsoft® TREATMENT OF PARALYSIS 169 cerebrum, has little effect on the peripheral sensory nerves ; hence, when the patient awakes from the sleep the .pain may not be relieved, and suffering may continue as before. "We may also refer to the use of General Anasthetics in surgical operations ; these will be considered under the Special The7-a2X^itics of Chloroform, Ether, etc., in Part III. 2. Paralysis. — Paralysis must be treated according to the nature of the affection on which it depends. In veterinary practice it is well to bear in mind that if there is no reasonable prospect of a return to a normal con- dition, by which the patient will be enabled to be of practical use, treatment is of no avail, as a paralyzed animal is of no value. Paralysis occurs most commonly in animals in the form oi paraplegia, generally depending on some affection of the spinal cord, producing a defect or loss of power in all parts posterior to that affected. It may depend on various causes, such as injury or fracture of the vertebras, and also in reflex or functional causes, such as in that affection of horses termed azoturia, and in dogs in some cases of intestinal obstruction and impaction. General paralysis may occur from lesions of the cerebrum or of its coverings. As an example of local paralysis in the horse, we may mention that of the branches of the facial nerve, pro- ducing dif&culty in prehension and mastication. In cases affecting the spinal cord and nerves, nerve tonics, such as strychnine, are indicated, local treatment being also of value. In cases depending on cerebral affections, treatment must be adopted according to the nature of the lesions, stimulants being indicated in some instances, and cerebral sedatives in others. Digitized by Microsoft® 170 VETERINARY THERAPEUTICS 3. Excessive Motor Activity. — Spasms, convulsions, etc., are also rationally treated according to their cause. We meet in young dogs cases of convulsive fits due either to teething or to the presence of parasites in the intestinal canal. Such cases are treated by aperients and stomachics, and by anthelmintics, according to the cause. Cases of epilepsy are met with in dogs, in which instances the administration of the bromides is often of service. In affections such as tetanus, in which the correct pathology is not yet discovered, various means of treat- ment are adopted ; but it cannot yet be said that the use of one drug gives better results than another. In cases of convulsions the exact cause of which we cannot determine, it may be necessary to prescribe drugs such as opium, chloral hydrate, cannabis indica, etc., to abate the violence of the symptoms. In cases of such affections as azoturia, where the convulsions depend on some deleterious agent acting on the nervous system, it is of the greatest importance to ensure the action of the various excretory organs, such as the bowels, the skin, and the kidneys, by the use of purgatives, diaphoretics, and diuretics when necessary, avoiding narcotic agents as much as possible until the other means fail. 4. Consciousness. — In cases where delirium is a promi- nent symptom, cerebral depressants, carefully regulated, are indicated, such as chloral, bromides, etc. In loss of consciousness, we must clearly inquire into the nature of the case. If the condition be due to injuries of the head, our attention should be directed to the state of the heart and the respiratory system, which may become depressed along with the convolu- Digitized by Microsoft® THE KIDNEYS 171 tions of the cerebrum, the centres of respiration and circulation bein^ involved by the injury. In such cases restorative measures must be employed, including cardiac stimulants and artificial respiration if necessary. But in cases of loss of consciousness, where the vital centres are not seriously depressed, we should avoid stimulants as much as possible, as they are likely to increase the existing injury to the brain by stimulating the circula- tion through it, when it should remain in a state of quietude. CHAPTBE XIII. THE KIDNEYS. Although organic affections of the kidneys are by no means so frequent in our patients as in human beings, still, a consideration of these important organs is neces- sary, as, independent of chronic diseases, there are many abnormal states met with which demand the attention of the therapeutist. Also, the kidneys, being very im- portant organs of excretion, can be availed of as auxiliaries in the removal of deleterious materials, depending on affections of other organs. I. Physiological Relations. The function of the kidneys is to remove from the blood and from the system the waste and poisonous products of the body, the excretion thus formed being termed the urine. Briefly, the urine may be stated to arise from two portions of the kidney. 1. The Bulk of the Water of the Urine is removed from Digitized by Microsoft® 172 VETERINARY THERAPEUTICS the blood by means of the Malpighian bodies, the blood pressure in which is always high, because the eil'erent vessels are smaller than the afferent. The watery portion then transudes into Bowman's capsule, and thence into the tubules. 2. The Solid Portions of the Urine, viz , the urea, uric acid, hippuric acid, and many salts, dissolved in a small amount of fluid, are separated from the blood by the cells of the convoluted tubules. These epithelial cells separate from the capillary vessels which surround them the organic and inorganic materials mentioned, and these join the water which is passing through the tubules derived from the Malpighian bodies. According to Ludwig, there is a partial reabsorption of the water, which is excreted by the Malpighian tufts. The renal vessels are under the control of the vaso-motor system of nerves, and there are no recognised secretory nerves of the kidneys. The Secretion of Urine consists of a filtration theory, i.e., the existence of a difference in pressure between the blood in the Malpighian bodies and the tubules ; and also on the elective power possessed by the epithelial cells of the tubules, which remove the organic and inorganic matters from the same blood. The Amount of Urine depends on the nature of the food, the quantity of fluids taken, and the activity of the bowels and skin. The secretion of urine is increased, during the period of digestion, by cardiac stimulation, and also by contraction of superficial bloodvessels, such as by the action of cold on the skin. The organic matters are increased by nitrogenous food, and the activity of the renal epithelium will depend on the activity of the circulation and on the quality of the blood. The following points are also of importance : Digitized by Microsoft® DIURETICS 173 The Quantity of Urine secreted by the horse is about Q^ pints for the twenty-four hours. In cattle the amount is 21 to 28 pints for the same period. Garni vora excrete by the kidneys the major portion of the water they drink, while herbivora excrete the greatest part by the lungs. The Reaction of the Urine in herbivora is alkaline, the alkalinity being due to the presence of carbonate of potash. In carnivora the reaction is acid. According to Professor Smith, uric acid does not occur normally in the urine of the horse, and he regards uric acid in herbivora as replaced by hippuric acid. II. Pharmaco-dynamics. We can act on the urinary excretion by means of agents termed diuretics. Diuretics may be defined as agents which act on the kidneys and increase the secretion of urine. Obviously, from what we have just noticed with regard to the physiological relations of the kidneys, their functions can be increased in a variety of ways, which, for con- venience of description, we may classify as follows : 1. Agents which increase the Volume of the Urine — that is, the amount of water excreted from the glomeruli. Evidently this will be accomplished through the circula- tion. 2. Agents which affect the Excretion of the Urinary Solids. — These will act chiefly through the blood itself. 1. The Agents which increase the volume of the Urine produce their effects in different ways, as follows : (a) By raising the blood-pressure in the general arterial system, including the renal arteries, without affecting the pressure in the veins. This can be accomplished by increasing the amount of Digitized by Microsoft® 174 VETERINARY THERAPEUTICS fluids ingested, which increases the amount of water in the system ; also by the administration of cardiac stimu- lants, such as alcohol, digitalis, ammonia, etc. Such agents are termed cardio-vasculM' diuretics. The action of cold on the surface of the body will produce a similar effect by constricting the peripheral vessels. (6) By Agents which dilate the Benal Arteries. — These cause increased quantity of blood in the renal arteries, while the general arterial pressure and that in the renal veins remains unaltered, These act locally on the vaso- motor nerves of the kidney, causing depression, and con- sequently dilatation of the renal arteries. They include digitalis in the second stage of its action, spirits of nitrous ether, volatile oils and resins, such as turpentine, cam- phor, etc. ; also agents such as alcohol, belladonna, etc. The action of cold on the surface of the body produces reflex dilatation of the renal vessels. All these agents are termed local vascular diuretics. By combining agents in classes (a) and (&), a more pro- fuse volume of urine will be the result. 2. The Agents which affect the excretion of the Urinary Solids may be divided into two classes. Both influence the activity of the renal epithelium, and hence the excre- tion of solids and a certain amount of water. (a) Those lohich affect the Belial Epithelium through the General Gomposition of the Blood. — General measures, which include the composition of the food, the perfection of the process of digestion, the action of the liver, etc., and the causes producing such normal performance of functions, all have an effect in altering the composition of the urinary solids. The chemical reaction of the urine is not affected by the administration of the mineral acids, as the majority are excreted in the form of neutral salts. The vegetable acids, such as citric, tartaric, and acetic Digitized by Microsoft® DIURETICS 175 acids, combine with alkaline bases, and are excreted as alkaline carbonates. The administration of alkalies produces an alkahzing effect on the urine — that is, in the case of carnivora. Ammonia has not this effect, as it is broken up in the system. (h) Those Agents which act in a Special Manner on the Benal Einthelium. — Potash stimulates the renal epithe- lium, and is excreted as the carbonate. Soda in certain of its salts, such as the phosphate, has a similar effect, but in a far less degree. Magnesia and calcium are also special stimulants of the renal epithelium. All these salts mentioned, while acting as special stimulants of the renal epithelium, also carry with them a certain amount of fluid from the venous plexus around the tubules, and thus produce a condition of diuresis. Such agents are termed saline diuretics, and are of great importance to the therapeutist. We do not recog- nise them as directly affecting the renal circulation, but as acting indirectly by their influence on the venous plexuses around the tubules, thus producing effects on the renal circulation, and especially on the blood pressure in the veins. In addition to saline diuretics, we possess a group of medicinal agents in the aromatic oils, oleo-resins, and balsams, which have a special effect on the renal epithe- lium. These are excreted by the renal epithelium in part, either unchanged or altered by decomposition during their passage. They also carry away a certain amount of water. This action varies according to the agents employed. Some, such as turpentine in large doses, may in some cases diminish, in others increase, the bulk of the urine, and may even produce haemorrhage from the glomeruli. Digitized by Microsoft® 176 VETERINARY THERAPEUTICS 3. Renal Sedatives or Depressants diminish directly the activity of the renal epithelium, producing their action by their influence through the blood. We may mention opium and its alkaloid, morphine, as possessing this power in a marked degree. III. Pathological Relations. Chronic affections of the kidneys are rare in veterinary practice, and acute inflammatory affections of these organs cannot be said to be of common occurrence. There are, however, disorders of the renal functions commonly met with, characterized by changes in the character, composition, and volume of the urine. As examples of these, we may give azoturia, or hgemo- globinuria, and diabetes insipidus in horses, and that affection termed ' red water,' or hasmo-albuminuria, in cattle. As cases of chronic inflammatory affections of the kidneys are sometimes met with both in horses and dogs, it is necessary to study the pathological relations of this system as briefly as possible on the following lines ; 1. Disorders of the Fluid Portion of the Urine depending on Changes in the General Blood Pressure. — These may be referable to — (a) Diminution of the General Arterial Pressure. — This condition may be due to disease of the heart — e.g., dila- tation — by which the arterial pressure is lowered and the venous is raised ; so that, as regards the kidney, the pressure is lowered in the afferent vessel of the glomerulus, and raised in the efferent vessel. The result is passive congestion of the kidneys. The urine is lessened in amount, both of fluid and also of the total Digitized by Microsoft® RENAL AFFECTIONS 177 amount of solids; it may contain albumin, and blood derived from the engorged veins. {b) Increase of the General Arterial Pressure. — This condition occurs in that form of chronic disease of the kidney known as the granular or contracted kidney. In such a case, the left ventricle of the heart is hyper- trophied, and the arterial tension high at first, succeeded by dilatation of the heart. The results are : The urine is greatly increased in volume, light in colour, and of low specific gravity, and may contain traces of albumin. There is a constant condition of diuresis. 2. Disorders of the Fluid Portion of the Urine depending on Changes in the Local Blood Pressure. — These may be referable to — (a) Certain Nervous Conditions. — These disturb the blood pressure in the kidney by acting on the renal vessels, and thus influencing the fluid portion of the urine. As examples, we may give hysteria, characterized by alternate profuse and deficient secretion of the urine. Also diabetes insipidus, in which there is disordered innervation, probably depending on defective assimilation, due to improper food ; the vaso-motor centres become disordered, the renal vessels dilated, the result being that there is an excessive amount of urine secreted, pale in colour, and of low specific gravity ; great thirst is also a prominent symptom in this affection. (b) Morbid Conditions of the Benal Bloodvessels. — These may affect either the glomeruli, the arteries, or the veins ; they are found to occur as one of the patho- logical conditions of that affection termed Bright's disease. The results as regards the volume and con- stitution of the urine will depend on the portions in- volved, and on the severity of the diseased process. We may also refer to another cause acting on the 12 Digitized by Microsoft® 178 VETERINARY THERAPEUTICS renal bloodvessels — viz., the presence of abdominal en- largements. These may cause pressure on the trunks of the renal vessels, and thus interfere with the renal circulation, resulting in the presence of albumin, blood, etc., in the urine, or in some cases there may be suppres- sion of urine. 3. Morbid Conditions of the Secreting Epithelium of the Kidney. — These are among the lesions also found in cases of Bright's disease. The cells lose their function, becoming diseased ; they obstruct the tubules, and press upon the venous plexus, causing interference with the circulation of the blood, and also with the filtration of the fluid portion of the urine through the glomerulus. The results are : The urine becomes lessened in volume, and of high specific gravity. It contains albumin, prob- ably derived from the venous plexus, and blood, either from the latter or from the glomerulus ; and also casts of diseased cells, fibrin, etc. The following serious results may occur : The urea accumulates in the blood, the general circulation is interfered with, the heart becomes affected, and the fluid portions of the blood escape into the tissues and serous cavities, constituting dropsy. These are some of the phenomena met with in that form of Bright's disease known as the large ivhite kidney. The student should compare the character of the urine wibh that described in subsection (6) — i.e., the contracted kidney, which is another form of Bright's disease. 4. Eenal Affections depending on Abnormal Conditions of the Blood. — The urinary secretion may become de- ranged by influences other than changes in the kidneys themselves. Thus, the blood may be in an abnormal state as the result of dyspepsia or from hepatic disorder, and the urinary secretion may be greatly modified as regards its composition and reactions. Digitized by Microsoft® RENAL AFFECTIONS 179 We may refer to the following disorders as examples of cases of this nature : (a) Oxaluria — an affection met with in horses, con- sisting of debility, loss of flesh, and the presence of oxalate of lime in the urine, which is clear and pale in colour, frequently passed, and acid or neutral in reaction. The causes are : Irregularities in feeding, improper diet, and impaired digestion as a result. It is also said to be produced by food containing an excess of saccharine materials, such as turnips, carrots, etc. {h) Azoturia — a condition characterized by spasms of the large muscles of the posterior part of the body and of the limbs. The urine is dark-coloured, of high specific gravity, and containing a large amount of urea, and sometimes albumin in small amount. The chief cause is the allowance of food too rich in nitrogenous materials, with insufficient exercise, and the affection is mostly seen when the animal is put to work after a period of idleness. (c) Hmmo-albuniimma, also known as red water — occur- ring in cattle. In this disease the urine is dark-coloured, containing albumin, and the colouring matter of the blood in a disintegrated condition. The causes are chiefly dietetic, the food being inferior in quality, result- ing in an impoverished condition of the blood. The albumin, being unfit for nutrition, is excreted by the kidneys along with a portion of the haemoglobin, which becomes broken down, giving the characteristic colour to the urine. We may also draw attention to a condition of the urine in which a large amount of phosphates are present These have a tendency to become precipitated in the mucous membrane of the bladder or urethra, giving rise to irritation, or in some instances to the formation of calcuh. The causes are also dietetic errors. Digitized by Microsoft® 180 VETERINARY THERAPEUTICS IV. Natural Recovery. If the renal disorder depends on derangement of the blood, or of other important organic functions, it is obvious that natural recovery will follow when these become changed to a normal condition. If, however, organic changes occur in the kidney, the skill of the therapeutist will be severely taxed in order to prolong vitality, in consequence of the serious results which follow and the implication of other vital organs. We must, however, recognise that the kidney possesses many provisions which tend to a natural recovery whenever this result is possible. Thus, increased work is met by increased functional activity ; also, if one kidney be diseased, the other endeavours to perform its work, a condition of compensa- ting hypertrophy occurring in the healthy organ. The condition termed vicarious compensation is also an important one. Thus, we find that the skin and the bowels endeavour to carry off the effete products which are normally excreted by the kidneys, but which are apt to be retained in renal diseases. This effort of nature is taken advantage of by the therapeutist by stimulating the bowels and skin to action by purgatives and dia- phoretics, and thus preventing the accumulation of effete materials in the system, and also giving the kidneys a temporary rest in cases where such is desirable. V. Therapeutics. Under this heading we can only draw attention to some important general principles in the treatment of renal affections. 1. The Use of Diuretics is not confined to the treat- ment of affections of the kidney, as in other disorders we find these agents of great therapeutical value. Thus, Digitized by Microsoft® THE USE OF DIURETICS 181 in cases of dropsy connected with cardiac disorder, agents such as digitalis, by acting as cardio-vascular diuretics, remove the excessive fluid, and also relieve the heart aud general circulation. Also in cases of rheumatic disorders diuretics hasten the expulsion of the morbid poison from the system. In all such instances a combination of diuretics will Le found useful, such as of the cardio-vascular with the saline, etc. In acute inflammatory affections of the kidneys, diuretics — especially those of an irritating nature — should be avoided, and the bowels and skin should be stimulated, so as to carry off the effete pro- ducts. Saline purgatives are especially useful, and their effect may be kept up by small repeated doses. In chronic affections, such as the large white kidney of Bright's disease, great discrimination is necessary in prescribing treatment, especially with reference to diuretics. From what we have already considered, it is obvious that in this affection there is constant danger of deficient excretion of urea, by reason of the epithelial cells being diseased, so that the indications are to relieve these cells by diverting the excrementitious products to other channels, and avoiding excess of nitrogenous food. Thus, hydragogue purgatives are indicated, also dia- phoretics, etc. Although renal stimulants, such as saline and special diuretics, may be considered as contra-indicated in such cases, nevertheless there are instances in which they prove useful, by clearing out the tubules when they are blocked by cellular and inflammatory products. This is accomplished by the diuresis induced. 2. Urinary Derangements depending on Nervous Dis- order. — These will be rationally treated by prescribing Digitized by Microsoft® 182 VETERINARY THERAPEUTICS remedies directed to the nervous system, depending on the nature of the affection. In diabetes insipidus, the first step in treatment will be attention to the food. Then mild aperients and the administration of iodine or iodide of potassium prove of service. In severe cases opium acts beneficially. In that affection termed diabetes mellitus, or glycosuria, which is of rare occurrence in the horse, but is met with in the dog, the pathology is obscure. It is generally believed that the liver is the chief organ involved, although the prominent symptom is a profuse secretion of urine containing glucose, with excessive thirst. The treatment will consist in avoiding starchy and saccharine articles of food and the administration of small doses of opium with mineral tonics. 3. In Renal Affections depending on Abnormal Condi- tions of the Blood it is clear that the first indication will be to bring about a return of the vital fluid to a normal condition. This will be accomplished by acting on the bowels and skin, and paying special attention to dietetics. In azoturia it is essential that the bowels be acted on by a purgative, and the skin by diaphoretics, so as to remove as expeditiously as possible the effete materials which exist in the blood, and which give rise to the characteristic and serious symptoms. If the urinary secretion be deficient, diuretics will be indicated, those being selected which have an effect on the solid portions of the urinary secretion. In ' red water ' in cattle it is of great importance to promote the action of the bowels ; but our endeavours should also be directed to restore the blood to a normal condition by the allowance of nitrogenous food and agents which have a special action on the blood, such as chlorate of potash. Digitized by Microsoft® BOD Y HE A TA ND ITS BEG ULA TIONj THE SKIN 183 In oxaluria and conditions of excess of phosphates in the urine, the bowels should be acted on, the diet attended to, and dilute mineral acids with vegetable tonics administered, such as the dilute nitro-muriatic acid, with tincture of nux vomica and gentian. CHAPTBE XIV. THE BODY HEA.T AND ITS REaULATION ; THE SKIN. I. Physiological Relations. The heat of the body is the result of changes occurring in the tissues. The largest source is the oxidizing of carbon into COj ; but many other changes occurring in the system also result in the formation of heat, such as muscular contraction, etc. The normal temperature of the body is the result of a certain amount of heat being produced, portion of which accumulates in the system, and portion of which is lost. The bulk of loss of heat is due to evaporation by the skin, the heating of inspired air, food, etc., a small pro- portion being due to radiation. The production of heat in the system varies at different periods, as also does the external temperature, so that it is necessary that some means of regulating the body tem- perature should exist. This we find is a complex and sensitive nervous mechanism, consisting of governing centres, afferent nerves from parts capable of receiving impressions, and efferent nerves carrying impressions to active organs. The Skin occupies a most important position with refer- ence to the regulation of the body temperature, and also Digitized by Microsoft® 184 VETERINARY THERAPEUTICS as an excretory organ. It contains important glands, termed sudoriparous or stveat glands, which secrete an albuminous fluid termed sweat, consisting of organic and inorganic matters of the nature of an excretion. The skin also possesses a respiratory function, CO2 being passed out and oxygen passed in ; but this process is not very active in the higher animals. The skin is highly endowed with sensory nerves, and also with bloodvessels ; it is a bad conductor of heat, this being assisted by the subcutaneous layers of fat, and also by means of the hair growing from the skin. The afferent nerves originating in the skin carry im- pressions of temperature, whether of heat or cold, to the brain and cord. These impressions are received by the cerebrum, becoming sensations of temperature, also by the sweat centres in the medulla and cord, and many other centres, such as the vaso-motor, cardiac, respira- tory, etc. The efferent impulses proceed from the sweat centres to the sudoriparous glands, either stimulating or depress- ing them, according to their nature. They also proceed from the other centres, producing effects on the cu- taneous circulation, the general circulation, the renal secretion, etc. The sudoriparous glands of the horse are not easily acted on by drugs ; and, according to Professor Smith, we possess no drug which can excite the secretion of sweat in the horse ; he has proved by experiment that pilocarpine has no effect on the sweat-glands of this animal, although it produces a profuse salivary flow. Cattle possess very rudimentary sweat-glands, not easily acted on. They are believed to perspire princi- pally in the muzzle ; while in the dog the skin practically does not sweat, except in the foot-pads. In this animal Digitized by Microsoft® BODY HEAT AND ITS REGULATION ; TEE SKIN 185 the respiratory passages are supposed to assist in this function, and also in the regulation of the body tempera- ture, exemplified by the panting observed in hot weather and after exercise. In connection with the temperature of the surround- ings of aniinals we have to draw attention to the effects produced when this is either raised or lowered. (a) If the Temperature be raised, the regulating nervous mechanism is called into action, and the following effects occur : 1. Increased loss of heat by the evaporation of the perspiration, by the cooling of the blood in the dilated cutaneous vessels, and also in the lungs. 2. Diminished 'prodiwtion of heat in the muscles, glands, etc. In muscular exercise there is increased metabolic activity, causing a rise in the internal tem- perature, the cutaneous vessels are dilated, perspiration occurs, respiration and circulation are increased, and the activity of metabolic organs, such as the liver, is tem- porarily lowered. (&) If the Temperature be lowered, two effects are pro- duced in a reflex manner through the medium of the nervous system : 1. Diminished loss of heat, due to contraction of cutaneous vessels, arrest of perspiration, and reduced activity of circulation and respiration. 2. Increased production of heat in internal organs, especially the muscular, digestive, and circulatory. II. Pharmaco-dynamics. Under this heading we will refer to the power we possess over the regulation of the body heat and the skin. Digitized by Microsoft® 186 VETERINARY THERAPEUTICS 1. By Means of acting on the Cutaneous Circulation. — These comprise a power of withdrawing heat from the body by modifying the amount of blood and the rate of flow in the cutaneous vessels. {a) The blood can be cooled by causing dilatation of these vessels, accomplished by increasing the surrounding temperature, also by the use of the hot bath, and by the administration of diffusible stimulants, such as alcohol, spirits of nitrous ether, etc. (&) Similar effects are produced by increasing the flow of blood through the cutaneous vessels, accomplished by cardiac stimulants of all kinds. 2. By acting on the Sweat-G-lands by Agents termed 'Diaphoretics' or 'Sudoriflcs.' — These increase the amount of perspiration, and include a variety of means and agents acting in different ways : (a) By stimulating the ajferent cutaneous nerves by means of the surrounding temperature being raised, as in the Turkish bath, also by means of warm clothing, and stimulants, such as moderate doses of alcohol, etc. (b) By acting on other afferent nerves which stimulate the sweat-glands refiexly, such as by aromatic drinks, which act on the nerves of the mouth, throat, and stomach. (o) By acting on the sweat centre in the medulla directly. These include narcotics which produce this effect by increasing the venous condition of the blood, such as opium, chloroform, etc., also by measures which increase the flow of blood through the centre, such as hot drinks, etc. {d) By stimulating the terminations of the nerves in the siveat-glands, and also the secreting cells of these glands, such as by pilocarpine, which produces profuse and rapid diaphoresis ; also by dilating the vessels, and thus in- creasing the flow of blood to the glands. Digitized by Microsoft® DIAPHORETICS AND ANHYDROTICS 187 Some agents, such as acetate of ammonia, cause diaphoresis in a complex manner. This agent is sup- posed to both stimulate the secreting cells and to be excreted from them along with an increased amount of water. Other drugs acting in a manner not perfectly clear are camphor and also ipecacuanha in the form of Dover's powder. We find that some diaphoretics act in more ways than one ; thus, alcohol dilates the cutaneous vessels, increases the rate of blood-flow, and stimulates the afferent nerves and sweat centres. We may here notice a group of agents which have an opposite effect to diaphoretics ; these are termed anhy- drotics. These diminish the amount of perspiration, and they produce this effect by acting in different ways : (a) By depressing the sweat centre, acting indirectly by stimulating the cardiac and respiratory centres, and thus overcoming the venous condition of the blood, which in weakness and exhausting diseases frequently produces sweating of that peculiar nature termed cold sweatwig. Examples. — Alcohol, ammonia; nerve tonics, such as strychnine, iron, etc. ; while proper attention to food, air, etc., cannot be overlooked as auxiliaries. (6) By depressing the terminations of the secretory nerves of the siveat-glands. Examples. — Belladonna and its alkaloid, atropine, hyoscyamus and its alkaloid, hyoscyamine. These agents have a very marked effect in diminishing or checking excess of perspiration. 3. We can act on other Excretory Organs for the purpose of reducing the Heat of the Body. — Purgatives and diuretics cause a direct loss of heat by abstracting an increased amount of warm excretions from the body, through the medium of the bowels and kidneys. This Digitized by Microsoft® 188 VETERINARY THERAPEUTICS effect is assisted in the case of purgatives by the reflex dilatation of cutaneous vessels which accompanies pur- gation ; but we shall find that in most febrile conditions which we have to treat, strong purgatives will be contra- indicated, although laxatives will be of great service. 4. We can act on the Heat-forming Tissues in the body by the use of certain drugs which possess the power of diminishing tissue change. Such agents are termed antijiyretics, and are represented by quinine, salicylic acid, antipyrin, etc. These interfere with metabolism, and lessen the amount of heat formed, by reducing the activity of the tissues ; they have little effect on healthy animals, this being attributed to the normal mechanism of regulation of temperature. Other drugs, such as alcohol, reduce temperature by diminishing tissue waste, but do so in a different manner from quinine. Alcohol becomes oxidized in the tissues, thus sparing them to some extent ; and although generating a certain amount of heat, its action in the circulation is such that a dimi- nution of temperature is the total result. Other drugs, such as aconite, probably reduce tempera- ture by their effects on the circulation. III. Pathological Eelations. As we have already shown that the normal temperature of the body is the balance between the production and the loss of heat, both of which are under the control of the nervous system, we have now to consider the effects of disturbance or disorder of these relations, leading to that abnormal condition of the system termed pyrexia, or fever. The chief characteristic in fever is elevation of the body temperature ; but there are many concomitant phenomena which also require consideration, consisting of derangement of vital functions and a condition of Digitized by Microsoft® PYREXIA 189 general depression. Briefly speaking, the following may be taken as the most common causes of the condition of pyrexia : 1. Interference with the Refrigerating Function of the Skin. — This is generally due to the effect of exposure to cold, or sudden changes of the temperature of the sur- roundings, producing what is popularly known as a chill. The impression of cold on the afferent nerves leads to interference with the nervous mechanism pre- siding over temperature, the cutaneous vessels become contracted, the perspiration arrested, rigors or shivering fits occur, and heat being thus retained in the system causes elevation of the temperature. 2. In those febrile affections which we believe to depend on the presence of specific organisms in the system, or to be associated with them, we have good grounds for stating that the life of such organisms, the processes of fermentation associated with them, and the destruction of tissues produced by them, are all factors in causing elevation of temperature. 3. Pyrexia may depend on a combination of the causes mentioned ; for example, in the case of a wound in which pus may become decomposed and be absorbed, a general systemic disturbance occurs, the skin, lungs, and circulation become disordered, and temperature is raised. The Increased Production of Heat in Fever depends on increased activity of metabolism, which fact is proved by the rapid emaciation, by the increased a.mount of the products of oxidation of tissues, viz., urea and other excretions. The following conditions also occur in fever, along with the elevation of temperature : The Skin in the first stages is hot and dry ; if the fever be ushered in by a chill or rigor the cutaneous vessels Digitized by Microsoft® 190 VETERINARY THERAPEUTICS are contracted, and the surface of the body is cold, especially the extremities. The Nervous System is depressed, but in some instances restlessness and delirium may be present ; these, how- ever, are not often met with in our patients as compared with man. The Pulse becomes altered in character, and the respi- rations accelerated, depending on the degree of the rise of temperature, and on the organs involved in the affec- tion of which the fever is an accompanying condition. The Digestive System becomes disordered, evidenced by dryness of the mouth, thirst, loss of appetite, and constipation of the bowels. The Urinary Secretion is scanty, highTcoloured, and its solid constituents are both relatively and absolutely increased. Nutrition is interfered with, shown by general emacia- tion, the degree of which depends on the intensity and duration of the febrile affection. We must regard fever as one of the prominent symptoms found in those affections which are usually accompanied by it, rather than as a distinct condition. There is, however, a form of fever met with termed febricula, or sifnple fever, which appears to arise inde- pendent of serious complications, and tends to a quick recovery. We have already alluded to this form in Part I, p. 20. The occurrence of fever often precedes the advent of the special changes in organs induced by the various diseases ; at least, those changes which we can detect by an examination of the patient and an observation of the symptoms. We regard the recognition of fever as a very important item in therapeutics ; although we may not immediately Digitized by Microsoft® PYREXIA 191 be able to determine the exact nature of the disease which is likely to follow, still, we can adopt treatment which will be beneficial in the early stages. The height of temperature is of importance during the course of a febrile affection ; but although a high temperature is a very serious condition, still, we must take into considera- tion the state of the vital organs of the body at the same time in estimating the dangers of a febrile attack. The state of the pulse, of the respirations, of the nervous and digestive systems, must be taken into account. The depressant effect of the high temperature will greatly depend on the previous condition of the organ which is invaded by the disease — whether it is weakened by the effects of previous disease or not ; and also the influence of the surroundings, whether hygienic or other- wise, must not be lost sight of. Thus, if a horse suffering from an attack of pneumonia, although showing a high temperature, has a fair appetite and a pulse not likely to cause alarm, and if in addition we are able to place him in hygienic surroundings and have him properly nursed, we would be far more confident of his recovery than in a case where, although the temperature is lower, we find the pulse is frequent, small, and compressible, the appetite poor, and the surroundings unhygienic. We have to notice a variety of fever termed inflam- matory fever, in which the rise of temperature follows the inflammatory action in parts or organs, and is thus said to be secondary. We find this condition occurring ia surgical practice, and in affections of abdominal organs, such as enteritis, peritonitis, etc. The intensity of the fever will be modified according to the nature of the parts involved by the inflammatory action at the com- mencement, and we find that the fever is not always proportional to. the size or importance of the part in- Digitized by Microsoft® 192 VETERINARY THERAPEUTICS flamed. In traumatic peritonitis, a leading symptom in addition to the fever and the pain is a small thready pulse, an effect of the great depression which exists, which quickly tends to death from failure of the heart's action. Another form of fever is termed chronic fever, in which a constant rise of temperature exists. It is met with in cases of specific diseases, such as tuberculosis and chronic glanders, and in the latter disease is a symptom of great importance as an aid to diagnosis. Disorders of Perspiration. — These we may refer to two classes, viz. : (1) Excessive siueating ; (2) deficient siveat- ing. We find excessive sweating to occur in such cases as azoturia, etc. Horses out of condition from various causes are likely to sweat excessively, even when at moderate exercise. Severe pain also causes profuse per- spiration. Deficient sweating occurs at the beginning of most . febrile affections, the skin being dry ; it also occurs in some diseases and disorders of the urinary functions. IV. Natural Recovery. In disorders of the body heat, as well as in the phenomena which accompany them, there is a natural tendency to return to the normal, and the aim of the therapeutist should be to assist nature as much as possible, and avoid undue interference. Febrile affections generally run a definite course, and cannot be cut short by any line of treatment ; so that attention to the vital functions, and careful nursing and hygienic surroundings, form the chief details of rational treatment, in connection with the use of agents to reduce the pyrexia. Digitized by Microsoft® TREATMENT OF PYREXIA 193 v. Therapeutics. It is clear that remedies can only rarely reach the actual cause of febrile disorders, so that our treatment will be chiefly symptomatic. 1. In cases depending on interference with the functions of the skin in regulating body temperature, the indications are to increase the cutaneous circulation, and to gently stimulate the secretions of the body. For these purposes we prescribe diaphoretics, and apply suitable clothing. Agents thus employed are liq. ammonii acetatis, spiritus aetheris nitrosi, and moderate doses of alcoholic stimu- lants in case of the occurrence of rigors. 2. In cases of high temperature depending on general increase of metabolism, agents such as quinine, salicin, phenol derivatives, etc., are indicated. In eases which we believe to depend on the presence of micro-organisms in the system, we employ disinfectant antipyretics in order to destroy, if possible, these organisms and their life processes. Such agents are represented by quinine, salicin, etc. 3. It is clear that as fever may depend on a combina- tion of causes, so our treatment of it must vary according to circumstances, and a combination of agents may be desirable. It is important that the functions of the skin, kidneys, bowels, etc., be kept regular, taking care, how- ever, to avoid any measures likely to depress the patient. If the heart be weak, indicated by the condition of the pulse, stimulants will be required, of which alcohol will in many instances be found a most useful agent. It stimulates the cutaneous circulation and the sweat- glands ; it spares tissue waste, acts as a food to the system, besides acting as a cardiac stimulant and an antiseptic antipyretic. But, like all other medicinal 13 Digitized by Microsoft® 194 VETERINARY THERAPEUTICS agents, it requires to be used with caution and judgment, in properly regulated doses, and in suitable eases. The kidneys and bowels are kept regular by the allowance of salines in the drinking water, such as sulphate of magnesia with nitrate of potash. In cases where the temperature runs high, the use of quinine will be indicated, a large dose being given at first, followed by smaller quantities as required. In cases depending on traumatic causes, abdominal affections, etc., anodynes to relieve the pain must be administered along with febrifuges, and other means adopted as the special demands of the cases require. Disorders of Perspiration are treated according to their nature and causes. The excessive sweating which is found in many cases of azoturia is evidently an effort of nature to remove the excess of deleterious materials from the system, and is to be encouraged by diaphoretics and warm clothing. In cases where horses sweat on the slightest exertion, nervine tonics are indicated, with strict attention to hygiene and dietetics. Anliydrotics, the most powerful of which are belladonna and hyoscyamus, may be indicated. Briefly speaking, these may act by diminishing the activity of the sweat- glands, also by lessening the excitability of the sweat centres, or by acting on the circulation and stimulating the respiratory centre, and in this way overcoming that venous condition of the blood which is apt to occur in cases of debility, and which is a cause of the abnormal sweating accompanying such a condition of the system. Digitized by Microsoft® THERAPEUTICS OF THE SURFACE OF BODY 195 CHAPTEE XV. THE THERAPEUTICS OF THE SURFACE OF THE BODY. From our knowledge of the physiological relations of the surface of the body, we can easily appreciate the import- ance of this portion of our subject to the therapeutist. The skin is highly endowed with sensitive nerves, and is also very vascular, so that it is very susceptible to external influences, not only those acting on it through the medium of the surrounding temperature, but also those which we can apply for certain therapeutical pur- poses. By acting on the surface of the body we can produce effects on distant parts, such as the nerve centres, the general circulation, and even the entire system. Such effects are produced by means of the nerves, which have extensive relations throughout the system, and also by the cutaneous vessels. We must remark, however, that the modus opermidi of the measures which we adopt is by no means so simple as might be imagined, as in many instances it will be found to be complex as well as obscure. I. Pharmaco-dynamics. The measures which we adopt may be conveniently considered under the following heads : 1. Counter-irritants. 2. Baths and Allied Measures. 3. Surgical Applications. Counter-irritants are those agents which when applied to the skin cause either stimulation or inflammation of it, Digitized by Microsoft® 196 VETERINARY THERAPEUTICS depending on the strength of the appHeation. By reflex action they also produce effects on remote parts. Counter-irritants are arranged according to the degree of their action into the following classes : (a) Bubefacients produce a degree of redness and con- gestion of the skin. The alteration in colour of the skin is not always visible in veterinary patients. These agents are represented by hot water, mustard applied in modera- tion, solutions of ammonia, volatile oils, such as camphor, turpentine, etc. (6) Vesicants or Epispastics. — These are more active agents ; they cause at first reddening of the skin, with increased heat, and a sensation of smarting. In a variable time, depending on the strength of the applica- tion, the papillae of the skin become raised and vesicles form ; these enlarge and coalesce, forming blisters of various sizes ; they contain an albuminous fluid, and generally fibrin. After a. variable time they either dry up or a muco-purulent fluid is exuded, which becomes hard, forming a scaly covering to the part ; this gradually falls off as new skin becomes formed. Examples. — Cantharides, strong applications of mus- tard, boiling water. (c) Suppurants or Pustulants. — These cause inflamma- tion of the deep-seated portions of the skin, and the formation of pustules. They are represented by bin- iodide of mercury, croton-oil, tartar emetic, etc. Vesicants applied very strong and repeatedly have a similar effect. There are other forms of counter-irritants besides the medicinal agents mentioned, such as the actual cautery and setons. The General Action of Counter-irritants. — It will be readily seen that the general action of counter-irritants is a very complex one, although the measures adopted are simple in their application. Digitized by Microsoft® THEORY OF COUNTER-IRJRITATION 197 In order to understand the theory of the therapeutical value of these agents, it is essential that we study care- fully not only their local actions, but also their effects on the different portions of the vital system. For the purpose of description we may divide the action of a counter-irritant into three stages : 1. The effect on the skin is stimulant ; the cutaneous vessels become dilated by a direct action on their nerves, and the local circulation becomes more free, the sensory nerves are irritated, and pain is produced of a smarting character. The effect on the general system is that of a stimulant, this being accomplished by reflex action. There is a similar effect produced on the individual organ over which the counter-irritant is employed. Eeflexly the heart's action is accelerated, the blood-pressure raised, respira- tion is quickened, and the cutaneous vessels become con- tracted. The painful impression rouses the higher nerve centres. After a certain period the cutaneous nerves become depressed, and pain subsides. 2. If the application of the counter-irritant be pro- longed, the second stage is reached, viz., that of vesica- tion. Local pain is now induced, and if the process be extensive, there is depression and innervation of vital organs, the amount of serum withdrawn from the vessels being an important factor in the production of these effects. 3. If the degree of counter-irritation be still more severe, pustules are formed, and the remote effects are greater than in the stage of vesication. The Theory of Counter-irritation in Therapeutics. — Perhaps in the whole range of therapeutics there is not more difference of opinion existing, not only as to the modus operandi of counter-irritants in the treatment of Digitized by Microsoft® 198 VETERINARY THERAPEUTICS the affections for which they are recommended, but their beneficial action is questioned altogether by competent authorities. We need only refer to standard works on veterinary medicine, and also to professional literature, to become aware that while one authority definitely states as the result of actual experience that counter-irritation is of signal benefit in the treatment of pulmonary affec- tions, another authority, quite as eminent, condemns the practice as not only useless but harmful to the patients. Those who believe in the beneficial effects of counter- irritants to the walls of the chest in cases of pneumonia, pleurisy, or bronchitis, base their views on the following actions which these agents are capable of producing : (a) That by acting on the skin over the region of a part or organ, we can produce certain effects on the nutrition of the latter, as well as the functions. (6) That by this power we can influence internal morbid processes by creating external irritations. These are based on the idea that we possess influence over : 1. The circulation of parts in immediate vascular con- nection with the area of skin irritated. By means of rubefacients and vesicants it is believed that the circulation will be attracted to the area of skin, that the plasma will be drained off, and thus internal congestions or inflammations will be diminished. This is also explained by the fact that, in congestion of the brain or of its coverings, the administration of a drastic cathartic proves beneficial by diverting the blood to the intestinal canal, and thus affording relief to the affected organ. 2. It is believed that we can influence deep-seated parts by irritating the cutaneous nerves, which, acting in a reflex manner through the centres in the brain and Digitized by Microsoft® THEORY OF COUNTER-IRRITATION 199 cord, will modify the circulation and nutrition of the parts beneath the area to which the counter-irritant is applied. 3. By counter-irritation we can affect the trophic and vaso-motor centres in the brain and cord, which preside over the area of skin irritated ; and in a reflex manner a neighbouring trophic centre may be influenced, which will induce a change in the nutrition of the tissues in the neighbourhood of the irritated area of skin. As examples of pathological conditions explaining these phenomena, the following are quoted by Dr. Wood : ' The formation of a duodenal ulcer as the result of a burn of the skin, especially of the abdominal wall. Sympathetic ophthalmia, caused by the presence of a diseased tooth.' The above illustrate some of the views held as to the theory of counter-irritation.* We have now to inquire as to the pathological conditions in which counter-irritants are indicated and prove of benefit. We find most autho- rities agreeing as to their beneficial action in cases of subacute or chronic inflammations of joints, tendons, etc., also in cases of rheumatism affecting different por- tions of the body, in phlebitis, and other diseased condi- tions. But when we come to consider the question of the value of counter-irritation in thoracic affections, we find the most striking differences of opinion to exist among authorities. Those who are in favour of counter- irritation state, as the result of considerable experience, that they have found morbid conditions of the lungs and thoracic organs benefited by moderate vesication applied to the chest-walls. They note favourable results in from twelve to twenty-four hours, consisting in an improve- ment in the pulse, temperature, and respiration. On * For further information on this subject, see ' Therapeutics and Materia Medica,' by Dr. H. 0. Wood, p. 475, Digitized by Microsoft® 200 VETERINARY THERAPEUTICS the other hand, we find authorities who are opposed to counter-irritation bringing forward strong evidence that the practice in such cases is not only useless, but actually productive of harm to the patient, raising the tempera- ture, causing restlessness, and increasing instead of modifying the morbid processes in the organs involved by the disease. Without adhering to either of these opinions, we may safely state, as the result of clinical experience, that the indiscriminate use of strong counter-irritants to the chest-walls in cases of thoracic affections is both irra- tional and harmful in practice. A moderate amount of counter-irritation is of the greatest benefit in some cases, while in others it can be entirely dispensed with. Hot applications to the chest-walls we have found of great service, but when improperly applied, they are productive of more harm than good, and hence the application of a moderate counter-irritant must always have the prefer- ence where the satisfactory adoption of the other measure is impossible. No hard and fast rule can be laid down as to the employment of counter-irritation or otherwise, but this fact we must "lay stress on, that it is clearly wrong practice to apply severe and prolonged irritation to the thoracic walls, causing extensive and deep-seated struc- tural changes in the skin, with the hope of relieving the diseased process in internal organs. In the primary stages of thoracic affections, where a high temperature is a prominent symptom, and if, in addition, the animal is excitable, it would be clearly irrational to apply counter-irritants where rest, pure air, and attention to the diet, with simple medicinal agents, will of themselves bring about a return to the normal state. But there are cases where counter - irritation Digitized by Microsoft® USES OF COUNTER-IRRITANTS 201 proves of great benefit, when it is properly and carefully carried out. In cases of acute congestion of the lungs we have seen the most favourable results from the application of moderate stimulation to the thoracic walls, in conjunc- tion with other important details of treatment. Again, there are instances in the course of pulmonary affections where the usual treatment is not attended with that change in the condition of the patient which we are anxiously watching for. In popular language, the case is ' hanging fire,' and we find the application of a moderate counter-irritant to the thoracic walls to be productive of very satisfactory results. Among other diseased condi- tions where counter-irritation is of signal benefit we may mention eases of laryngitis, pharyngitis, etc. ; also in cases of strangles, by causing the maturation of the sub- maxillary abscess. We find that although the beneficial effects of counter- irritation are generally admitted in oases of chronic lameness depending on affections of bones, cartilage, tendons, or ligaments, still there is great difference of opinion existing as to the manner in which these results are brought about. Experiments by authorities have given totally different results, the main point at issue being whether the inflammatory action produced by the counter-irritant extends below the skin and subcutaneous tissues, or otherwise. The bulk of evidence would go to demonstrate that the beneficial effects produced in such cases are due to the counter-irritant exciting a process of reparative inflammation in the diseased parts, which overcomes the original diseased process, or, in other words, assists nature in the process of repair. Take the case of a horse lame from bone spavin, which has resisted the usual treatment by line firing and Digitized by Microsoft® 202 VETERINARY THERAPEUTICS blistering. Now, if when the part has been deeply fired with a sharp-pointed iron, and when a long rest has been allowed, the animal goes sound, surely we are not going to believe that the inflammatory process induced did not extend beyond the skin and subcutaneous tissues. We are fully aware that in performing the operation we pierce the exostosis with the cautery, and we are justified in concluding that the beneficial results produced were due to the reparative process set up, which assisted nature to cause anchylosis of the opposing surfaces of the diseased bones, and thus removed the pain and lameness, and as an auxiliary to which we must regard rest as very im- portant. 2. Baths and Allied Measures. — In veterinary practice we do not make use of baths, either hot or cold, to the same extent as in human medicine. The large extent of the skin of horses and cattle, and the difficulty in over- coming the evil effects of excessive reactions, are among the circumstances which prevent the general adoption of baths. Hot baths are of the greatest benefit in canine practice, and are employed for a variety of diseased con- ditions. Great care is, however, necessary in order to avoid the injurious effects of reaction, and to guard against the danger of chills, etc. The patients should be carefully dried, and kept in kennels maintained at a proper temperature. The Turkish Bath, as a therapeutic agent, is one of great value and importance, and no veterinary infirmary is complete without a properly fitted bath of this kind. In cases of chills, rheumatism, laminitis, renal affections, etc. , the Turkish bath is of benefit in the early stages ; but we must be careful not to cause excessive reaction, and also to see that the animal is properly clothed, and Digitized by Microsoft® FOMENTATIONS AND POULTICES 203 not afterwards exposed to cold. We may also refer to the value of the Turkish bath in affections of the skin extending over a wide area, whether in horses or dogs, The action of the hot air softens the cuticle, and enables applications to have the desired effect. The Effects of Gold and Hot Applications. — The effect of the application of cold to a part for a time is to cause contraction of the afferent arteries by reflex action, and, as a result, the amount of blood going to the part is lessened. Heat dilates the capillaries, reduces tension and relaxes tissues, soothes the nerves of the part, and thus relieves pain. Fomentations are composed of hot water, either medi- cated or otherwise. They are applied to inflamed parts for the purpose of lessening tension and pain, and require care in their use, so as to avoid the effects of reaction. Their application should be continued for a considerable time, with water at the required temperature ; the parts should be well clothed afterwards, and a stimulating liniment applied, so as to prevent chilling. Poultices are applications composed of substances such as linseed-meal, bran, oatmeal, boiled carrots or turnips, spent hops, etc. Their uses are various in cases where heat and moisture are beneficial either in soothing the nerve endings in inflamed parts, or in favouring the ma- turation of abscesses. In cases of punctured wounds of the feet in horses, after the judicious use of the knife to provide proper drainage, poultices are very useful. It is necessary to remark, however, that poultices require to be employed with discretion, so as to avoid their use in the case of wounds where we may, by dry antiseptic dressings, induce more favourable results. They should not be continued for too long a period, as they are apt to produce a softened, unhealthy condition of the part Digitized by Microsoft® 204 VETERINARY THERAPEUTICS and excessive granulations, which interfere materially with the reparative process. In many instances it is necessary to medicate poultices ; thus, in wounds of the feet associated with much pain, local anodynes, such as belladonna, are very useful. In every case we should endeavour to render poultices applied to open surfaces antiseptic by the addition of agents, such as carbolic acid, creolin, etc., in proper proportions. It is also necessary to remember that poultices should be changed at least twice a day, to avoid putrefactive changes. When wounds become greatly inflamed, and great pain and irritability exist, the beneficial effects of poultices judiciously applied are beyond question. The selection of either hot or cold applications for therapeutical purposes is very often a question of taste, and depends much on the nature of the case. As a rule, we may state that where pain and tension are prominent symptoms the use of heat is indicated ; this acts beneficially by soothing the peripheral nerve-endings, relieving the tension of the vessels, and softening the skin. There are many instances, especially of unhealthy conditions of the joints, ligaments, and tendons of horses, where the application of cold, such as that produced by a continuous stream of cold water over the parts, is pro- ductive of great benefit. As examples, we may mention cases where it is necessary to reduce existing heat or inflammation prior to the application of a counter- irritant ; also in cases of open joint the continued application of cold relieves the pain, and checks the inflammation in the synovial membrane. 3. Surgical Applications. — These properly belong to the domain of surgery, so that only a brief mention can be made here of the therapeutical agents employed in Digitized by Microsoft® SURGICAL APPLICATIONS 205 this respect; these agents will, however, receive atten- tion under their respective heads in Part III. (1) Antiseptics. — These agents either prevent the en- trance of organisms into a wound or destroy them, and arrest the processes giving rise to fermentation and decomposition. They are represented by carbolic acid, creolin, boracic acid, iodoform, perchloride of mercury, etc. (2) Disinfectants are for the most part similar materials to antiseptics, but are employed in a much stronger form, and are also used for the purposes of preventing the spread of infectious and contagious diseases. They destroy micro-organisms and their products, and are employed in cases of putrid wounds, etc. They are represented by strong solutions of carbolic acid, chloride of zinc, chloride of lime, sulphurous acid, etc. (3) Deodorants. — These possess the power of absorbing gases and neutralizing foul odours, and are represented by charcoal, solutions of permanganate of potash, etc. (4) Astringents coagulate or precipitate albuminous discharges, and contract or constringe the vessels of a part, thus limiting the process of exudation. For surgical purposes they are employed to lessen excessive discharges, and to check granulations, thus imparting tone to wounds. They are represented by solutions of the acetate and subacetate of lead, sulphate of zinc, alum, etc. (5) Stimulants are employed in surgical therapeutics to check excessive granulations in a wound, and to hasten the healing process when this is tardy. They are represented by mild applications of a caustic, such as nitrate of silver. (6) Styptics are agents employed for the purpose of arresting hsemorrhage from injured vessels or surfaces, either the result of accident or from surgical wounds. Digitized by Microsoft® 206 VETERINARY THERAPEUTICS They are astringents, and act either by coagulating albumin, and thus plugging the bleeding vessels, or they cause contraction of capillary vessels. Styptics are represented by persalts of iron, benzoin, tannic acid, acetate of lead, hazeline, etc. Pressure, such as with tow or lint, acts as a mechanical styptic. (7) Caustics and Escharotics. — Caustics possess the power of destroying living tissue with which they come in contact. They combine with the water and albumin of the tissues, and when they produce an extensive slough are termed escharotics. Caustics are employed for destroying virus in wounds, for removing warts and unhealthy growths, and for promoting the healing pro- cess in sinuses and fistulas. They are useful in sup- pressing exuberant granulations and in hastening the healing process when this is slow, probably by stimu- lating the trophic nerves and the capillary vessels of the part. (8) Vesicants are sometimes employed in cases of ulcerating surfaces which tend to become chronic, and are difficult to heal. They stimulate the local circula- tion, and promote the reparative process, cantharides being the agent usually employed for this purpose. (9) Anodyfies are employed in cases of wounds charac- terized by persistent pain and irritation. They are applied locally as well as administered internally, the prepara- tions of opium and belladonna being most useful in this respect. Before concluding the subject of general therapeutics, we may refer to the actions of msdicinal agents on the eye. Local anesthesia of the eye is produced by the applica- tion of a solution of cocaine. Digitized by Microsoft® MYDRIA TICS AND MYOTICS 207 The wis is dilated by belladonna and its alkaloids, also by hyoscyamus, etc. ; such agents are termed mydjiatics, and produce their effect whether applied locally or given internally in sufficient amount. The iris is contracted by Calabar bean and its alkaloid, physostigmine, by opium, pilocarpine, etc. ; such agents are termed myotics. Digitized by Microsoft® PART III. SPECIAL THERAPEUTICS. CHAPTEE I. INTRODUCTORY. We have now to consider the actions of the various medicinal agents, and their uses, founded on our know- ledge of their actions. New remedies are ever on the increase, and as our knowledge of pathology advances, so will our efforts to discover new means to combat disease be continued. As a rule, new remedies or methods of treatment, when first brought forward, are eagerly sought after. Some stand the test of practical usefulness ; others, after a brief existence, are ignored because they have not acted up to the expectations of their introducers. The number of drugs employed for therapeutical purposes is very large, but it is clear that there are many which from want of precise knowledge concerning their actions, and of clinical data concerning their therapeutical value, cannot be accorded more than a passing notice in a work of this kind. There are certain drugs which have been proved by both experimental and clinical evidence to be of definite therapeutical value, and these of necessity will require a more detailed consideration at our hands. Digitized by Microsoft® SPECIAL THERAPEUTlCfi 209 As previously remarked, we must not be too hasty in according all beneficial results in our treatment to the action of the drugs employed, seeing that, in the majority of instances, rational treatment consists in aiding the efforts of nature to overcome the diseased condition existing in our patients. In the treatment of a case we must keep this point clearly in view, so as to have a proper perception of what we expect the medicinal agents employed to bring about. A combination of different drugs, with a vague notion of what their result in the system of the patient shall be, is irrational both in theory and in practice. The effects of a drug must be carefully watched during the course of an affection, remembering that patients are not alike susceptible to its actions. Of course the preference for special drugs in certain affections, by different practitioners, is due to the fact that they have obtained beneficial results from their use, and it is only natural to expect that, when a line of treatment proves successful, the practitioner is likely to continue it in cases of a similar character. Nevertheless we must admit that a departure from the beaten track is often of benefit, and it is rational to believe that in the future the science of pharmacology will advance and change as our knowledge of pathology extends. In the classification of drugs various methods are adopted. Some authors arrange the medicinal agents in alphabetical order. Others classify them according to their actions, but as many drugs are entitled to be placed under different headings by reason of possessing more actions than one, this plan is not a satisfactory one. The plan which we shall follow is that adopted by Dr. Mitchell Bruce in his work on ' Materia Medica and 14 Digitized by Microsoft® 210 VETERINARY THERAPEUTICS Therapeutics.' It consists in arranging the drugs ac- cording to their natural order — that is, according to their source, whether derived from inorganic or from organic materials. By subdividing these we can group together many medicinal agents possessing similar actions, and thus conveniently compare these actions when necessary. The following is the sketch of the plan to be adopted : Part I. — The Inorganic Materia Medica. Gboup I. — Alkalies and Alkaline Earths. Group II.— The Metals. Group III. — The Non-Metallic Elements. Geoup IV. — Acids. Group V. — Water. Group VI. — The Carbon Compounds. Part II. — The Organic Materia Medica. Group I. — The Vegetable Kingdom. Group II. — The Animal Kingdom. We have previously drawn attention in Part I., under the heading of the Actions of Medicines, to a convenient method of tracing the actions of a drug in the system, and whenever possible this plan will be followed. It consists in arranging the actions under four distinct heads — that is, supposing the drug to be administered by the mouth : (1.) The Immediate Local Action. (2.) The Action in or on the Blood. (3.) The Specific Action. (4.) The Bemote Local Action. Having followed the drug in its course through the system and noted its actions therein, we can then con- Digitized by Microsoft® SPECIAL THERAPEUTICS 211 sider its medicinal uses, founded on a knowledge of these actions, and also note any contra-indications to its em- ployment. There does not exist as yet any recognised Veterinary Pharmacopceia, so that in the following chapters the preparations of the agents described are those of the British Pharmacopceia, unless when for special pur- poses stronger preparations than those of the latter are mentioned. Preparations. — The majority of the agents of the Materia Mediea possess such characters in the crude state that it is necessary to prepare them for administra- tion. The following are the chief kinds of preparations in use : AcLUse (Waters) are very weak simple solutions of volatile oils in distilled water. Decocta (Decoctions) are made by boiling vegetable substances in water, straining, and adding more water. Infusions are solutions prepared by digesting vegetable substances in water. Essentise (Essences) are solutions of volatile oils in four parts of rectified spirit ; they are ten times the strength of spirits (spiritus). Extracta (Extracts) are obtained by evaporating either the expressed juice of fresh plants or the soluble con- stituents of dried drugs. Green extracts are prepared from fresh plants. Alcoholic extracts are prepared by the action of rectified spirit or proof spirit on dry drugs, and then evaporat- ing. Liquid extracts are prepared by macerating the drug in water, evaporating, and adding spirit to prevent decomposition. Digitized by Microsoft® 212 VETERINARY TRERAPEOTICS Grlycerina (Glycerines) are solutions of substances in glycerine. Pulveres (Powders) are prepared by reducing drugs by trituration to a state of fine division. Spiritus (Spirits) are solutions of colourless substances or oils in rectified spirit. They are termed Complex when prepared in a special manner, e.g., Spiritus eetheris nitrosi. Syrupi (Syrups) are fluid preparations, containing a large proportion of sugar. Tincturse are solutions of active substances in spirit, either alone or combined with other solvents. Vina (Wines) are solutions of drugs in sherry, such as vinum ipecacuanhse, or in orange wine, e.g., Vinum quinise. Misturae (Mixtures) are made by dissolving various substances in water. They are frequently compound. Linimenta (Liniments or Embrocations) are prepara- tions for external application, by friction, anointing, or painting. Lotiones (Lotions or Washes) are solutions or mixtures for external use by washing or applying in lint. Unguenta (Ointments) are mixtures of active sub- stances with lard, vaseline, lanoline, etc. Alkaloids are active principles, found in various plants, probably resulting from the metamorphosis of the albu- minoid constituents ; they are alkaline in reaction, form- ing salts with acids, and in form they are usually crystal- line solids. All contain nitrogen, and they may be regarded as compounds of ammonia. Some plants con- tain a number of alkaloids which may differ in their actions from one another, but chemical analysis affords little or no indication of such difference. For example, among the alkaloids of opium we find Digitized by Microsoft® ALKALOIDS AND ACTIVE PRINCIPLES 213 the anodyne morphine and the emetic apomorphine, the difference between the chemical formulae being only two atoms of hydrogen. Alkaloids have the terminal ' ine ' or ' ina,' and in the older works the terminal ' ia ' is given. Examples. — Morphine, atropine, quinine, cocaine, physostigmine, pilocarpine. Neutral Organic Principles are concentrated active agents, also derived from vegetable drugs. They contain carbon, hydrogen and oxygen, and occur sometimes as bases, sometimes as acids. They are distinguished from the alkaloids by having the terminal ' in,' and are represented by aloin, digitalin, santonin, salicin. Digitized by Microsoft® 214 VETERINARY THERAPEUTICS CHAPTEE II. I.— THE INORGANIC MATERIA MEDICA. GROUP I.— ALKALIES AND ALKALINE EARTHS. Of these the most important are: 1. Potassium; 2. Sodium; 3. Ammonium; 4. Calcium; 5. Magnesium. General Ebmaeks on Alkalies. — Alkalies possess the power of dissolving the nitrogenous constituents of animal tissues. This solvent power is in proportion to, yet distinct from, their affinity for water. The caustic alkalies, having a great affinity for v^ater, possess a more destructive action on the tissues than the other members of this group. On the Stomach. — Alkalies given before feeding in- crease the secretion of gastric juice, but if given soon after feeding they neutralize the acid of this secretion, and retard digestion. In cases of excessive acidity, with acid eructations, the administration of an alkali, such as the bicarbonate of soda, proves beneficial, but its action must be regarded as only palliative. Alkalies exert a sedative effect on the stomach, and relieve gastric pain ; they also neutra- lize the toxic effects of acids. On the Blood. — Alkalies, by reason of their diffusion- power, readily pass into the blood, so that only a small portion of them reach far into the small intestine. On entering the blood they undergo various changes, de- pending on their composition, the majority being pro- bably converted ultimately into carbonates. They are quickly eliminated by the kidneys, so that it is probable they do not increase the alkalinity of the blood to any Digitized by Microsoft® POTASSIUM AND ITS MEDICINAL SALTS 215 great extent ; in fact, after their conversion into car- bonates, but little is known of their precise action on the vital fluid. Acting as diuretics, they are excreted chiefly by the kidneys. 1. POTASSIUM AND ITS MEDICINAL SALTS. Sources. — From woodashes, from cream of tartar, and from the native nitrate. GENEEAL ACTIONS OF POTASSIUM SALTS. The actions of the different salts of potassium vary according to their nature, some, as the hydrate, being irritant and caustic ; others, as the nitrate and acetate, being diuretic ; while others, as the iodide and bromide, exhibit the action of their acid or salt radical. (1) IMMEDIATE LOCAL ACTION. In the mouth potassium temporarily checks the secre- tion of saliva. In the stomach, if given before feeding, it acts as a dilute alkali, stimulates the gastric follicles, increases the flow of gastric juice, and also acts as a sedative to the gastric nerves. If given after feeding it neutralizes the acidity of the contents of the stomach. (2) ACTION ON THE BLOOD. Potassium quickly enters the blood in the form of salts ; it increases the natural alkalinity of the plasma, in a transient manner, however, and also increases the number and quahty of the red corpuscles. (3) SPECIFIC ACTION. In larger doses potassium salts depress the muscular, nervous, and cardiac tissues. In the dog large doses are expelled by the act of vomition. Digitized by Microsoft® 216 VETERINARY THERAPEUTICS (4) EBMOTB LOCAL ACTION. Potassium salts are very rapidly excreted from the system, chiefly by the kidneys, to a less extent by the skin, respiratory passages and bowels, increasing the amount and the alkalinity of the excretions, their diuretic effect being generally due to their influence on the renal epithelium. The Medicinal Uses will be described under the heading of each salt. Potassii Carbonas — Cabbonate op Potassium. Potassii Bicarbonas— BicAEBONATB of Potassium. Preparation. — The Carbonate is obtained from pearl- ash, the product of lixiviation of woodashes by solution and crystallization. The Bicarbonate is prepared by saturating a strong aqueous solution of the carbonate with carbonic acid gas, and recrystallizing. Doses of the Bicarbonate. — Horses, gss. to §i. ; cattle, §1. to §i.ss. ; sheep and pigs, 3ss. to 3i. ; dogs, grs. x. to grs. Xi. Twice daily, properly diluted. General Actions. — The carbonates differ only in the degree of their action. The carbonate in sufficient amount and concentrated form acts as an irritant corrosive poison. The bicar- bonate does not possess this action, being less of an alkali and more of a saline, and is the salt preferred for internal use. It is antacid, also stomachic, soothing the gastric nerves. It increases the alkalinity of the blood and urine, and acts as a mild diuretic and diaphoretic. Externally both salts, in dilute solution, act as antacids to the skin, besides stimulating and cleansing when used in the familiar form of soap. Medicinal Uses — Internally. — In cases of dyspepsia the Digitized by Microsoft® POTASSIUM AND ITS MEDICINAL SALTS 217 bicarbonate is prescribed shortly before feeding to in- crease the flow of gastric juice when this is deficient ; at the same time it acts as a sedative to the gastric nerves. The bicarbonate of soda is, however, more commonly employed for this purpose. In rheumatism, acute and chronic, the bicarbonate is employed to neutralize the excess of acid in the blood, to increase the flow of urine, which it renders alkaline. In uric acid deposits occurring occasionally in dogs, the administration of bicarbonate tends to cause their removal. In calculi and deposits, occurring in the bladder and urethra of highly-fed rams, and chiefly consisting of the ammonio-magnesian phosphate, the administration of the bicarbonate freely diluted and in repeated doses often acts beneficially. In cystitis and in irritable conditions of the bladder, the bicarbonate is prescribed in combination with bella- donna or hyoscyamus. Externally. — In the early stages of eczema in dogs, characterized by weeping and great irritation, dilute solutions of the carbonates in combination with glycerine often act in a beneficial manner. In chronic skin affections in the dog, the carbonate of potash, in combination with sulphur, in the form of oint- ment such as the unguentum sulpho-alhalinum, as recom- mended by Professor Williams, is a very useful and efiScient application. In parasitic skin affections of all animals, the addition of carbonate of potash to the active ingredients applied is of great value in softening the cuticle, and enabling the remedy to penetrate to a greater depth, also neutraliz- ing the acid excretion. An emulsion of carbonate of potash, olive-oil and water forms an excellent applica- Digitized by Microsoft® 218 VETERINARY THERAPEUTICS tion for use after blisters, when the part becomes hard and scaly, possessing the advantages of allaying undue irritability, and not causing excessive softening of the parts, such as is apt to ensue after the use of oleaginous substances. Liquor Potassae— Solution of Potash. Potassa Caustica — Caustic Potash. Preparation. — The Liq. Potasses is prepared by boiling slaked lime in a solution of the carbonate and decanting. Caustic Potash is prepared from the liquor potassse by boiling it down quickly in a silver vessel and pouring into moulds. Caustic potash is a penetrating caustic seldom em- ployed in practice. Liquor potassee possesses similar actions to the carbonate, but the latter, being milder, is prescribed instead. Potassii lodidum — Iodide of Potassium (see lodum, p. 293). Potassii Bromidum — Beomide of Potassium (see Bromuni, p. 299). Potassii Nitras — Niteate op Potassium, Nitee, Salt- PETEB. Prepared from the native salt by crystallization from solution in water. Doses. — Horses, 7,ii. to |ss. ; cattle, gi. to gi.ss. ; sheep and pigs, 5ss. to 3i. ; dogs, grs. x. to grs. xx. Twice daily. Specific Actions. — Externally it is stimulant and re- frigerant, and when concentrated is an irritant to mucous surfaces. Internally. — In excessive doses it is a gastro-intestinal irritant, besides paralyzing the heart and nervous centres. Digitized by Microsoft® POTASSIUM AND ITS MEDICINAL SALTS 219 In medicinal doses it is very soluble and diffusible, and quickly enters the blood. Its precise action in the blood is not clearly understood, but when added in large amount to blood drawn from the body it retards coagu- lation. It is excreted by the kidneys chiefly, also from the bronchial glands and the skin, increasing the func- tions of these organs. It is a powerful diuretic, producing this effect by acting as a local vascular stimulant to the kidneys, thus differing from other potassium salts in this respect. Medicinal Uses. — As an alterative and febrifuge, nitrate of potassium is prescribed in febrile conditions and catarrhal affections, to promote the bronchial, cutaneous and urinary secretions, and to assist in the elimination of effete products. It is given either alone or with sulphate of magnesia, and is readily taken dissolved in the patient's drinking- water. As a diuretic it is employed in febrile affections, and for hastening the removal of effusions from serous cavities. In cases of renal disease its use requires care because of its action on the renal bloodvessels, other salts, such as the acetate and acid tartrate, being preferred when it is desired to increase the secretion of water and urea, by stimulating the renal epithelium, without dis- turbing the renal vessels. It is also useful in oedematous conditions of the limbs, lymphangitis, etc., in horses, and in such cases is often combined with other diuretics. In acute rheumatism, in combination with other remedies, it produces beneficial effects ; but these cannot be ascribed to any special action on the blood. Externally, in combination with sal ammoniac, it forms a refrigerating lotion, which is useful in reducing local inflammatory action. Digitized by Microsoft® 220 VETERINARY THERAPEUTICS Potassii Chloras — Chloeate op Potassium. Prepared by passing chlorine gas into a mixture of carbonate or chloride of potassium and slaked lime, boiling, evaporating, and separating the chlorate of potassium by recrystallization. Doses. — Horses, 3ii. to ^ss. ; cattle, §ss. to gi. ; sheep and pigs, grs. xx. to grs. xl. ; dogs, grs. v. to grs. xv. These doses must be modified according to circumstances, and may be administered in the food or drinking-water. Specific Actions. — In the mouth it increases the salivary flow ; also acts as a stimulant to the different portions of the respiratory mucous membrane, thus being a saline expectorajit. If administered in excessive doses, it acts as an irritant to the stomach and intestines. Its action on the blood is not clearly understood. If it be added to blood drawn from the body, it increases the power of coagulation, and causes firmness of the coagulum. It does not, as was once believed, yield up its oxygen to the blood, as it is eliminated chiefly by the kidneys in an unchanged condition, and its soluble power is slight. In toxic doses it disintegrates the red corpuscles, and causes the colouring matter and albumin, with a few corpuscles, to appear in the urine. Medicinal Uses. — As an internal antiseptic, the chlorate of potash is a very valuable agent ; although we are not able to explain the manner in which it produces its beneficial effects in cases of septicaemia, still, experience has proved its utility. In cases of purpura hemorrhagica it produces most beneficial results, either alone or in combination with preparations of iron ; it is advisable to prescribe at first a large dose, and to follow this with smaller amounts. It is evident that this drug possesses some special action on the blood, judging from the results obtained. Digitized by Microsoft® POTASSIUM AND ITS MEDICINAL SALTS 221 In hcRmo-alhuminuria, or ' red water,' in cattle, after attending to the bowels, the chlorate of potash in combination with albuminous substances gives excellent results, probably by improving the quality of the blood. As a sialagogue and saline expectorant chlorate of potash is useful in cases of laryngitis, pharyngitis, bronchitis, etc. Where there is difficulty in swallow- ing, it may be used in the form of gargle, or as an electuary in combination with extract of belladonna. For wounds or injuries of the mouth, tongue, and in aphthous eruptions and ulcerations, it is useful in the form of a mouth-wash or coUutorium. Potassii Acetas — Acetate of Potassium. Prepared by saturating acetic acid with carbonate of potassium, evaporating, and solidifying. Doses. — The same as those of the nitrate. Actions and Uses. — -These are similar to those of the nitrate, but the diuretic action is brought about in a different manner, as already stated. It enters the blood as a carbonate, and is chiefly excreted by the kidneys, causing profuse diuresis. It is prescribed in cases of dropsy depending on renal disease, where the use of the nitrate would be contra-indicated. Potassii Tartras Acida — Acid Taetbatb of Potassium, Ceeam op Taetak is a mild laxative and diuretic occasionally prescribed in veterinary practice. Potassii Permanganas — Permanganate of Potassium. Prepared by evaporating a mixture of black oxide of manganese, chlorate of potassium, and solution of caustic potash. Digitized by Microsoft® 222 VETERINARY THERAPEUTICS The most important use of this salt is as a disinfectant and deodorant. It is employed in solution, and readily evolves oxygen, but is superseded to a great extent by more efficient disinfectants. It is still employed by some practitioners as an injection for the uterus in cases of metritis, etc. The popular disinfectant known as Condy's Bed Fluid is a solution of permanganate of potassium and sodium. 2. SODIUM AND ITS MEDICINAL SALTS. Sources, — The chloride, the native nitrate, and native borax. GBNBEAL ACTIONS OF SODIUM SALTS. The salts of sodium resemble in their actions the salts of potassium ; but there are important differences to be noticed : (1) They have not the depressing effect on muscles and nerves, consequently they are far less poisonous when administered in full doses. (2) The salts of sodium are much less diffusible than those of potassium ; thus, they are more slowly absorbed and excreted, and in some instances act as saline purga- tives by passing into the small intestines. (3) The salts of sodium, compared with those of potassium, are less useful for the purpose of increasing the alkalinity of the blood in diseases such as rheumatism, as they are slowly absorbed, and when administered in full doses tend to pass off by the bowels. Sodii Bicarbonas — Bicaebonate of Soda. Prepared by saturating the carbonate of potassium with carbonic acid gas, or by the reaction of chloride of sodium and bicarbonate of ammonium. Doses. — Horses, 3ii. to gss. ; cattle, §ss. to §i. ; sheep and pigs, grs. xx. to grs. xxx. ; dogs, grs. x. to grs. xx. Digitized by Microsoft® SODIUM AND ITS MEDICINAL SALTS 223 The carbonate only differs in its degree of action from the bicarbonate, and the latter is the salt generally employed. General Actions. — Bicarbonate of sodium possesses the actions of sodium in general on all parts of the body. Administered before feeding, it increases the secretion of the gastric juice ; given after or with the food, it pre- vents excessive acidity, and undue fermentation of food. It also acts as a diuretic, increasing the water and solid constituents of the urine, and neutralizing the acidity of the same ; but these actions are less powerful than the corresponding salts of potash. Medicinal Uses. — The bicarbonate of soda, being less irritant than the corresponding salt of potassium, is pre- ferred in cases of indigestion, for which purpose it is generally combined with vegetable bitters, tonics, and aromatics. A combination with nux vomica and gentian is very useful in cases of indigestion depending on a want of tone in the stomach with a tendency to fermentation of the contents and flatulence ; this may be administered along with the food or after feeding. As a stomachic this salt is very useful in stimulating the flow of gastric juice. When this secretion is deficient, a portion of the salt at the same time is converted into the chloride, which assists the digestion of albumin. It also tends to liquefy mucus of a tenacious nature, which is found to exist in the gastric mucosa in cases of dyspepsia, and thus enables the gastric juice to reach the food without difficulty. Sodii Sulphas — Sulphate of Sodium, Glaubee's Salts. Prepared by adding carbonate of sodium to the residue left after the manufacture of hydrochloric acid. Doses. — As a purgative for cattle, lb. i. to lb. i. ss. ; Digitized by Microsoft® 224 VETERINARY THERAPEUTICS sheep, gii. to §iv. ; as a cholagogue and alterative for horses, §ii. to §iii., dissolved in the drinking-water. General Actions. — Sulphate of sodium is a saline purga- tive, resembling in its actions other purgatives of this nature, such as sulphate of magnesium. It possesses an immediate local action on the intestines, also stimulates the intestinal glands, and is constantly being absorbed and excreted by the intestinal vessels in its course along the intestine, causing purgation in the manner described at p. 85. It is also a direct cholagogue or true hepatic stimulant, acting directly on the hepatic cells, and increasing the secretion of bile, besides removing bile which is lodged in the duodenum. Given in small doses freely diluted, it is excreted almost unchanged by the kidneys. The phosphate of sodium has similar actions. Medicinal Uses. — It is prescribed for both horses and cattle in eases where we wish both to stimulate the liver and to act on the bowels. Unless in large doses, it has no purgative effect on the horse, and even then is un- certain in its action. Nevertheless, in moderate doses it has a laxative effect, and is useful in cases of congestion of the liver. In cattle, compared with sulphate of mag- nesia, it is slower in its action as a purgative, and both drugs are occasionally combined. As a cholagogue in the dog, it is seldom suitable, because of the great irritability of the stomach which is generally present in hepatic dis- orders of this animal. Sodii Hyposulphis — Hyposulphite op Soda. Prepared by passing sulphurous acid gas into a solution of carbonate of soda with sulphur. Doses. — Horses and cattle, 3ii. to §ss. ; dogs, grs. v. to grs. X. , repeated twice or three times daily. Digitized by Microsoft® SODIUM AND ITS MEDICINAL COMPOUNDS 225 General Actions. — Hyposulphite of soda is absorbed as the sulphate, and is not decomposed into the sulphite or free sulphur in the system, such as was once supposed. As an internal antiseptic it has not acted up to the expectations of those who suggested it for this purpose, and other drugs are far more satisfactory and reliable. Clinical experience, however, proves its value in cases of distemper in dogs, given in doses of from two to six grains, according to the size of the dog, and combined with quinine it modifies very considerably the virulence of the affection. Sodii Chloridum — Chloeidb of Sodium, Common Salt. Source. — Native. General Actions. — This agent is necessary in the system of all animals for the maintenance of health. It pro- motes digestion and assimilation, and natural instincts compel animals to seek for it when there is a deficiency of it in foods or pastures. Internally, in moderate doses, the chloride of sodium is stomachic. In toxic doses it acts as an irritant, while in full doses is cathartic, and acts as an emetic in those animals capable of the power of vomition. Cases are recorded of the toxic effects of salt in pigs, causing gastro-enteritis and lesions of the nervous system. Medicinal Uses. — As conducive to health, it is always well to allow a piece of rock-salt in the manger of the horse, and convenient to cattle and sheep. Salt increases the secretion of saliva and of gastric juice, thus acting as a stomachic, being as necessary for animals as for human beings. As a cathartic it is more soluble and more rapidly absorbed than sulphate of magnesia, hence it is some- times combined with the latter, half a pound of each 15 Digitized by Microsoft® 226 VETERINARY THERAPEUTICS being given as a dose dissolved in a proper proportion of . water. It is also prescribed in various parasitic affections of the alimentary canal of young animals in combination vyith tonic agents, and is popularly employed as an emetic for the dog. Externally it is sometimes used in the form of a re- frigerating lotion in combination with nitrate of potassium and chloride of ammonium, in the proportions of one of each to thirty of water, which produces a lotion of very' low temperature. Sodii Biborate — Boeax (see Acid. Boricuni, p. 319). Sodii Bromidum (see Bromum, p. 299). Sodii lodidum (see lodum, p. 293). Sodii Salicylas. Sodii Hypophosphis. 3. AMMONIUM AND ITS MEDICINAL COMPOUNDS. Sources. — All the medicinal preparations and com- pounds of ammonium are derived directly or indirectly from the chloride, which is obtained from ammoniacal gas-liquor. GENEEAL ACTIONS OF AMMONIUM SALTS. These resemble to a certain extent those of potassium and sodium, but are much more volatile, quicker in their action, and more powerful. (1) IMMEDIATE LOCAL ACTION. Externally ammonia acts as a stimulant to the cutaneous nerves and structures, causing a sensation of pain, and dilating the vessels. If the application be pro- longed and the vapour confined, vesication may result, otherwise it acts as a rubefacient. Digitized by Microsoft® AMMONIUM AND ITS MEDICINAL COMPOUNDS 227 Internally, when inhaled by the nostrils, ammonia acts as a powerful general stimulant, producing in a reflex manner excitation of the vaso-motor centre, and raising blood-pressure. In the stomach a large dose, such as of the carbonate of ammonia, well diluted, acts in the dog as an emetic. Medicinal doses act as carminatives and reflex general stimulants, besides possessing an antacid effect if given after feeding. If given before feeding it stimulates the secretion of gastric juice, being generally employed in the form of an alkaline stomachic mixture. On the intestines, in medicinal doses, ammonia does not appear to have any appreciable immediate local action. (2) ACTION ON THE BLOOD. Ammonia is rapidly absorbed into the blood ; it diminishes the tendency to coagulation, and increases the alkalinity of the plasma. (3) SPECIFIC ACTION. It is a general stimulant, acting on the central nervous system, the spinal cord, the respiratory centre, the heart, and general blood-pressure. It increases the production of urea, in part by its own decomposition with carbonic acid in the liver. In toxic doses the effects vary with the preparation em- ployed ; but all after primary stimulation cause paralysis of the spinal cord, motor centres, and cerebrum. (4) EBMOTE LOCAL ACTION. Ammonia is excreted by the kidneys, also by the mucous membranes, especially by the respiratory mucous mejnhrane. It is changed to the form of nitric acid, and probably also as urea, and thus increases the amount of Digitized by Microsoft® 21% VETERINARY THERAPEUTICS urea in the urine, while it tends to render the excretion acid as well as increasing its volume, the chloride of ammonium possessing these actions more fully. It in- creases the bronchial secretion, thus acting as an expec- torant. On the shin it has a diaphoretic effect, most marked in the acetate of ammonium. On the Intestines. — Ammonia remotely increases the secretions of the intestinal glands, and, if given in large doses, will cause purgation. The medicinal uses will be described under the heading of each preparation of ammonium. Liquor Ammoniae Fortior — Steong Solution of Ammonia, Spirits op Haetshoen. Water containing 32-5 per cent, of gaseous ammonia. Liquor Ammonise — Solution of Ammonia. Water containing 10 per cent, of gaseous ammonia. General Actions. — These possess the chief actions of ammonia. The hq. ammoniae fort, is a topical irritant, and unless largely diluted it causes violent irritation of the mouth, throat, and mucous membrane of the stomach. Mistakes have occasionally arisen in administering this prepara- tion instead of the milder forms of ammonia. Professor F. Smith, in experimenting with this drug, injected into the jugular vein of a mule half an ounce of the strong solution, followed shortly after by another half-ounce, with no apparent effect. Another half-ounce was injected, and in forty minutes from the first injec- tion there were symptoms of colic manifested, the animal looking towards the sides, rolling, and pawing frequently. There was quivering of the muscles of the sides and Digitized by Microsoft® AMMONIUM AND ITS MEDICINAL COMPOUNDS 229 flanks, and the animal made constant attempts, as if wishing to urinate. The symptoms became modified, and had disappeared next morning. It was destroyed, and there was found extensive phlebitis from the seat of injection to the chest, with discoloration of the muscles around the injection. In cases where the strong solution of ammonia has been administered by mistake, the most effectual anti- dotes are dilute acids, such as vinegar, and a free allow- ance of demulcents and diluents. Medicinal Uses. — The strong solution of ammonia is not used internally. The liquor ammonise is employed as a powerful stimulant in cases of narcotic poisoning in doses of from §ss. to |i. for horses and cattle, and from T\\ XX. to 3ss. for dogs. It is necessary here to state that all preparations of ammonia should be properly diluted with water before administration, or, better still, mixed with cold gruel or mucilaginous substances, so as to avoid the danger of irritating the mucous membrane of the mouth and throat. The liq. ammoniae fort, gives off strong fumes, which are occasionally used as an inhalation to overcome shock, or to act as a general stimulant in cases of narcotic poison- ing in dogs. The liquor ammonias is prescribed in cases of tympanitis in horses and cattle, neutrahzing the gas present, acting as an antacid, and stimulating the stomach and intes- tines to healthy action. Externally the strong solution of ammonia is largely employed in the form of liniments as a stimulant and mild counter-irritant in cases of rheumatic affections of muscles and joints, in laryngitis and pharyngitis ; and to prevent fomented surfaces, such as the chest walls, Digitized by Microsoft® 230 VETERINARY THERAPEUTICS becoming chilled; also as an application for the irrita- tion caused by the stings of insects. Ammonia should not be used strong enough to act as a vesicant, as its action is likely to leave a blemish on the skin if prolonged. The following form convenient liniments for the pur- poses of mild counter-irritation : R Liq. ammon. fort., gi. 01. terebinthee, ^i. 01. olivsB, gvi. M. Ft. lin. For dogs the following is a useful liniment in cases of strains, bruises, etc., also for muscular strains in horses after hot fomentations have been applied : R Tr. arnicee, §iv. Tr. camphorge, §iv. Liq. ammon. fort., §ss. Sapo mollis, §ii. Aqua ad Oi. M. Ft. lin. Spiritus Ammoniae Arotnaticus — Aeomatic Spieit op Ammonia, Sal Volatile. Prepared by dissolving the strong solution of ammonia and the carbonate of ammonia in water and rectified spirit, in the proportion of four ounces of the carbonate and eight ounces of the liq. ammoniae fort., to six pints of spirit and three pints of water, and flavouring with oil of nutmeg and oil of lemon. Doses. — Horses and cattle, §ii. to giv. ; dogs, 3ss. to 3i.) repeated at intervals as required. Medicinal Uses. — The aromatic spirit is a convenient preparation of ammonia. Digitized by Miuroaufi® AMMONIUM AND ITS MEDICINAL COMPOUNDS 231 As a carminative and reflex general stimulant we em- ploy it in cases of dyspepsia, both in horses and dogs. It is also useful, in combination with other agents, such as the oil of turpentine, in cases of tympanitis, in both horses and cattle, administered in raw linseed-oil. As an antacid it is prescribed in combination with other agents possessing this property, in the form of alkaline stomachic mixtures, administered after feed- ing. As a general stimulant it is useful in cases of milk- fever in cows, where stimulant effects are indicated in the secondary stages. The effects being transient, it is essential that the doses be repeated at intervals, and alcohol is often pre- scribed in addition, with advantage. Similar remarks refer to the irritating effect of this preparation of ammonia on the mucous membrane of the mouth as of the liq. ammonise, it being necessary to have it properly diluted before administration. Ammonii Carbonas — Oaebonatb of Ammonia, Sbsqui- CAEBONATB OF AmMONIA. Prepared by subliming a mixture of chloride of ammonium and carbonate of calcium. Doses. — Horses, 5ii. to gss. ; cattle, §ss. to gi. ; dogs, grs. iii. to. grs. viii., either given in the form of bolus or dissolved in gruel, and repeated at intervals as re- quired. Medicinal Uses. — The carbonate being more permanent in its effects than the other preparations of ammonia, is preferred as a stimulant in certain respiratory and cardiac affections. As an antacid and diffusible stimulant it is prescribed in cases of atonic dyspepsia, such as we meet with in Digitized by Microsoft® 232 VETERINARY THERAPEUTICS cattle, manifested by recurring attacks of tympanitis. For this purpose it is combined with a vegetable tonic, such as gentian, and a carminative, such as ginger, and administered twice daily in vrarm ale. As a stimulant expectorant it is indicated in cases of bronchitis, as it promotes bronchial secretion and ex- pectoration, being especially useful when the secretion is thick and scanty in the secondary stages, and the heart's action weak, with general debility of the system. In addition it stimulates the heart and respiratory centre. For such purposes it is combined with camphor and chlorate of potash, and a bitter tonic such as gentian, and administered in the form of bolus twice daily. As a stimulating emetic it is sometimes prescribed in canine practice, combined with ipecacuanha in cases of bronchitis. Ammonii Chloridum — Chloride of Ammonium, Sal Ammoniac. Prepared by neutralizing ammoniacal gas liquor with hydrochloric acid. Doses. — Same as the carbonate. Medicinal Uses. — Internally. — As an expectorant the chloride of ammonium is sometimes prescribed in the second stages of bronchitis, also iu cases of chronic bronchitis. As a cholagogue it acts directly on the liver, and is occasionally prescribed in cases of chronic torpidity of this organ, and also in chronic hepatitis. Externally it is prescribed as a refrigerating lotion in combination with nitrate of potassium and chloride of sodium, dissolved in a proper proportion of water. Digitized by Microsoft® A MMONimi A ND ITS MEDICINA L COMPO UNDS 233 Liquor Ammonii Acetatis Fortior— Steong Solution OF Acetate of Ammonium. Prepared by neutralizing carbonate of ammonium by acetic acid, and adding water. LicLUor Ammonii Acetatis — Mindererus' Spirit. Prepared by adding one part of the strong solution of acetate of ammonium to five parts of water. Doses of the Strong Solution. — Horses, _^ii. to _^iii. ; dogs, ni^xx. to 3i. Of the weaker solution twice or three times these doses are required. The strong solution is the best preparation for horses, taking up less bulk. Medicinal Uses. — The acetate of ammonium acts as a feeble stimulant compared with other preparations of ammonia. It is prescribed as a diaphoretic, febrifuge, and a mild diuretic and expectorant in febrile affections and acute respiratory disorders, and is generally combined with the spts. seth. nit. , and a saline such as the nitrate of potash, and repeated at intervals of two or three hours. Its diaphoretic effect in the horse is aided by the use of warm clothing and a proper temperature of the surround- ings, with frequent administration of the drug. In the dog the acetate of ammonium acts as a diuretic instead of a diaphoretic, and is a useful agent in dis- temper and in catarrhal affections, being combined with other medicinal preparations as the circumstances of the case may indicate. A useful febrifuge mixture for the dog is prepared with the acetate of ammonium, and the spts. seth. nit., while if there be irritation of the larynx or bronchii present, the tincture of camphor and chlorate of potash may be added with advantage. The effects of these diffusible Digitized by Microsoft® 234 VETERINARY THERAPEUTICS stimulants being transient, it is necessary to prescribe them so as to have the doses repeated at stated in- tervals. Ammonii Bromidum (see Bromuni, p. 299). 4. CALCIUM AND ITS MEDICINAL SALTS. Sources. — The chief sources are carbonate of lime, the native sulphate and bone-ash. Calcii Hydras — Slaked Limb. Prepared by slaking lime with vvater. Preparations. LicLUor Calcis — Lime-water. Prepared by shaking up slaked lime with distilled water and decanting. Each fluid ounce contains half a grain of lime. LINIMENTUM CALCIS. Prepared by mixing equal parts of lime-water and olive-oiL Also termed carron oil. Actions and Uses. — Externally lime in the form of the hydrate is caustic, but is seldom used for this purpose ; it attracts the water of the part, and combines with the albumen. In the form of the linimentum calcis it is a valuable application to scalds and burns, and is often useful in cases of extensive eczema in dogs, with profuse weeping discharges, acting as an astringent and desiccajit. Internally the immediate local action is antacid and astringent, it being administered in the form of the liquor calcis. In the stomach and intestines it combines with the free acids of the contents, and prevents the formation of Digitized by Microsoft® CALCIUM AND ITS MEDICINAL SALTS 235 coagulated masses of casein occurring in young animals, especially those artificially fed on milk, about one-fourth lime-water being added to the milk. It also acts as a general gastric sedative, depressing the glands of the stomach, and is hence prescribed in cases of vomiting in dogs depending on a condition of acid dyspepsia, in the form of the saccharated solution of lime, which is prepared by digesting slaked lime and sugar in water, and decanting, in the proportion of an ounce of the former with two ounces of the latter to a pint of water, and administered in doses of from twenty to sixty minims mixed with milk. On the intestines the astringent action is due partly to the antacid property, and partly to a sedative effect on the intestinal glands, and for this purpose the liquor calcis is administered in eases of diarrhoea in calves and lambs in doses of two ounces for the former, and half an ounce to one ounce for the latter, combined with tincture of gentian and ginger. Lime-water may be employed as an antidote for poisoning by the mineral acids and oxalic acid. Creta Preparata — Peepaeed Chalk. Prepared from the native carbonate of calcium by elutriation and drying. Incompatibles . — All acids and sulphates. Doses. — Horses, ji. to §ii. ; cattle, gii. to §iv. ; sheep and pigs, 3ii. to 3iv. ; dogs, grs. x. to ^i. Actions and Uses. — Prepared chalk possesses all the actions of the liquor calcis just described, but it is less soluble, and retains its antacid properties for a longer period in the alimentary canal, thus being more effi- cacious as an antacid and astringent throughout the in- testines. Digitized by Microsoft® 236 VETERINARY THERAPEUTICS It is prescribed in cases of diarrhcea, combined with other astringents, and is believed to soothe the irritable mucous membrane, and to leave a protecting film of the carbonate thereon. In severe cases of diarrhoea in all patients it is com- bined with antispasmodics, such as opium or chlorodyne, with very beneficial effects. Attention, however, must be directed in such cases to ascertain, if possible, the cause, which, if depending on the presence of an irritant, will require appropriate treatment, as previously referred to. Calx Chlorinata — Chloeinated Limb. A compound directly of lime and chlorine. Actions and Uses. — This compound is not used inter- nally. Its chief use is as a disinfectant and deodorizer, producing its effects by decomposing substances such as ammonia, sulphuretted hydrogen, etc., being ultimately converted into the chloride of calcium. It also pre- vents the development of germs, and is employed for the purposes of disinfecting stables and cowsheds, shaken about as a dry powder ; but other agents are more reliable, and not possessed of its disagreeable properties. Calcii Phosphas — Phosphate op Calcium. Prepared by dissolving bone-ash in hydrochloric acid, and adding water and solution of ammonia, is sometimes prescribed in cases of malnutrition and anaemia in young animals, also in cases of rickets, and other bone affec- tions. Calcii Hjrpophosphis (see Phosphorus, p. 276). Calx Sulphurata (see Sulphur, p. 302). Digitized by Microsoft® MAGNESIUM AND ITS MEDICINAL SALTS 237 5. MAGNESIUM AND ITS MEDICINAL SALTS. Source. — All the medicinal preparations are derived directly or indirectly from the sulphate of magnesia, which itself is prepared from magnesian limestone or dolomite, by solution in sulphuric acid and purification. Magnesii Sulphas — Sulphate op Magnesia, Epsom Salt. Incompatibles. — Alkaline carbonates, lime-water. Doses. — As a purgative for cattle: Adults, lb. i. ; calves, two or three months old, 5iii. to giv. ; sheep and pigs, giv. It is given dissolved in ten to fifteen parts of warm water, with a carminative such as an ounce or two of powdered ginger, and a pound of treacle, which both assists the purgative action and also conceals the nauseous taste. The chloride of sodium is combined with the sulphate of magnesia by some practitioners in half doses of each. As a febrifuge and alterative %\. to §11. is prescribed for horses, generally combined with the nitrate of potash ; for cattle, Jii. to ^iv. General Actions. — Given in sufficient amount the sulphate of magnesia acts as a saline hydragogue cathartic, causing little stimulation of the muscular coat of the intestines. In the stomach it is slowly absorbed, the chief action being in the intestines. In the intestines it has a low diffusing power, is slowly absorbed, and produces its characteristic hydragogue action in three ways : (1) It causes an increased flow of fluid from the blood into the intestinal canal. (2) It retards the absorption of the fluid present in the canal. Digitized by Microsoft® 238 VETERINARY THERAPEUTICS (3) It stimulates the intestinal glands, and causes great increase of the intestinal secretions. The total result is the free evacuation of a large quantity of fluid by the intestines ; there being also a slight amount of increased peristalsis, the major por- tion of the drug is removed by the intestine, and thus excreted, a certain amount being carried off by the kidneys. As a purgative, it is more rapid in its action in cattle than sulphate of soda. In small doses sulphate of magnesia is likely to be retained longer in the intes- tines, being then absorbed into the blood, and excreted chiefly by the kidneys, causing more or less diuresis, rendering the urine more alkaline, and dissolving uric acid. On the Liver. — According to the results of experiments, the sulphate of magnesia does not directly increase the flow of bile, thus differing from the sulphate of soda, which is a direct cholagogue. It has, however, a bene- ficial action in clearing away unabsorbed bile in the duodenum, and thus preventing its reabsorption. Medicinal Uses. — As a purgative the sulphate of mag- nesia is not used in the horse, as its action in this animal is uncertain, sometimes causing violent purgation, and at other times causing considerable diuresis. In the dog, the purgative effect is irregular, and its nauseous bitter taste is apt to induce vomition in this animal. For ruminants, however, experience proves that it is a very valuable purgative, generally acting in from twelve to fifteen hours, and is prescribed in the manner already mentioned. It is necessary to remark, however, that the practice of administering large and repeated doses of this drug to cattle is irrational, and productive of injurious results Digitized by Microsoft® MAGNESIUM AND ITS MEDICINAL SALTS 239 when the cause of the loss of intestinal action is due to a paralyzed condition of the intestinal walls, or to gastric inflammation. In such instances we find the result to be a tympanitic state of the alimentary canal, with great depression of the system, effects which tend to aggravate the already existing condition. If a dose of proper strength does not succeed after a reason- able time, then we should prescribe oleaginous aperients, and adopt a line of treatment best calculated to over- come the cause of the arrested action of the intes- tines. As a fehrifiige and alterative the sulphate of mag- nesia is a very useful therapeutic agent in all patients. It improves the appetite, maintains a healthy action of the bowels, removes excrementitious matters from the blood, lessens abnormal temperature, and is prescribed in febrile affections, combined with other salines, such as the nitrate of potash, given dissolved in the drinking- water, and left in the stall convenient to the patient, so that he can drink at pleasure. Two ounces of sulphate of magnesia and half an ounce of nitrate of potash, given twice daily in this manner, prove very useful in cases of influenza and acute respiratory affections. I7i atonic torpidity of the bmoels in cattle, two or three ounces of sulphate of magnesia, with one drachm of powdered nux vomica and one ounce of powdered gentian, administered twice daily, forms a very useful prescription. As a diuretic it is prescribed in small doses in chronic affections of the kidneys, and in cases of dropsical effusions. As an antidote to poisoning by salts of lead, the sulphate of magnesia is very effectual, converting them Digitized by Microsoft® 240 VETERtNA RY THERAPEUTICS into insoluble sulphates, and also promoting the action of the bowels, which are apt to lose their tone as a result of the toxic agent. Magnesii Carbonas Ponderosa— Heavy Caebonate OP Magnesia. Magnesii Carbonas Levis — Light Caebonate of Magnesia. Preparation. — These two salts only differ as regards their physical properties. Both are prepared by mixing solutions of sulphate of magnesia and carbonate of sodium. In the case of the former salt the solutions are mixed when boiling, in the latter cold dihUe solutions of both are employed. Actions and Uses. — The carbonates of magnesia neu- tralize excessive acidity of the stomach and intestines, forming salts which have a laxative action, and yielding carbonic acid. They increase the alkalinity of the blood, and are prescribed as laxative antacids in cases of acidity and flatulence in foals, calves, and dogs, given with the spts. ammon. aromat. between the hours of feeding, in doses of from 5ii. to gss. for foals apd calves, and grs. x. to 3ss. for dogs. As antidotes for the mineral acids, oxalic acid, mer- curial, arsenical and copper salts, they form comparatively insoluble or innocuous compounds, and in large quantities prevent the absorption of alkaloids by rendering the contents of the stomach alkaline. Digitized by Microsoft® LEAD AND ITS MEDICINAL SALTS 241 CHAPTBE III. INORGANIC MATERIA MEmOA—Co7iti7iued. GROUP II.— THE METALS. FoK convenience of description, according to their actions and uses, we may subdivide the metallic elements into sub-groups as follows : 1. Plumbum ; Argentum ; Zincum ; Cuprum ; Alu- minium. 2. Ferrum. 3. Hydrargyrum. ■ 4. Arsenium ; Antimonium ; Bismuthum ; Phosphorus. (Phosphorus is a non-metallic element, but is included under this heading because of a similarity in its actions to antimony and arsenic.) Sub-Geoup I. PLUMBUM— LEAD, AND ITS MEDICINAL SALTS. GENBEAL ACTIONS OF LEAD SALTS. (1) IMMEDIATE LOCAL ACTION. Externally the salts of lead possess certain definite actions of importance to the therapeutist. Applied to wounds or exposed mucous surfaces, the following phenomena occur : (a) They precipitate the albumen in the fluids found either covering the surface or flowing as a discharge. (b) They coagulate the protoplasm of the young cells of the superficial layers of the part. 16 Digitized by Microsoft® 242 VETERINARY THERAPEUTICS (c) They act on the local circulation of the part, causing active contraction of the small arteries and veins, diminishing the blood-flow, and preventing the escape of plasma and blood-cells through the walls of the vessels. {d) They depress the local nerve endings in the part. The total effects of these actions are, astringent, seda- tive, and desicca7it. Internally they act as astringents on the mucous mem- brane of the mouth and throat. In the stomach and intestines the secretions are diminished, the vessels contracted, and the peristaltic movements retarded, the salt being converted into an albuminate. (2) ACTION ON THE BLOOD. Lead salts are absorbed as albuminates ; they pass rapidly through the blood, and if administered for some time are said to render the vital fluid more watery, and to diminish the number of red corpuscles. (3) SPECIFIC ACTION. Lead is taken up by the tissues freely from the blood, and retained firmly in the form of an albuminate, chiefly by the liver and kidneys, also by the central nervous system, and in the bones. Certain toxic eflfects are pro- duced as a result of the presence of lead in the tissues, the condition being termed plumbism. The chief symptoms of this condition are dyspepsia, constipation, colicky pains, cramps of the muscles, especi- ally the extensors, terminating in paralysis ; the pulse is full, tense and infrequent, the blood-pressure raised, the urinary excretion disturbed, the central nervous system is first irritated, evidenced by convulsions, and succeeded by paralysis The appearance of a blue line at the edges of the gums is often observed. Digitized by Microsoft® LEAD AND ITS MEDICINAL SALTS 243 Whether the effects produced are due to the irritant action of lead on the involuntary muscular tissue of the ahmentary canal and bloodvessels, or to its primary action on the central nervous system and nerves, and secondarily on the muscles, bloodvessels, etc., is a ques- tion on which authorities are not agreed. (4) remote" LOCAL ACTION. Lead is slowly excreted by the kidneys, liver, skin, and milk. In the intestine the portion which is excreted by the liver is reabsorbed, again excreted, and is finally removed from the body in the form of the black sulphide of lead. Antidotes to Lead Salts. — In cases of acute poisoning in dogs, emetics should be administered. In chronic poisoning, sulphate of magnesia or potassium iodide con- vert the lead in the system into insoluble salts, and should be prescribed daily at intervals, the use of occa- sional doses of linseed-oil hastening their removal from the system. Plutnbi Oxidum — Oxide op Lead, Lithaege. Prepared by roasting lead in a current of air. Medicinal Uses. — The oxide of lead is not prescribed internally. Externally it is used in the form of the oleate of lead, or lead plaster, prepared by combining it with olive-oil and water. This plaster is employed for the purpose of bringing the edges of small wounds together, or for giving support to sutures in the case of extensive wounds. The oxide of lead is sometimes used locally as a desiccant and astringent. Digitized by Microsoft® 24 1 VETERTNARY THERAPEUTICS Plumbi Acetas — Acetate op Lead, Sugak op Lead. Prepared by heating oxide of lead in acetic acid and water. Doses. — Horses and cattle, Jss. to Ji. ; dogs, gr. i. to grs. iv. Liquor Plumbi Subacetatis — Goulaed Bxteact. Prepared by boiling together acetate of lead 5 parts, oxide of lead 3J parts, and water 20 parts, filtering, and adding water. Incoinpatihles. — All vegetable astringents, preparations of opium, alkalies, lime-water, iodide of potassium. Medicinal Uses — hitemally the acetate of lead is pre- scribed as a powerful hcemostatic to check haemorrhage from the stomach and intestines, and also from the lungs. As mi astringent it is prescribed in cases of obstinate diarrhoea and dysentery, being usually combined with opium, its beneficial effects in this respect being referable to its local action on the alimentary canal. Externally the acetates of lead are extensively em- ployed as astringents and local sedatives. Goulard's extract is preferred for external application, being more soluble, and not crystallizing. In cases of eczema in dogs, with raw surface, copious weeping and intense irritation, the careful use of a lotion consisting of liq. plumbi diacetatis, §ii., glycerinum, §ii., aqua, §iv., is often productive of benefit; but it is necessary to be aware of the danger of the animal licking the parts. In cases of mud fever and grease in horses, a lini- ment consisting of the liquor plumbi subacetatis with Digitized by Microsoft® LEAD AND ITS MEDICINAL SALTS 245 glycerine and olive-oil, in the proportion of one to four parts, is a very useful application. In strains, superficial inflammations, etc., the acetate of lead mixed with spirits and water forms a refrigerating astringent lotion. It is sometimes prescribed as a lotion in catarrhal inflammations of the eye, but is contra-indicated when there is any abrasion of the cornea present, as tending to form an insoluble lead albuminate, causing an opacity difficult to eradicate. Solutions mixed with the tincture of opium, although chemically incompatible, form useful lotions in cases of bruises, contusions, etc. A weak lotion of the same is of benefit in the first stages of canker in the ears of dogs. Acetate of lead and sulphate of zinc, dissolved in water, in the proportion of 1 part of the former and I part of the latter to 30 of water, forms the time- honoured White Lotion, so extensively used in veterinary practice. This preparation is chemically incompatible, acetate of zinc being formed in solution, and sulphate of lead being thrown down as a precipitate ; but experience proves it to be a valuable astringent, cooling lotion in cases of collar and saddle-galls, irritated surfaces, unhealthy wounds, ulcers, etc. Plumbi Carbonas — Caebonate op Lead, White Lead. Prepared by exposing lead to the vapour of acetic acid, and simultaneously to air charged with carbonic acid. Medicinal Uses. — It is not used internally. Externally, it is occasionally employed as an astringent and desic- cant. Digitized by Microsoft® 246 VETERINARY TUERAPEUTICS Mixed with linseed-oil it makes a valuable application in cases of burns, and also in local blood-poisoning the result of septic matter entering a wound. Painted on, it forms a protective covering, and diminishes the extreme pain existing in the part, by depressing the nerve endings. Plumbi lodidum — Iodide op Lead. Prepared by mixing solutions of nitrate of lead and iodide of potassium, and drying the precipitate. Medicinal Uses. — In the form of an ointment (1 to 7) the iodide of lead is sometimes used as an absorbent application to enlarged joints, glandular swellings, etc., the effects being referable to the iodine, probably assisted by the lead. ARaENTUM— SILVER. The salt of silver used in veterinary practice is the nitrate. Argenti Nitras — Niteatb of Silvee, Ldnae Caustic. Prepared by dissolving silver in dilute nitric acid. General Actions. — Externally the nitrate of silver acts as a caustic when applied in the solid form or in strong solution. Solutions of a moderate strength, when applied to the broken skin or a mucous membrane, form an albuminate which coats the surface with a thin layer, also coagula- ting the protoplasm of the young cells. The arteries, veins and capillaries of the part are actively contracted, and in animals with skins of a light colour the superficial layers are stained black, being pre- viously of an opaque white at the point of application. Digitized by Microsoft® NITRATE OF SILVER 247 Internally the nitrate of silver combines with the albuminous fluids and chlorides in the mouth, and when properly diluted acts as an astringent. In the stomach, in medicinal doses, it is decomposed by the acid present. It enters the blood in the form of an albuminate, being slowly absorbed, and retained in the metallic form in all 'the connective tissues, staining exposed parts of a permanent blackish-brown colour. Toxic doses cause irritation of the stomach and intes- tines, with prostration, convulsions, and paralysis, these latter effects being probably central in origin. The best antidote is common salt, which forms the insoluble and inert chloride of silver. Medicinal Uses. — As a tonic and astringent it is some- times prescribed in canine practice, in chronic nervous diseases, or in chronic diarrhoea and dysentery, in doses of -g^ to J^ grain in pills. Externally it is the caustic most universally employed, as its effects are limited to the area of application, and it is less irritating than others. As a stimulant to indolent wounds and ulcers the nitrate of silver is very useful, promoting healthy growth, and suppressing excessive granulations, besides forming a protecting covering to the part. In conjunctivitis a solution of the nitrate of silver con- taining from half a grain to two grains to the ounce is very useful; a few drops inserted into the eye three times daily promotes a healthier action in the mem- brane, and relieves irritation. La opacity of the cornea a solution containing four to six grains to the ounce of distilled water, carefully applied daily with a camel's-hair brush, often succeeds in rendering the part clear. It is recommended in erysipelas, applied two or three Digitized by Microsoft® 248 VETERINARY THERAPEUTICS times to the inflamed surface, and extending a few inches beyond it, in the form of a strong solution containing 80 grains to i drachms of water. In cases of chronic inflammation of the larynx and pharynx, sometimes met with in dogs, a solution of the nitrate of silver applied to the part by means of a probang or brush produces beneficial results. The best solvent for the nitrate of silver is nitrous ether, as this dissolves the fatty matters of the skin, and enables the solution to produce a uniform action over the surface, instead of running into drops. This solution acts much more strongly than an aqueous one, and hence requires to be made of less strength. ZINCUM— ZINC, AND ITS MEDICINAL SALTS. General Incompatibles of Zinc Salts. — Alkalies and their carbonates, lime-water, acetate of lead, nitrate of silver, astringent vegetable preparations. GBNBEAL ACTIONS OF ZING SALTS. (1) IMMEDIATE LOCAL ACTION. The salts of zinc resemble those of lead, silver, and copper in their local actions ; they act as caustics in their stronger forms, and as astringents in their weaker forms. The difference in degree of the actions of zinc salts depends on their diffusion-power and affinity for water, and on their solubility. Thus, the chloride of zinc acts as a caustic, applied in sufficient strength locally, while the sulphate acts as an astringent and stimulant. Internally the effect of zinc on the stomach is that of a local irritant, acting as a direct emetic, in those animals capable of the act of vomition. In the intestines, in Digitized by Microsoft® ZINC AND ITS MEDICINAL SALTS 249 large doses, zinc acts as an irritant, but in medicinal doses it has an astringent effect. (2) ACTION ON THE BLOOD, AND SPECIFIC ACTION. Zinc is slowly absorbed, probably as an albuminate. We possess no knowledge concerning its action on the plasma or corpuscles which is of any therapeutical value. In the tissues of the body it does not become fixed, but acts as a direct depressant to the nerve-centres when administered in continued doses. (3) REMOTE LOCAL ACTION. Zinc is excreted by the kidneys in small quantities, also by the mucous surfaces and skin. It produces a remote astringent effect on those parts by which it leaves the system. Zinci Oxidum — Oxide of Zinc. Prepared by heating the carbonate. Medicinal Uses. — The oxide of zinc is astringent and desiccant, and is used in cases of eczema in which there is a raw indolent surface, either in the form of a dusting powder or as an ointment. It is also useful in mild cases of grease and cracked heels, in the form of unguentum zinci, prepared with the oxide of zinc 1 part, benzoated lard 5| parts. A similar ointment is also prescribed in cases of canker of the ear in dogs. Zinci Carbonas — Carbonate of Zinc, Calamine — is similar in its actions and uses to the oxide. Digitized by Microsoft® 250 VETERINARY THERAPEUTICS Zinci Sulphas — Sulphate op Zinc, White Vitbiol. Prepared by the action of dilute sulphuric acid on granulated zinc. Doses. — As an astrmgent and tonic : horses, 5ss. to ^i- ," dogs, gr. i. to grs. iii. As an emetic for dogs, grs. x. to grs. xxx. dissolved in two ounces of warm water. Medicinal Uses. — As an emetic the sulphate of zinc is safe, prompt, and effectual for the different purposes for which emetics are indicated. It acts with little prostration or nausea, producing its effect by its local irritant action on the stomach, thus being a direct emetic. It is sometimes prescribed as a tonic and astringent, but is inferior to other drugs in these respects. In nervous affections, such as chorea, epilepsy, etc., it is prescribed in canine practice, often with beneficial results, the doses being gradually increased. Externally the sulphate of zinc is very useful as a sti- mulant and astringent application in cases of ulcers, un- healthy wounds, etc., limiting the amount of discharge, checking excessive weak granulations, and promoting a tendency to reparative action. For these purposes it is dissolved in 30 to 60 parts of water. In inflamed conditions of the conjunctiva, after the acute stage has passed, a weak solution of the sulphate of zinc dropped into the eye a few times daily often proves of service. As an astringent injection it is prescribed in cases of discharges, either acute or chronic, from the genito- urinary passages, such as leucorrhoea. Combined with the acetate of lead in solution, it forms the white lotion of Professor Dick. Digitized by Microsoft® ZINC AND ITS MEDICINAL SALTS 251 Zinci Acetas, which is the active constituent of this lotion, resembles in its actions the sulphate of zinc, but is seldom used as a separate agent. Zinci Cliloridum — Chloeide of Zinc. Prepared by the action of hydrochloric acid on granu- lated zinc. Medicinal Uses. — The chloride of zinc is not given internally. Externally, applied without dilution, it is a powerful caustic, possessing great af&nity for water, and coagu- lating albumin. It is sometimes employed as an appli- cation to unhealthy ulcerations, fistulas, etc. It is a powerful antiseptic and disinfectant, and even in dilute solution is a poison to low forms of life, Burnett's dis- infectant contains 25 grains of chloride of zinc to each fluid drachm. CUPRUM— COPPER. The salt of copper employed in veterinary practice is the sulphate. Cupri Sulphas — Cupeic Sulphate, Sulphate op OopPEE., Blue Stone, Blub Viteiol. Prepared by heating copper with sulphuric acid. Incompatibles. — Alkalies and their carbonates, lime- water, mineral salts (except sulphates), iodides, and most vegetable astringents. General Actions. — The actions of copper resemble those of zinc and silver. Externally it produces no effect on the unbroken skin, Digitized by Microsoft® 252 VETERINARY riJERAPEDTlCS and is not absorbed tberefrom. Applied to wounds, ulcers, and delicate mucous membranes freely, it acts as a caustic. It unites with soluble albuminous substances on the surface, forming insoluble albuminates, condenses the structures, and constringes the bloodvessels, and hence is an astringent in solutions of moderate strength. Internally, in large doses, it acts as a direct emetic in the dog ; in toxic doses it is an irritant poison, causing gastro-enteritis, etc. In the intestines, given in medicinal doses, it has an astringent eilect. Sulphate of copper is slowly absorbed, and is supposed to possess some tonic effect on the nutrition of the central nervous system. It is excreted by the liver chiefly, also in the urine and saliva. In poisoning by sulphate of copper, the suitable anti- dotes are albuminous substances, such as white of egg, milk, etc., which form insoluble albuminates with the salt. Medicinal Uses. — As an emetic the sulphate of copper is sometimes prescribed in canine practice, in doses of from grs. vi. to grs. x., for acting quickly in cases of narcotic poisons ; but a more reliable agent is found in the hy- podermic injection of apomorphine. As a tonic and astringent it is occasionally prescribed in doses of 3i. for horses, and gr. -J- to grs. ii. for dogs. It is an antidote to phosphorus-poisoning by combining with the element, and rendering it inert. Externally the sulphate of copper is extensively em- ployed as a stimuUmt, astringent, and mild caustic, in cases of exuberant granulations, unhealthy surfaces, ulcers, etc. It, however, possesses no advantages over the nitrate Digitized by Microsoft® ALUMINIUM 253 of silver for such purposes, and the latter agent is pre- ferred by many practitioners. It is a valuable stimulant and astringent in certain affections of the feet of horses, such as canker, etc., and is recommended as a dressing, combined with the sulphate of zinc and iron. As an injection for cases of quittor the following, known as ' Villate's Injection,' is recom- mended by Professor Macqueen : Cupri sulph., gii. ; zinci sulph., §ii. ; acid. acet. dil., gxxxv. ; liq. plumbi diacet., §iv. In cases of foot-rot in sheep, the sulphate of copper is also a useful application in combination with other agents, such as tarry substances, etc. ALUMINIUM. The most important salt of this metal is alumen, or alum. Alumen — Alum, Aluminium and Potassium Sulphate. Prepared from alum schist and sulphate of potassium. Incompatibles . — Alkalies, lime, acetate of lead, mer- cury, and substances containing tannin. General Actions. — Externally. — Alum locally applied is astringent and styptic ; it absorbs water, and if the skin be broken acts as a mild caustic. It coagulates albumin, condenses the tissues, and constringes the bloodvessels. Internally it causes dryness of the pharynx by co- agulating the mucous secretions, of the part, producing a similar effect on the mucous membrane of the siomach and intestines. In large doses it is emetic, irritant, and purgative. It is absorbed into the blood as an albu- minate, and is excreted chiefly by the kidneys. Digitized by Microsoft® 254 VETERINARY THERAPEUTICS Medicinal Uses. — The chief use of alum is as a topical astringejit, in the form of a lotion, for aphthous ulcerated conditions of the mouth ; it is also applied in the form of dry powder to indolent surfaces with exuberant granula- tions. It is sometimes prescribed internally in cases of hffimorrhage from the kidneys, with the idea that during its excretion the form of albuminate is redissolved, and that the salt will have a styptic effect. Alum is frequently administered to cows to arrest the secretion of milk, when it is desired to stall-feed them. In cases of emergency alum may be employed in strong solution as a styptic. Sub-Geoup II. FERRUM— IRON AND ITS MEDICINAL SALTS. (1) IMMEDIATE LOCAL ACTION. Externally the soluble preparations of iron, such as the persalts, act as astringents and constringents when applied to the broken skin or to mucous surfaces. They coagulate the albuminous tissues and the blood, contract the bloodvessels of the part by compressing the tissues, and thus act as hcemostatics or styptics. Internally the salts of iron have an astringent effect on the mucous membrane of the mouth and contiguous parts. In the stomach all the salts are converted into the chloride, thus differing from those of some other metals which combine with the acid albuminates. If the agent be administered in excess, or if the organ be empty, the digestive fluid is decomposed, and the iron acts as an irritant and astriiigent to the mucous membrane. In the duodenum iron is converted into an alkaline Digitized by Microsoft® IRON AND ITS MEDICINAL SALTS 255 albuminate, and is absorbed in this form, the unabsorbed portion being excreted as the sulphide. (2) ACTION ON THE BLOOD. The preparations of iron have important effects on the blood, acting on the red corpuscles, increasing their number, and the amount of haemoglobin present, being combined with the latter. Iron enters the circulation very slowly, being absorbed along the alimentary canal as the chloride and alkaline albuminate. There is a difference of opinion among authorities as to the manner in which iron is absorbed into the blood. Evidently but a small amount is absorbed, as a large proportion is excreted with the fseces, and if it is injected into the blood much of it passes away in the urine. As the result of experiments, it is stated that in health iron does not increase the number of red corpuscles, but that it does produce this effect in cases of anaemia. Ac- cording to Dr. Wood, iron increases the ozonizing power of the red corpuscles, and is also a stimulant to the source which produces them, thus acting as a hamatinic or blood tonic. (3) SPECIFIC ACTION. The specific action of iron is on the red corpuscles of the blood, and it is said that the temperature is slightly raised as the result of the increased oxidation. (4) EBMOTE LOCAL ACTION. Iron is excreted chiefly by the whole length of the intestines, also by the liver, kidneys, skin, and saliva, and the various mucous surfaces. It possesses remote astringent effects, which are of importance. On the Bowels. — It causes constipation ; certain salts, such as the perchloride, having greater astringent effects Digitized by Microsoft® 256 VETERINARY THERAPEUTICS than others. It gives a characteristic black appearance to the faeces, due to the conversion of the metal into the sulphide and tannate, resulting from the action of the food and sulphuretted hydrogen of the intestines. On the Kidneys. — It is excreted by the cells, not by the glomeruli ; it reduces the volume of urine, but increases the amount of urea and other solids, and the acidity of the excretion. It acts as a remote astringent to the mucous surfaces, and as a haemostatic. Incompatibles of Preparations of Iron. — Alkalies and their carbonates, lime-water, magnesia and its carbonate, tannic and gallic acids, all astringent infusions, such as those of digitalis, cinchona, etc. GENERAL VIEW OF THE DIFFERENT PREPARA- TIONS OF IRON. For convenience of description we may classify the preparations of iron as follows : 1. Those possessing the Haematinic Actions of Iron, with but little Astringency. Examples. — • The oxides and carbonates, comprising ferrum redactum, ferri carbonas saccharata, liquor ferri dialysatus, ferri peroxidum hydratum. All these preparations possess the haematinic action of iron, with but little astringency, and are hence employed in cases where we wish to avoid an astringent effect on the bowels, or any tendency to interfere with the pro- cess of digestion. The question of the solubility in water of an iron salt is not one of importance as regards absorption, as the solid preparations become soluble in the stomach. Digitized by Microsoft® IRON AND ITS MEDICINAL SALTS 267 Ferrum Redactum — Eeduced Iron, Metallic Ieon, WITH A VARIABLE AMOUNT OF OxiDE. Prepared by adding a dilute solution of ammonia to a dilute solution of the perchloride, drying the precipi- tate, and exposing it at a white heat to the action of hydrogen. Medicinal Uses. — This preparation is the least astrin- gent of the iron salts, and is employed in canine practice in cases of anaemia in delicate dogs, and in convalescence from debilitating affections, in doses of from 2 grains to 5 grains. It does not derange digestion or cause con- stipation, and is administered in the form of pills twice daily. Ferri Carbonas Saccharata — Sacchaeated Caebonate op Ieon. Prepared by adding a solution of carbonate of ammo- nium to one of sulphate of iron, and rubbing the. precipi- tate with sugar. The sugar prevents the oxidation of the carbonate. Medicinal Uses. — This is also a mild preparation of iron, and is prescribed in canine practice in doses of from 6 grains to 20 grains in the form of pills. Liquor Ferri Dialysatus — Solution op Dialtsbd Ieon. Prepared by dissolving ferric hydrate, freshly prepared, in a strong solution of the perchloride of iron, and wash- ing with water in a dialyser to remove acidulous matter. 100 grains contain 6 grains of iron. Doses. — Horses, §ss. to gi. ; dogs, iii^x. to iTl_xxx. Medicinal Uses. — This is a very useful preparation of iron, and is extensively employed as a general tonic, com- 17 Digitized by Microsoft® 258 VETERINARY THERAPEUTICS bined with quinine. It does not produce the irritating or astringent effects of the sulphate of iron, and can be prescribed in cases where the latter would be inadmis- sible. Ferri Peroxidirm Hydratum— Pbeoxidb ob Sesqui- OXIDB OF IeON. Prepared by precipitating a diluted solution of the per- sulphate of iron with solution of soda and drying. Medicinal Uses. — The chief use of this salt is as an antidote to poisoning by arsenic. It should be freshly prepared in a soluble form, and in cases of emergency is best made by mixing three ounces of the solution of per- chloride of iron with one ounce of carbonate of soda, or with solution of ammonia, if the latter is not at hand. It converts the arsenious acid into an insoluble compound, which is a basic arsenite of variable constitution. As it requires twelve parts to neutralize one of arsenious acid, the preparation should be administered in large amounts every five or ten minutes, such as half-ounce doses to the dog and an indefinite quantity to the horse, followed up by doses of magnesia. 2. Preparations of Iron characterized by their Corrugating and Astringent Action. These comprise the compounds with the mineral acids, such as the sulphate of iron and the liquor ferri per- chloridi with its medicinal preparations. Ferri Sulphas — Sulphate of Ieon, Feeeous Sulphate, Geebn Viteiol, Ooppbeas. Prepared by dissolving iron wire in sulphuric acid and water, crystallizing, and drying. Digitized by Microsoft® IRON AND ITS MEDICINAL SALTS 259 Ferri Sulphas Ezsi(»;ata. Prepared by heating the sulphate to 212° Fah., remov- ing six-sevenths of its water and powdering ; 2^ grains are equal to about 4 grains of the crystalline sulphate. Doses. — Horses, 3ss. to ^ii- ', cattle, 5i- to §iv. ; dogs, gr. i. to grs. v. repeated twice daily. The dried sulphate is prescribed in half the above doses, and is preferred in consequence of its convenient form for dispensing. Medicinal Uses.— This salt is extensively employed in veterinary practice as a mineral tonic, but, in consequence of its astringency and liability to irritate the gastric mucous membrane, certain precautions are necessary in prescribing it, and these will also apply to the prepara- tions of the perchloride presently to be noticed : (1) That moderate doses should be given, so as not to disorder digestion. (2) That these preparations should not be employed when gastric derangement is present. (3) That they must be prescribed either along with the food, or administered after feeding. (4) That it is of advantage to combine them with laxatives, such as small doses of sulphate of magnesia or sulphate of soda, in order to avoid their constipating effects. The sulphate of iron is prescribed as a general tonic in nasal gleet accompanied by a debilitated condition of the system, being combined with arsenic and bitter tonics, such as nux vomica, in such cases. It is believed to act as a vermicide, and is hence employed for the de- struction of intestinal parasites in combination with other remedies. It is also prescribed in cases of diabetes insipidus, in Digitized by Microsoft® 260 VETERINARY THERAPEUTICS combination with the iodide of potassium and gentian. As a hamatinic it is useful in cases of purpura haemorrha- gica, combined with the chlorate of potash. In convalescence from debilitating affections, such as influenza, it is prescribed with vegetable tonics, but we often find that the bland forms of iron succeed better in cases of this kind, such as dialysed iron, combined with quinine. In canine practice the milder forms of iron are preferred, such as'the saccharated carbonate. Externally the sulphate of iron is used as an astringent preparation in combination with other astringents of a similar nature, as previously mentioned. It also acts as a disinfectant, and mixed with sulphates of lime and alumina, it forms Tuson's Disinfectant Powder, which gives off, when moistened, sulphurous anhydride. Liquor Ferri Perchloridi Fortior — Steong Solution OF Peechloeide op Ieon. Pre]oared by dissolving iron wire in hydrochloric acid and water, adding hydrochloric acid, pouring into nitric acid, evaporating, and diluting. (a) LicLUor Ferri Perchloridi — Medicinal Solution of Perchloride of Iron. Prepared by adding one part of the strong solution to three of water. Doses. — Horses and cattle, ^ss. to gi. ; dogs, v]_y. to n|_xx, given properly diluted. (6) Tinctura Ferri Perchloridi — Tincture of Perchloride of Iron, Tincture of Steel. Prepared by mixing one part of the strong solution with one of spirit and two of water. Doses. — Same as the medicinal solution of the per- chloride. Digitized by Microsoft® inON AND ITS MEDICINAL SALTS 261 Medicinal Uses. — The stroDg solution of the perchlor- ide is not used internally, but externally acts as a power- ful styptic. It possesses, however, a very corrosive action on the tissues, and is hence only to be employed in cases of severe hsemorrhage, such as may occur in wounds of the feet, etc., where its action will not be productive of serious damage to the parts. The medicinal solutions of the perchloride and the tincture are extensively employed as hamatinics and general tonics. In consequence of their irritant and astringent actions, they must be given properly diluted and in suitable doses, so as not to irritate the mouth, interfere with digestion, or cause constipation of the bowels. Some horses possess individual peculiarities to the action of astringent preparations of iron, which even in moderate doses cause interference with digestion. In such cases the milder preparations should be employed. In cases of purpura, the preparations of the perchloride produce beneficial results, and are prescribed with' the chlorate of potash or the oil of turpentine. In cases of hsemorrhage from the stomach, bowels, kidneys or bladder, the preparations of the perchloride are prescribed with benefit as astringents. In cases of erysipelas, frequently repeated doses of the perchloride are highly recommended. In anamic, debilitated patients, with a relaxed condi- tion of the mucous membrane of the alimentary canal, moderate doses of the perchloride, judiciously admin- istered, are useful in producing a tonic effect on this membrane, besides improving the quality of the blood and exerting a beneficial influence on the tissues. In cases of chronic affections of the kidneys the prepara- tions of the perchloride are sometimes prescribed as chalybeate diuretics, also in cases of hsemorrhage from Digitized by Microsoft® 262 VETERINARY THERAPEUTICS the kidneys or bladder, and as remote astringents in cases of chronic discharges from the genito-urinary mucous membrane, such as leucorrhoea. Externally the chief use of the perchloride is as a powerful styjytic. It contracts the bloodvessels and con- denses the tissues, besides causing the blood to form a firm clot on the surface of the wound. In consequence of its corrugating and irritant action on wounds, it should not be used except in cases where the hsemorrhage cannot be otherwise arrested. In cases of flooding of the uterus after delivery, the injection of a solution of the perchloride is highly recom- mended in the proportion of four ounces of the medicinal preparation to twelve ounces of water, which is to be slowly injected into the uterus with a long tube, a free outlet of the fluid being allowed, and the introduction of air avoided. 3. Compounds of Iron with. Other Active Bodies. These include ferri iodidum, ferri arsenias, ferri phos- phas, and ferri et quininse citratis. These preparations are intended to combine the hsema- tinio and tonic properties of iron with the specific action of the constituents with which they are combined. Ferri Iodidum — Iodide of Iron. Prepared from iodine, iron wire, and distilled water, heated together ; the solution, being filtered and evapo- rated, is prescribed in cases of diabetes insipidus in horses, also in nasal gleet, in glandular enlargements, and as a general tonic in the treatment of scrofulous diseases. Doses. — Same as the sulphate. Ferri Arsenias — Aeseniatb of Ieon. Prepared by mixing arseniate of sodium, sulphate of iron, and bicarbonate of sodium together. Digitized by Microsoft® IRON AND ITS MEDICINAL SALTS 263 This preparation is sometimes prescribed in treating certain forms of skin affections, such as psoriasis, chronic eczema, etc., in doses of grs. v. to grs. x. for horses, and tV to i gr- for dogs. Ferri Phosphas — Phosphate of Ieon. Prepared from phosphate of sodium, sulphate of iron, and bicarbonate of sodium. This salt is chiefly used in canine practice, in cases of rickets, and also in dogs recovering from distemper and other debilitating affections, in doses of from grs. iv. to grs. viii. It is conveniently administered in the form of Parrish's Syrupus Ferri Phosphatis Comp., which con- tains in each drachm ^ grain of phosphate of iron and A grain of phosphate of calcium, with small amounts of the phosphates of potassium and sodium. Easton's syrup is also a useful preparation, consisting of 1 grain of phosphate of iron, 1 grain of phosphate of quinine, and -^^ grain of strychnine in each fluid drachm, this quantity being the average dose for the dog, repeated twice daily. Ferri et Quininae Citras — Gitbatb of Ieon and Quinine. A preparation of citrate of iron and quinine, containing 16 per cent, of quinine, is prescribed in canine practice, in doses of from grs. iv. to grs. x. ; as a general tonic it combines the actions of both agents. Sub-Geoup III. HYDEAEGYKUM— MERCURY. All salts and preparations of mercury are derived directly or indirectly from the metal itself. Digitized by Microsoft® 264 VETERINARY THERAPEUTICS GENBEAL ACTIONS. (1) IMMEDIATE LOCAL ACTION. Externally. — Most preparations of mercury have but little action on the unbroken skin unless apphed for some time, but certain salts possess marked caustic and counter-irritant properties, such as the solution of the nitrate and the biniodide ; all are capable of absorption from the skin. On mucous surfaces and on abraded tissues there are, however, definite effects produced, de- pending on the preparation employed. Thus, some, such as the red oxide, the diluted nitrate, and weak solutions of the perchloride, are astringents, and stimulants locally. Others, such as stronger solutions of the perchloride and the nitrate, are caustics. All preparations are antiseptics and disinfectants, es- pecially the perchloride. Internally the local action of mercury also depends on the preparation employed and its strength. All pre- parations produce certain effects on the mouth, gums, and salivary glands, resulting in salivation when ad- ministered in full amount and for a period of time, these effects, however, being due to the excretion of the drug from the system, and not to the local action. In the stornach the salts of mercury combine with the chloride of sodium present in the secretions, and become converted into a double chloride of sodium and mercury ; this, again, combines with albumin, forming a complex substance. It is precipitated at first, then becomes soluble in excess of chloride of sodium and albumin, and is in this form diffusible and easily absorbed. In large or concentrated doses an irritant effect is produced in the stomach. In the duodenuin an irritant action is Digitized by Microsoft® MERCURY AND ITS PREPARATIONS 265 produced, resulting in purgation; that is, speaking of certain preparations. This effect is probably a local one, the intestinal glands being stimulated to increased secretion, and the mucous membrane irritated so as to produce an increased flow of fluid from the vessels, with more active peristalsis. The contents of the small intestines are thus evacuated, along with any bile present in the duodenum. (2) ACTION ON THE BLOOD. Only a small amount of a medicinal dose enters the blood from the intestines, as the major portion passes off with the faeces as a sulphide, unless combined with opium, which delays its passage through the bowel. The combination which mercury forms in the stomach and intestines becomes decomposed on entering the blood by combining with oxygen and albumin, an oxy-albuminate of mercury being the result. We are not aware of any direct action of mercury on the blood, but large doses cause impoverishment of both plasma and corpuscles, resulting in a watery con- dition of the blood and a diminished power of coagula- tion. (3) SPECIFIC ACTION. The specific action of mercury is not exerted through the blood, but by a direct action on the tissues them- selves. It leaves the blood quickly and enters the tissues, being slowly excreted therefrom. It is found most abundantly in the liver, but remains in every organ of the body, and a point worthy of note is that even in cases of chronic poisoning by the drug no definite anatomical changes have been found in the organs con- taining it. The influence of mercury on nutrition is supposed to depend on its power of interference with Digitized by Microsoft® 266 VETERINARY THERAPEUTICS the growth or hfe of germinal cells, and this may be termed an alterative influence. When mercury is administered in small doses for a considerable period, a condition termed mercurialisvi or hydrargyrism is produced, characterized by the following train of symptoms, viz., salivation, tenderness of the mouth and gums, impaired appetite, dyspepsia, anaemia, and in some instances eczematous eruptions and bone affections. (4) EBMOTE LOCAL ACTION. Mercury is removed from the system by all the secre- tions, the chief channel of escape being the kidneys. During its excretion it stimulates many of the glands, especially the salivary glands, acting as a powerful siala- gogue. It has only a slight diaphoretic effect, and does not increase the volume of the urine, but combined with diuretics, such as digitalis, it assists their action. It is excreted in the faeces as the sulphide, derived partly from a considerable amount of the unabsorbed portion of the dose administered, and partly from the portion excreted from the liver, pancreas and intestinal glands. It is apparent that we cannot place any therapeutic value on the remote local action of this drug. The Actions and Medicinal Uses of the Different Pre- parations of Mercury. — For convenience of description it will be of advantage to classify the preparations of mercury as follows : ' 1. Metallic Mercury and its Preparations. 2. The Perohloride of Mercury and its Preparations. 3. The Subchloride of Mercury and its Preparations. 4. A Complex Group, consistitig of the Oxides, Iodides, Aminoniated Mercury. 5. Acid Solution of Nitrate of Mercury. Digitized by Microsoft® MERCURY AND ITS PREPARATIONS 267 1. Metallic Mercury and its Preparations. Metallic mercury is not given internally except in the finely divided form in which it exists in the pilula hydrargyri and the hydrargyrum cum creta. Pilula Hydrargyri — Blue Pill. Prepared by mixing two parts mercury, three of confec- tion of roses, and one of liquorice. Medicinal Uses. — Blue pill is sometimes employed in canine practice as a purgative and indirect cholagogue, in doses of from grs. iii. to grs. v., generally combined with a similar amount of the compound colocynth and hyoscy- amus pill. Hydrargyrum cum Creta — Mbecuey with Chalk, Geey Powdee. Prepared by triturating together one part of mercury with three of prepared chalk. Medicinal Uses. — In cases of bilious indigestion, with diarrhoea, occurring in young calves and foals, the hy- drargyrum cum creta is useful as a laxative antacid and alterative in small doses, such as from grs. v. to grs. xv. repeated twice daily. In canine practice small doses are useful in dyspepsia due to hepatic irregularities, especi- ally if there is gastric irritability. It is also useful in cases of diarrhoea in young dogs depending on indiges- tion, in which the food acts as an irritant in the ali- mentary canal. It restores the natural colour to the faeces, and reduces the irritability of the intestinal mucous membrane. For such purposes it should be administered in small repeated doses, from gr. ^ to grs. iii., according to the size of the patients. Digitized by Microsoft® 268 VETERINARY THERAPEUTICS Unguentum Hydrargyri — Blub Ointment. Prepared by mixing mercury with lard and suet in the proportion of one to two. Uses. — The blue ointment is not employed in veterinary practice to produce constitutional effects. If applied with friction it produces vesication, and in sufficient amount becomes absorbed, producing the specific effects of mercury in the system. For this reason the ointment has to be cautiously applied. It is sometimes employed as an absorbent application to reduce swelling of joints, and is useful in some cases of obstinate jJSoHasts. Linimentum Hydrargyri— Mbecueial Liniment. Oleatum Hydrargyri — Olbatb op Meeouey. Both these preparations possess similar actions, being diffusible, penetrating, absorbent agents. The liniment is prepared by mixing equal parts of mercurial ointment, solution of amruonia, and camphor liniment together. The oleate is a mixture of the yellow oxide of mercury in oleic acid. They may be used in cases of persistent scaly skin diseases, in tinea and favus, and as absorbent applications to enlarged glands, and to cases of indura- tion of the mammary gland in cattle. 2. Hydrargyri Percliloridum — Pbechloeide op Mee- CUEY, COEEOSIVE SuBLIMATE, MbECUEIC ChLOEIDE. Prepared by triturating a mixture of persulphate of mercury, chloride of sodium, and black oxide of man- ganese together and subliming. Incompatibles . — Alkalies and their carbonates, iodide of potassium, lime-water, nitrate of silver, acetate of lead, albumin, soaps. Actions and Uses. — Corrosive sublimate, containing Digitized by Microsoft® MERCURY AND ITS PREPARATIONS 269, twice as much chlorine as calomel and being very soluble, acts as an irritant corrosive poison in sufficient quantities, hence it is of importance to distinguish between the two salts of mercury in prescribing and dispensing. If administered in strong solution it causes gastro- enteritis, producing a bluish-gray appearance of the ali- mentary mucous membrane, with patches of inflammation and sloughing in severe cases. It is not prescribed internally. The Antidotes consist of the free administration of albumin, which forms an insoluble mercuric albuminate. For such purposes eggs, flour, milk, etc., should be freely given. Externally strong solutions of corrosive sublimate act as caustics and escharotics. The most important use of corrosive sublimate is founded on its antiseptic pro- perties. It is one of the most active of antiseptic agents, and in the proportion of 1 part to 1,000 of water is capable of destroying bacilli and their spores. It is ex- tensively employed as an antiseptic dressing for wounds in the proportions stated, and also used to render cotton- wool or wood-wool aseptic for surgical uses. The danger of absorption from strong applications of the perchloride must not be lost sight of. 3. Hydrargyri Subchloridum— Subchloeide of Meecuby, Calomel, Meecubous Chlobide. Prepared by triturating a mixture of persulphate of mercury, mercury, and chloride of sodium, subliming, and washing. Doses. — As an alterative : Horses and cattle, grs. x. to grs. XX. ; dogs, gr. i. to grs. ii. As a purgative and cholagogzie : Horses, Ji., generally combined with aloes ; cattle, 5i. to Jii., combined with other purgatives ; dogs, grs. ii. to grs. v., combined with jalap or colooynth. Digitized by Microsoft® 270 VETERINARY THERAPEUTICS Actions and Uses. — Calomel, being very insoluble, possesses mild actions compared with other salts of mer- cury. It must be rendered soluble before being-absorbed, consequently the effects will depend to a certain extent on the amount which is made soluble. In proper doses it is a purgative in all animals, besides acting as an indirect cholagogue and a diuretic. Its purgative action is a purely local one, probably by stimulating the in- testinal glands and irritating the mucous membrane, causing the outpouring of fluid from the vessels. The cholagogue action is one on which some difference of opinion exists. Experimentally, it has been demon- strated that calomel does not increase the secretion of bile, but that corrosive sublimate possesses this action. In purgative doses it is believed that calomel acts as an indirect cholagogue by clearing away the bile present in the duodenum, and preventing its reabsorption. However, some authorities state, as the result of chnical experience, that in some affections calomel does increase the flow of bile, as small doses of the drug restore the colour to the f seces which had become pale as the result of liver derangement. Calomel is a very useful agent as a cathartic and in- direct cholagogue in cases where such a combination is desirable, such as congestion of the portal system and liver. It assists the action of other purgatives with which it is combined, and is thus employed in all cases where a full purgative effect is desired, such as tetanus, brain affections, lymphangitis, etc. In former times calomel was extensively employed as an alterative and febrifuge in all febrile and inflammatory affections, either combined with opium or otherwise ; in the present day, however, in consequence of our improved knowledge of the pathology of these affections, we avoid agents likely to Digitized by Microsoft® MERCUUY AND ITS PREPARATIONS 271 depress the patient, of which calomel is one. In altera- tive doses it is sometimes prescribed in cases of gastric irritation, intestinal catarrh, and bilious diarrhcEa, but the hydrargyrum cum creta is to be preferred for such purposes. Externally calomel is desicoant, stimulant, and astrin- gent. In the form of ointment (1 to 8) it is employed to allay the severe itching of certain skin affections, such as eczema, pityriasis, etc. In that affection of the frog of the horse's foot termed ' thrush,' calomel is a most useful agent, combined with equal parts of iodoform, and applied thoroughly to the cleft of the frog, the part being kept as dry as possible. 4. The Oxides, Iodides, and Ammonio-Chloride of Mercury. There are two oxides of mercury, viz. : Hydrargyri Suboxidum — Black Oxide of Mbeouey. Hydrargyri Oxidum Rubrum — Ebd Oxide of Meb- . cuEY, Ebd Precipitate. Both these salts possess similar actions, viz., stimulant and astringent, when locally applied ; they are not used internally. A modification of the red oxide, but of similar composition, is the yellow oxide, which is non-crystal- line. The therapeutic value of these oxides consists of their presence in two useful lotions, viz. : Lotio Hydrargyri Nigra— Black Wash. Prepared by mixing 30 grains of calomel in 10 ounces of lime-water (1 to 146), the black oxide of mercury being precipitated. Digitized by Microsoft® 272 VETERINARY THERAPEUTICS Lotio HydrargyrI Flava— Yellow Wash. Prepared by mixing 18 grains of corrosive sublimate with 10 ounces of lime-water (1 to 243), the yellow oxide of mercury being precipitated. Both these lotions are used as applications to ulcers, unhealthy surfaces, chronic scaly skin eruptions, etc., the yellow wash being the most active. In collar and saddle galls, which are slow in healing, the yellow wash is a useful stimulant and astringent. Hydrargyri lodidum Rubrum — Bed Iodide of Mbbcuby, Biniodide op Meecuet. Prepared by mixing hot solutions of perchloride of mercury and iodide of potassium, washing and drying the precipitate.' Actions and Uses. — The presence of iodine in this salt renders it more soluble, and hence more quickly ab- sorbed. It is seldom prescribed internally, except in the combination with arsenic known as the liquor arsenii et hydrargyri iodidi, or Donovan's solution, prepared by dis- solving equal parts of iodide of arsenic and red iodide of mercury in water, in the proportion of 1 per cent, of each salt. This is recommended as an alterative in chronic scaly skin affections, in doses of Ji. to gii. for horses, and Tl|^x. to Tl\xxx. for dogs, repeated twice daily. Externally the red iodide of mercury is extensively employed as a counter-irritant and absorbent in cases of diseases of joints and the various forms of exostoses. Applied sufficiently strong, it penetrates deeply, and acts as a suppurant. It is used in the form of an ointment in the proportion of 1 part to 8 of the basis, which should be preferably ■ of lanoline. This increases greatly the penetrating and absorbing powers of the agent. Digitized by Microsoft® MERCURY AND ITS PREPARATIONS 273 When it is desired to produce severe counter-irritation, equal parts of the ointment of the red iodide and of can- tharides are mixed together. A very severe blister is prepared by a mixture of the red iodide of mercury and iodide of potassium, dissolved in methylated spirit along with cantharides. For the purposes of a slow absorbent application in cases of capped hocks, etc., it is recom- mended to dissolve 1 drachm of the red iodide with a sufficiency of iodide of potassium in 12 ozs. of water, and to apply this daily until the part gets scaly and tender, when it is discontinued for a time and then reapplied. Hydrargyrum Atnmoniatum — Ammoniated Meecuey, White Pbeoipitate. Prepared by precipitating a solution of perchloride of mercury with diluted solution of ammonia, washing and drying. Medicinal Uses. — It is not used internally. Externally it is employed as a stimulant application to chronic skin diseases, especially to those troublesome affections of the posterior portion of the knee and anterior por- tion of the hock known as mallenders and sallenders in horses, in the proportion of 1 to 10 of simple oint- ment. It often succeeds for this purpose when other agents fail. (5) Liq. Hydrargyri Nitratis Acidus — Acid Solution of Nitrate of Mercury. Prepared by dissolving mercury in nitric acid and water, and boiling. Unguentum Hydrargyri Nitratis — Citeine Ointment. Prepared by mixing a hot solution of mercury, nitric acid, lard, and olive oil together. This ointment, mixed with 2 parts of soft paraffin, forms the unguentum hy- drargyri nitratis dilutum, or dilute citrine ointment. 18 Digitized by Microsoft® ^74 VETERINARY THERAPEUTtCS Actions and Uses. — The acid solution of the nitrate of mercury is a strong caustic, and may be employed for this purpose in malignant growths, canker in the feet of horses, etc. The dilute citrine ointment is very useful in cases of eczema in dogs, especially in the stage of desquamation ; its ef&cacy is greatly increased by the addition of creolin, combined with lanoline. In irritable and discharging conditions of the eyelids, with chronic inflammation and ulceration of the hair follicles, a careful application of weak citrine ointment is productive of much benefit. In chronic cases of grease in horses' heels, citrine ointment is a very useful application, and in deep fissures of the same parts, with little tendency to heal, the addition of iodoform to this ointment often produces beneficial results. Mercury and Zinc Cyanide — A double Cyanide op Mbecukt and Zinc. This has been strongly recommended by Sir Joseph Lister as an antiseptic dressing for wounds; and is best prepared in the form of an antiseptic gauze, which should be dipped immediately before use into a 1 to 4,000 solu- tion of perchloride of mercury. Experiments with this salt have demonstrated that half the strength is requisite to prevent putrefaction in serum and corpuscles as com- pared with corrosive sublimate. It is stated that the double cyanide of mercury and zinc is feeble as a germi- cide, but admirable in preventing the growth of microbes ; hence it is recommended to treat the gauze before using with a solution of corrosive sublimate or carbolic acid. Sir Joseph Lister states that this salt tends to cause healing by first intention, and that granulating wounds heal in a satisfactory manner by a gradual process of cicatrization, while the dressing is quite unirritating to the skin. Digitized by Microsoft® PHOSPHORUS 215 Sub-Geoup IV. PHOSPHORUS. A non-metallic element obtained from bones. The chief therapeutic interest in this substance depends on the hypophosphites of sodium and calcium which are derived from it, and possessing similar actions, are the forms in which it is usually prescribed. (1) IMMEDIATE LOCAL 'ACTION. Phosphorus is a local irritant and caustic," both ex- ternally and internally. In toxic doses it causes gastro- enteritis, with intense thirst, and in dogs produces vomit- ing of a dark green or black substance, with the odour of garlic, and sometimes phosphorescent. As a poison it is peculiar in the comparative slowness of its action, and the variable duration of its effects in acute cases. It causes catarrh of the small biliary ducts, and as a consequence jaundice, and generally diarrhoea ; also a fall of temperature and fatty degeneration of different organs and tissues. Post-mortem examination shows general inflammation of the glandular structures of the stomach and intestines, the mucous membrane being thickened and of a whitish colour. The antidotes are oil, of turpentine, which forms an inert compound with phosphorus, and sulphate of copper, which forms an insoluble phosphide. Milk, oil, eggs, etc., should be avoided, as they render the poison more soluble. (2) ACTION ON THE BLOOD. Phosphorus enters the blood, and is partly oxidized into phosphorous or phosphoric acid, by the oxygen de- rived from the red corpuscles. Digitized by Microsoft® 276 VETERINARY THERAPEUTICS (3) SPECIFIC ACTION. It acts specially on the glandular and nervous systems. It can be traced in the tissues in its unchanged form, as it is only partly oxidized in the blood. The agent has special effects on metabolism, especially when given in full doses. These consist of increase of the nitrogenous products, such as urea, etc., a reduction of the formation of glycogen in the liver, a diminution of oxidation, and of the volume of oxygen absorbed, resulting in fatty de- generation of the epithelial, glandular, and muscular tis- sues of the body. In small doses, continued for a length of time, phosphorus has a special effect on the structure of bone, which has been proved experimentally, convert- ing the spongy texture into firm, compact substance without altering its chemical composition. (4) BEMOTE LOCAL ACTION. Phosphorus is excreted by the kidneys and lungs partly as phosphorous acid and partly unchanged, but not as phosphates. Medicinal Uses. — As the hypophosphites of calcium and sodium act very much the same as phosphorus, but are not irritant, they are preferred for therapeutical pur- poses. As tmiics and alteratives they are prescribed in cases of general debility and anaemia in foals and dogs ; they increase appetite and digestion, and overcome weak- ness. They are also prescribed in cases of rickets, bone softening, and chronic malnutrition in doses of 10 to 20 grs. for foals and 1 to 5 grs. for dogs, repeated twice daily. The Phosphate of Calcium, which conjoins the actions of calcium and phosphorus, is prescribed in cases of de- bility, malnutrition, and rickets, and is sometimes com- bined with iron. Doses. — Horses, 3ii. to 3iv. ; dogs, grs. v. to grs. x. Digitized by Microsoft® A RSENIC AND ITS PREP A RA TIONS 277 Phosphate of Sodium. — This salt acts as a moderate eholagogue, increasing directly the secretion of bile ; in full doses it is a saline purgative. AKSENIUM— ARSENIC. All preparations of this agent are derived from white arsenic. Acidum Arseniosum — Aesenious Acid. Aesbnicum Album — White Aesenic. Source. — Obtained by roasting arsenical ores, and puri- fied by sublimation. It is an anhydride and not a true acid. Incompatibles. — Salts of iron, magnesium, lime-water. Doses. — Horses and cattle, grs. ii. to grs. v. ; sheep, grs. ss. to grs. ii. ; dogs, -^-^ to J^ gr. , administered either along with the food or immediately afterwards, repeated twice daily. Liquor Arsenicalis — Fowler's Solution. Prepared by boiling arsenious acid and carbonate of potash in water, and colouring with compound tincture of lavender ; contains about 4^ grs. to the ounce (1 to 100). The carbonate of potash renders the arsenic soluble. Doses. — Horses and cattle, 3ii- to ^i- ! dogs, TTl^ii. to IT^viii. Liquor Arsenii et Hydrargyri lodidi— Donovan's Solution (see IIydrargyrii,m, p. 272). GBNBEAL ACTIONS. (1) immediate local action. Externally. — -Arsenious acid is irritant, caustic, and antiseptic. It is not absorbed from the unbroken skin, Digitized by Microsoft® 278 VETERINARY THERAPEUTICS but on wounds, ulcers^ etc., it excites very active inflam- mation, and is liable to become absorbed, unless, indeed, the process of inflammation is so severe that the part loses the power of absorption. It is an escharotic, slowly corroding and destroying the tissues with which it comes in contact. Internally. — In medicinal doses, on reaching the stomach, it does not form an albuminate like other mem- bers of this group, but is changed into a soluble form and absorbed into the blood. It is believed that if food be present the drug is absorbed by the lacteals and con- veyed to the blood, while if the stomach be empty, it is absorbed by the veins and passes on to the liver. If stimulates the gastric nerves and vessels, increases the power of digestion, and sharpens the appetite. In large doses it causes irritation of the gastric and intestinal mucous membrane, producing nausea and diarrhoea, while toxic doses are corrosive and irritant ; these effects, however, being also due to the excretion of the agent as well as to the immediate local action. (2) ACTION ON THE 3L00D. Arsenic is quickly absorbed from the alimentary canal, also from any mucous, serous, or skin abraded surface. We are not aware of any special effect of the agent on the blood ;• it can be detected in this fluid as well as in most organs of the body. (3) SPECIFIC ACTIONS. Arsenic enters all tissues and organs ; it does not form albuminates therein, and is more quickly eliminated than other metals. It manifests a special affinity for the mucous membrane of the alimentary canal, producing effects thereon, no matter by what channel it enters the Digitized by Microsoft® ARSENIC AND ITS PREPARATIONS 279 system. It also produces special effects on the nervous system, on metabolism, and on the skin. Medicinal doses, as already mentioned, act as stimulants to the alimentary mucous membrane ; large doses cause irrita- tion, while a toxic dose acts as an acute irritant poison. It causes gastro-enteritis in all animals, the post-mortem appearances varying with the severity and duration of the ease. There is generally acute inflarnmation of the stomach, often in patches ; sometimes spots of ecchymosis are present, and less commonly ulcerations. Inflammation of the lower portion of the oesophagus, also of the intestines, may be present. Mr. Gresswell (' Manual of Equine Medicine ') records some important cases of arsenical poisoning in horses in which the post-mortem examinations showed several small patches of redness in the cuticular portion of the stomach, with erosion of the wall in one case, at its junc- tion with the villous portion. The villous portion was intensely inflamed, of a dark brownish-red hue, and covered in parts with a film of coagulated lymph ; patches were blackened, and in some places there was much erosion, while in one case there were two almost com- plete perforations through the walls. The small and large intestines were acutely inflamed in patches. An important lesion noted was the presence of inflammation of the endocardium of the left ventricle, with patches of ecchymosis thereon, showing the special effect of arsenic on this membrane. In animals poisoned by arsenic, the carcases usually resist decomposition to a great extent. On the'nervous system arsenic possesses specific effects. It diminishes the sensibility and reflex-irritability of the centres of the spinal cord, and afterwards depresses the motor nerves and muscles, in toxic doses causing genefa,! Digitized by Microsoft® 280 VETERINARY THERAPEUTICS paralysis. Some authorities conclude as a result of their . experiments that sensation and reflex action persist as long, or longer, than voluntary power ; also that arsenic is a protoplasmic poison, destroying the functional activity, first of the central nervous system, next of the nerves, and last of the muscles (Dr. Einger, ' Handbook of Therapeutics '). It is important to remember that in some cases of arsenical poisoning the usual symptoms of gastro-enteritis may be absent, and the animal may die in a state oi pro- found coma, the post-mortem examination not revealing any signs of inflammation of the alimentary mucous membrane. In such cases the chief effect of the poison is on the nervous system. 071 the heart and circulation experiments prove that in toxic doses arsenic arrests the action of the heart by a direct effect on all its structures — nerves, ganglia, and muscle. It lowers the arterial tension, first accelerating and then decreasing the action of the heart, also influ- encing vaso-motor nerves. On the respiratory system it first stimulates slightly the respiratory centre and the pulmonary terminations of the vagi. In toxic doses it paralyzes the respiratory centre. On metabolism it reduces the amount of glycogen in the liver, and interferes with metabolism by diminishing oxidation. The results are, an increased amount of nitrogenous materials in the urine, a rise in temperature, and if the action of the drug be long continued there occurs an excess of the fatty products of albuminous de- composition in the system which are not excreted, and a condition of fatty degeneration of different tissues and organs is brought about. On the shin arsenic possesses a specific action. It pro- Digitized by Microsoft® A RSENIC A NJD ITS PREP A RA TIONS 28 1 ■ duces desquamation of the superficial layer of the skin, and experiments on frogs prove that this effect is. due to a direct action on the skin and the epidermic cells, in which, by a form of stimulation, there is a peculiar destructive change in the metabolism of these cells. In medicinal doses this stimulation of the epidermis is found to occur in cases of chronic scaly skin diseases, and is an action of importance to the therapeutist. We may briefly enumerate the important symptoms of poisoning by arsenic, and will first remark that in the various species of animals, and also in individuals of the same species, the symptoms will vary greatly as regards severity, and the amount of the drug necessary for a toxic dose is not definite, the soluble preparations being most active. In the horse the toxic dose is liable to great variation, which fact has been demonstrated by experiments. In some instances even medicinal doses produce serious effects. All animals acquire a tolerance of it, if the drug be administered regularly, and after a time their systems are enabled to resist the effects of large doses. The severity of a toxic dose will depend to some extent on the amount of food present in the stomach. The period of time which the drug takes before mani- festing acute symptoms in the horse varies from half an hour to three or four hours, and cases are recorded where death occurred within an hour. The symptoms are — violent purging, extreme tenesmus, violent colicky pains, pulse weak, irregular and thready, gradually becoming imperceptible ; respirations greatly accelerated, temperature variable, from 101° to 105° Fahr., extremities cold ; death occurring with a comatose con- dition, or with tetanic spasms. (Mr. Gresswell, ' Manual of Equine Medicine.') Digitized by Microsoft® 282 VETEETNARY THERAPEUTICS Cattle are less susceptible to the action of arsenic, and a longer period elapses before symptoms are developed, in consequence of the arrangement of the stomach, which renders its absorption slow. In cases recorded, poisonous symptoms appeared in twenty hours, consisting of acute abdominal pain, purging, staggering gait, etc. In sheep there are many cases recorded of arsenical poisoning from the use of arsenical dipping mixtures. In such instances it results from too large a proportion of arsenic being present in the dip, and by allowing the sheep to wander over the pastures and to graze thereon : the drippings from the fleece fall on the grass, and thus the drug is taken into the system. It is believed, and experiments bear it out, that arsenical sheep dips are not absorbed through the sound skin. The symptoms recorded are — dulness and nausea, frothing at the mouth, colicky pains, accelerated re- spiration, and in some instances death occurs rather suddenly. In dogs, which are usually very susceptible to the action of arsenic, the symptoms are nausea, vomiting, pain, pulse quick and wiry, purging with dark-coloured evacuations, and convulsions with death in a space of from six to thirty hours. Chronic arsenical poisoning may occur in certain dis- tricts where tin and copper smelting-furnaces are worked, the usual symptoms being indigestion, thirst, swelling of joints, and gradual emaciation. In the horse, cases of both acute and chronic arsenical poisoning have been recorded as the result of the ad- ministration of the drug by the attendants with the idea of improving the condition of the animal, and Mr. Gress- well (' Manual of Equine Medicine ') relates an interest- ing case of this description, in which an irregular pulse, Digitized by Microsoft® A RSENIC A ND ITS PREP A R A TIONS 283 with great distress of breathing during moderate exercise, were the results of repeated small doses of arsenic, con- tinued for a long period. When arsenic is long-continued in medicinal doses, certain symptoms occur which the practitioner should carefully watch for, so as to avoid them by diminishing the amount given, but not by suspending it altogether. These are first noticed in the eyes and stomach, consist- ing of a slight oedematous condition of the eyelids, resulting in slight conjunctivitis, either followed or pre- ceded by irritation of the stomach, evidenced by indiges- tion and diarrhoea ; and in dogs thirst and vomition may occur. The antidotes and treatment of arsenical poisoning consist of the prompt administration of emetics in the dog ; while in all animals the most reliable chemical antidote is the hydrated sesquioxide of iron, which can be prepared in cases of emergency by adding a solution of ammonia to the perchloride of iron solution, washing the precipitate with warm water, and administering it moist in repeated doses at intervals of ten minutes. A mixture of carbonate of soda with a solution of the perchloride acts in a similar manner ; also dialyzed iron — the action of these iron preparations being to convert the arsenic into an inert insoluble substance. Hydrated magnesia, prepared by precipitating a solu- tion of sulphate of magnesia with caustic potash, is also useful in diminishing the solubility of arsenic ; while mechanical antidotes — such as oils, demulcents, milk, etc. have a similar effect, besides reducing the irritation of the gastro-intestinal mucous membrane, the addition of a preparation of opium being of advantage in this respect. In chronic cases, oleaginous laxatives, tonics, and Digitized by Microsoft® 2S4 VETERINARY TflERAPEUTICS diuretics are employed to hasten the ehmination of the poison. (4) EEMOTB LOCAL ACTION. Arsenic is ehminated chiefly in the urine in the form of arsenious acid; also by the gastro-intestinal mucous membrane, the liver, and skin. As previously mentioned, its irritant effects are due to its excretion as well as its immediate local action. Medicinal Uses. — Internally. — As a gastric tonic, arsenic is prescribed in some cases of gastric dyspepsia. It pro- duces beneficial effects by stimulating the nerves and vessels of the stomach, and is administered either along with the food, or immediately after feeding, in the form of the liquor arsenicalis ; and here we may remark that for all purposes this preparation of arsenic is preferable, being more soluble and less liable to cause irritation. The form of dyspepsia in which arsenic is indicated is characterized by excessive peristaltic action of the stomach and intestines, resulting in the passage of imperfectly digested food into the intestines, and the occurrence of purging after feeding. The arsenic may be combined with antacids, and some authorities recom- mend that it be given in small doses shortly before feeding ; but this is rarely necessary. As a general tonic and alterative, or modifier of nutrition, it is prescribed in various affections, such as general debility, anaemia, chronic nasal catarrh, nasal gleet, etc., and in such cases is usually combined with a preparation of iron. In nervous affections — such as chorea, epilepsy, etc.' — • in dogs, its administration is often productive of beneficial results, which are believed to depend partly on its power of diminishing sensibility and reflex irritability of the nerve centres, and partly on its alterative actions, Digitized by Microsoft® ARSENIC AND ITS PREPARATIONS 285 In spasmodic asthma in dogs, and in that affection in horses known as broken ivind, it is a very valuable pallia- tive remedy, and is combined with other agents, such as aconite, digitalis, etc. It is also useful in cases of chronic cough, and in such respiratory affections its beneficial effects must be ascribed to its action on the nerves, as well as its action on the digestive organs, a large proportion of such cases depending on reflex irritability from the stomach. In affections of the skin it is most serviceable in those affecting the more superficial parts, such as psoriasis, and chronic scaly skin eruptions. It is also useful in chronic eczema in dogs, and cases of chronic grease in horses. Its effects in such cases must be ascribed in part to its specific action on the superficial layers of the skin, and also to its action as a general alterative ; but, generally speaking, it is contra-indicated in acute cases. Precautions in the Administration of Arsenic. — As already stated, all patients are not affected alike by medicinal doses of arsenic, so that in prescribing this drug it is always advisable to commence with a minimum dose, and to gradually increase it as the system becomes accustomed to its effects. In some affections a long period of time is required before beneficial effects are produced, and although we should avoid the production of the physiological action of the drug, still, it requires to be pushed to a proper extent, especially in skin affections and nervous disorders. It should be given along with the food, or immediately afterwards, so as to avoid its free contact with the gastric mucous membrane. It is contra-indicated in cases of gastric irritability, and during the acute inflammatory stages of eruptions. Digitized by Microsoft® 286 VETERINARY THERAPEUTICS Externally. — As a caustic and escharotic, arsenic is seldom employed, in consequence of the severity of its action, and the danger of its being absorbed. It is sometimes mixed with corrosive sublimate, a small amount of arsenious acid and the latter being mixed in tissue paper, and introduced into the sinus of a quittor in order to form a slough, and produce a healthy action of the part ; but the use of the knife in such a case gives safer and better results. As an anti-parasitic, arsenic is largely employed in sheep-dips, and vrith proper precautions can be used with safety. The following is a safe dip : Take 2 lb. of arsenious acid, 2 lb. of carbonate of potash, 2 lb. of sublimed sulphur, and 4 lb. of soft soap ; dissolve in 10 gallons of boiling water, and add cold water to make 100 gallons. This will be sufficient to dip about 100 sheep, and the following precautions should be attended to — viz. : The sheep should be kept in the dip about a minute, with the head carefully kept away from the fluid. The animal is then placed on a sparred apparatus over another receptacle, and the wool squeezed as dry as possible with a scraper, especial care being taken not to allow the animal on pasture immediately afterwards. ANTIMONIUM— ANTIMONY. All the medicinal preparations are derived from anti- monium nigrum, black antimony, which is obtained from the native sulphide. The chief preparations in use are : Liquor Antimonii Chloridi — Tbechloeidb of Antimony, BuTTEE OP Antimony. Prepared by dissolving purified black antimony in hydrochloric acid. Digitized by Microaofl® ANTIMONY AND ITS PREPARATIONS 287 Antimonium Tartaratum — Tabtaeatbd Antimony, Taetae Emetic. Prepared by mixing oxide of antimony and acid tar- trate of potassium with water, boiling, evaporating, and crystallizing. THE ACTIONS OP ANTIMONY PEEPAEATIONS. (1) IMMEDIATE LOCAL ACTION. The chloride of antimony is a powerful esckarotic, and unless cautiously applied it produces a sloughing of the part which is not disposed to heal. Tartar emetic, applied to the skin in the form of solution or of ointment, causes an eruption which is first papular and then pustular, and thus acts as a severe counter-irritant. It is absorbed from the broken skin and mucous surfaces. Internally. — In the dog this agent acts as an emetic in doses of one to three grains. This effect is produced both directly and indirectly — directly, by its irritant action on the terminations of the nerves of the stomach ; and indirectly, by stimulating the vomiting centre in the medulla. Its action is slow, fifteen minutes or longer being required. It produces this emetic action when injected into a vein, but more slowly ; and its effects are prolonged, much nausea and depression resulting, showing that the drug is excreted by the gastric mucous membrane. In horses and cattle, except in very large amounts, it produces no effects, and even then only a slight degree of nausea and uneasiness is found to result. (2) ACTION ON THE BLOOD. Antimony enters the blood, and does not comhine with the albumen of the plasma. We are not aware of any action which it produces under this head. Digitized by Microsoft® 288 VETERINARY THERAPEUTICS (3) SPECIFIC ACTION. As already mentioned, it produces no effects in the horse in ordinary amounts. In the dog it produces specific actions as follows : On the heart and circulation it is depressant. It acts directly on all the tissues of the heart, and partly in a reflex manner from the stomach ; it also acts on the vessel walls. On the respiratory system it diminishes and disturbs the respiratory movements. On the nervous system it causes depression, both directly and also through the circulation. On metabolism the effects of antimony resemble those of arsenic and phosphorus, in large amounts causing deficient oxygenation, increase of nitrogenous products, and fatty degeneration of organs. On the skin it acts as a stimulant to the superficial layers, resembling arsenic to a certain extent in this respect. In man it acts as a diaphoretic ; but this effect is not observed in animals. Toxic Effects. — In the horse, except when administered in very large amounts, no appreciable effects are produced. The results of experiments go to prove that this animal resists the action of antimony in a remarkable manner. In a few instances symptoms of nausea and uneasiness are recorded after large doses, the post-mortem appear- ances showing slight softening and vascularity of the intestines, while in some cases no lesions could be dis- covered. The drug is stated to produce more definite actions when administered intravenously, some experi- menters recording purging and salivation, acceleration of the pulse and respirations, as the results of one drachm administered in this manner. In cattle the drug also produces little physiological Digitized by Microsoft® ANTIMONY AND ITS PREPARATIONS 289 effect, the result of the administration of large doses being to cause purgation in some cases. In the dog the drug acts as a powerful depressing emetic, in large doses producing gastro-enteritis, purging, and intense prostration. (4) EBMOTE LOCAL ACTION. Antimony is excreted by all the mucous surfaces ; also by the liver, kidneys, and skin. During its excretion by the stomach, it produces a remote emetic effect in the dog. It is also excreted by the respiratory mucous membrane, and acts as a sedative expectorant. The Antidotes consist of the administration of sub- stances containing tannin, such as strong tea or coffee, or decoction of oak bark ; these form an insoluble com- pound, and prevent absorption. The vomiting should be encouraged within safe limits, and demulcents given freely to allay the gastric irritation. Medicinal Uses. — The chloride of antimony is some- times employed as a caustic application in cases of canker, foul in the feet of cattle, and foot-rot in sheep ; but in consequence of the severity of its action it must be used with great caution, and other agents are safer, while being quite as effectual. Tartar emetic is still occasionally prescribed in veterinary practice. As we are aware, it produces no effects in medicinal doses in horses and cattle ; it is difficult to understand how it can be of any therapeutical value. It is believed to improve the condition of horses by its action on the skin, and hence is employed in alterative and condition powders, in combination with other agents, but probably it is to the latter that the beneficial effects are really due. 19 Digitized by Microsoft® 290 VETERINARY THERAPEUTICS As a vermicide it is also prescribed, but we have no evidence of its action in this respect to justify its use. It may be given in doses of from 1 to 4 drachms. In the dog this drug can safely be dispensed with. It is to be avoided as an emetic, in consequence of its nauseating and depressing effects. As a sedative expectorant for similar reasons it should be avoided, as our aim in the treatment of affections requiring the use of sedative expectorants should be to sustain the strength of the patients, by encouraging the appetite and digestion, and avoiding any agent likely to irritate or nauseate. Tartar emetic is not employed externally. BISMUTHUM— BISMUTH. The chief salt of bismuth employed in veterinary practice is the subnitrate. Bismuth! Subnitras — Subniteate of Bismuth. Prepared by dissolving purified bismuth in diluted nitric acid, heating, concentrating, washing with water, and drying. Doses.— Horses, 3iv. to |i. ; dogs, grs. v. to grs. xx. Administered every two hours as required, in the form of emulsion. (1) IMMEDIATE LOCAL ACTION. Externally this salt has no effect on the unbroken skin. On inflamed or ulcerated surfaces it acts as a mild seda- tive and astringent, and a similar effect is produced on accessible mucous membranes. Internally it is insoluble in the stomach, and produces sedative and astringent effects, either by acting on the gastric nerves and local circulation, or, by acting in a Digitized by Microsoft® BISMUTH AJ^D ITS PREPARATIONS 291 mechanical manner, soothing and protecting the mucous membrane. On the intestines it also produces sedative and astrin- gent effects. (2) ACTION ON THE BLOOD, SPECIFIC ACTION, AND REMOTE LOCAL ACTION. Bismuth enters the blood in very small amount, and passes through the tissues very slowly. There are no specific effects recognised, and the drug is excreted by the kidneys, also by the intestines and respiratory mucous membrane, milk, etc. The subnitrate is partly converted into the sulphide in the intestines, causing the fseces to assume a leaden-gray colour. Medicinal Uses. — Bismuth is chiefly prescribed in canine practice in cases of gastric catarrh with obstinate vomiting, due to dyspepsia. It may be combined with the bicarbonate of sodium, dilute hydrocyanic acid, or with opium, if there be much pain present. It is also useful in cases of diarrhoea in foals, and young dogs, and may be combined in such instances with Dover's powder. As a rule, large doses are required to produce therapeutic effects. Thloform. A basic bismuth salt of dithio-salicylic acid. Digitized by Microsoft® 292 VETERINARY THERAPEUTICS CHAPTBE IV. INORGANIC MATERIA MEDIGA.— Continued. GROUP III.— THE NON-METALLIC ELEMENTS. We may subdivide the non-metallic elements into three divisions, as follows : 1. Chlorum ; ledum. ; Bromum. 2. Sulphur. 3. Oarbo. Sub-Geoup I. CHLORUM— CHLORINE GAS. Prepared by heating common salt and black oxide of manganese with sulphuric acid. Actions and Uses. — Chlorine is a disinfectant, antiseptic, and deodorizer. Its action depends partly on its power of destroying the organisms which produce putrefaction, and partly on its chemical actions. It possesses great affinity for hydrogen, and seizes upon this element in organic and inorganic substances, altering their properties, and setting free nascent oxygen, which exerts active oxida- tion. Chlorine gas dissolved in water acts as a powerful irritant to the skin, and in dilute solutions in the stomach it becomes converted into hydrochloric acid and chlorides. If the gas be inhaled, it causes local irritation of the respiratory passages. The chief use of chlorine in medicine is as a disinfectant and deodorizer, for the purpose of disinfecting sheds, buildings, etc. ; but other agents are to be preferred. It is sometimes employed as Digitized by Microsoft® IODINE AND ITS PREPARATIONS 293 an inhalation for parasitic affections of the bronchial tubes in calves and lambs, but other remedies are more effectual and less irritant. The combination of chlorine with lime has already been noticed under the heading of Calcium. lODUM— IODINE. Under this heading we will notice iodine and its com- binations with potassium and sodium. Prepared from kelp, the ashes of seaweed. Incompatibles. — Ammonia, metallic salts, mineral acids, vegetable alkaloids. Doses. — Horses, grs. x. to grs. xxx. ; dogs, gr. i. to grs. ii. Given in the form of bolus or pill. Preparations. Tinctura lodi— Tincture of Iodine — 1 in 40 ; iodine, A ; iodide of potassium, J ; spirit, 20 parts. Liquor lodi— Solution of Iodine — I in 20 ; iodine 10 ; iodide of potassium, 16 ; water, 200 parts. Unguentum lodi — 1 to 8 ; iodine 1 ; iodide of potassium , ^ ; lanolin, 4 parts ; vaseline, 4 parts. Potassii lodidum — Iodide of Potassium. Prepared by dissolving iodine in liquor potassEe, evapo- rating, mixing the residue with wood charcoal, and fusing. Doses. — Horses, 3i. to 3ii. ; cattle, 3ii. to 3iv. ; dogs, grs. ii. to grs. x. Eepeated twice daily. ACTIONS OF IODINE AND ITS PEEPAEATIONS. (1) IMMEDIATE LOCAL ACTION. Externally pure iodine acts as a stimulant to the skin, and if applied of sufficient strength is an irritant and vesicant. It stains the epidermis in light - coloured animals a deep-brown colour, and may be absorbed from Digitized by Microsoft® 294 VETERINARY THERAPEUTICS the skin into the blood. It also possesses powerful antiseptic and disinfectant properties. The iodide of potassium is devoid of local irritant effects when applied to the unbroken skin, and is not absorbed, but is readily taken up from exposed mucous membranes. Internally iodine acts as an irritant in the stomach and intestines, the iodides of potassium or sodium rarely producing this effect. It is gradually converted into the iodide or iodate of sodium ; the iodide of potassium is also decomposed in the stomach, the sodium salt and albuminate being formed. If inhaled, it produces irritating effects, giving rise to cough, dyspnoea, etc. (2) ACJTION ON THE BLOOD. Iodine is quickly absorbed into the blood from the stomach and mucous surfaces, and at first exists in the form of the iodide of sodium. The chemical or physical changes produced on the blood are not definitely ascer- tained, the results of experiments going to prove that the iodine is temporarily set free, and if administered in large amount it seems to break up some of the red corpuscles, causing hsematuria and hsemorrhagic effusion and dis- charges. Some authorities state that it increases the coagulating power of the blood. (3) SPECIFIC ACTION. Iodine passes rapidly from the blood into the tissues, being specially attracted to lymphatic glands and vessels. It quickly leaves the tissues, to be excreted by the kidneys and mucous secretions generally, and its effect on metabolism is to accelerate tissue change and promote absorption. Its action on lymphatic glands is to reduce their size. Digitized by Microsoft® IODINE AND ITS PREPARATIONS 295 Certain poisons, such as lead and mercury, which have the power of associating themselves with the albuminous structures are disengaged and removed from the system by the administration of the iodide of potassium. We have no evidence of the effects of iodine in medicinal doses on the heart, vessels, or temperature, the depressing effects noted as the results of large doses of the iodide of potassium being probably due to the action of potassium. Toxic Effects. — Iodine and iodide of potassium, given in large doses, and for a prolonged period of time, act specially on the mucous covering of the eyes, and that of the nostrils and throat, the latter effects being chiefly due to the excretion of the agent by the respiratory mucous membrane. A series of symptoms termed ' lodism ' results, con- sisting of loss of appetite, dyspepsia, an irritable catarrhal condition of the mucous membrane of the nostrils, eyes, throat, etc., these effects being rarely noticed in veterinary patients as compared with human. Professor Dick's experiments with iodine on the horse demonstrate that in some instances the only effect pro- duced was the total refusal of water by the animal. In the dog iodine in large doses causes vomition and gastro- enteritis, with hsematuria, and hsemorrhagic dis- charges from the intestines. According to Binz, it paralyzes the cerebral centres by direct action on the nervous structures, and proves fatal by this action on the respiratory centre. Antidotes. — In acute poisoning and iodism, starch should be administered, which converts any unabsorbed iodine into the insoluble starch iodide. Digitized by Microsoft® 296 VETERINARY THERAPEUTICS (4) REMOTE LOCAL ACTION. Iodine is rapidly excreted, appearing in the urine, the mucous secretions of the air-passages, the perspiration, saHva, bile, and milk. In full doses, the iodide of potassium acts as a diuretic; but this action is uncertain in different individuals, and is probably due to the alkali rather than to the iodine. The remote local action of iodine during its excretion by the respiratory mucous membrane is of therapeutical importance, as it increases and liquefies bronchial secre- tion, thus acting as an expectorant. Iodine is also excreted by the skin, causing stimulation of the epidermis, and sometimes the appearance of a papular or vesicular eruption, if administered in full doses. Medicinal Uses. — The iodide of potassium being more soluble than iodine itself, is preferred for internal admin- istration ; it is also less liable to cause gastric derange- ment. The iodide of sodium possesses similar actions. As a promoter of ahsorption iodine is prescribed in sub- acute and chronic inflammations of various kinds, such as exudations or effusions in serous cavities, and in some forms of pulmonary consolidation it probably promotes absorption by stimulating the local nutrition. In cases of pleuritic effusions, and in the secondary stages of pneumonia, it is prescribed twice daily in com- bination with tonics. As an expectorant it is useful in cases of chronic bron- chitis, and may be combined with the chloride of ammo- nium. Such a combination at first increases the amount of expectoration, but renders it less viscid and tenacious. The iodide of potassium has been extensively employed in the treatment of actinomycosis, and with evident suc- Digitized by Microsoft® IODINE AND ITS PREPARATIONS 297 cess. It is administered in doses of 90 grains in a pint of water once a day for eight or nine days. Eecently it has been demonstrated that one of the troublesome sequels of castration, termed scirrhus cord, or champignon, depends on the presence of a fungus, and a long course of the iodide of potassium has resulted in the disappearance of the morbid growth without opera- tion. The method adopted consists in the administration of 75 grains of the iodide of potassium twice daily, injec- tions of iodine being also made into the scrotal fistula. After a period of administration from one to two months the growth gradually disappears. The iodide of potassium has been employed in the treatment of chronic rheumatism, but its value in this respect is not superior to other remedies. In glandular enlargements, such as bronchocele, and in cases of abdominal tumours met with in canine prac- tice, the iodide of potassium is employed with benefit. In diabetes insipidus or polyuria, iodine is especially useful, allaying the excessive thirst and reducing the large amount of urine excreted. The manner in which it brings about these favourable results cannot be satis- factorily explained. The pure drug acts best in some cases given in doses of half a drachm, along with the sulphate of iron and gentian in bolus once a day ; but in severe cases it may be administered twice daily, care being taken to ensure a complete change of food at the same time. As a cutaneous stimulant and alterative iodine is pre- scribed in persistent cases of psoriasis, in combination with arsenic and mercury in the form of the liquor arsenii et hydrargyri iodidi, as recommended by Professor Wil- liams ('Veterinary Surgery,' p. 695). In cases of purpura hmmorrhagica in horses, especially Digitized by Microsoft® 298 VETERINARY THERAPEUTICS in those characterized b)' difficulty in deglutition, Pro- fessor Dieckerhoff and other German authorities recom- mend the intra-tracheal injection of a solution of iodine and iodide of potassium prepared with one part of iodine, five parts of iodide of potassium, and one hundred parts of water, the dose being in ordinary cases three to nine fluid drachms of this solution, slowly injected into the lumen of the trachea twice a day with an ordinary hypodermic syringe. In severe cases this quantity may be greatly increased without producing any unfavourable local effects. As an antidote in chronic cases of lead or mercury poisoning, the iodide of potassium is employed; it dis- engages these agents from the tissues, and renders them capable of being excreted from the system. In prescribing iodine it should, if possible, be given a few hours after feeding, so as to diminish the chances of a portion of it being converted into the insoluble iodide of starch, as starch forms such a large proportion of the food of herbivora. Externally iodine is applied to glandular enlargements, bursal distensions, etc., as a stimulant and absorbent. As a parasiticide it is employed in certain skin diseases, such as ringworm, and for such purposes may be com- bined in the form of ointment, with wood-tar oils, sulphur, creolin, etc. As a stimulant antiseptic and promoter of adhesion, a dilute solution of iodine is injected into cysts, etc., from which the fluid has been withdrawn. In bursal and synovial enlargements, such as capped hocks in horses, a useful application consists of equal parts of tincture of iodine, spirits of tar, and soft soap well mixed together, and applied with a brush once daily, being discontinued when the parts get tender, and re- opplied when necessary. Digitized by Microsoft® BROMINE AND ITS PREPARATIONS 299 The ointment of iodine is best prepared with one ounce of iodine, half an ounce of iodide of potassium, and eight ounces of lanoline, heating the constituents together. BROMUM— BROMINE. The preparations of bromine employed are — bromide of potassium, bromide of ammonium, bromide of sodium. Bromine, a liquid element, is obtained from sea-water and from some saline springs, by heating the natural magnesium compound with oxide of manganese and sul- phuric acid. The salt in general use is : Potassii Bromidum — Beomide of Potassium. Prepared from bromine, liquor potass^, and charcoal. Doses. — Horses and cattle, |ss. to gi. ; dogs, grs. v. to grs. XX. (1) IMMEDIATE LOCAL ACTION. Externally, pure bromine acts as a topical irritant to the skin, but the bromides possess no local irritant action unless in highly concentrated solutions, and are not absorbed from the unbroken skin. Internally, the bromides have little effect of an irritant nature on the stomach or intestines. Given in full doses they are said to diminish the sensibility of the fauces, so that reflex movements, such as swallowing, cough, etc., are not easily excited. (2) ACTION ON THE BLOOD. The bromides are rapidly absorbed, and the bromide of potassium is believed to enter the blood unchanged, and to be then converted into the sodium salt by the presence of chloride of sodium. It may be temporarily set free in the blood, but we are not aware of any special action which it exerts thereon. Digitized by Microsoft® 300 VETERINARY THERAPEUTICS (3) SPECIFIC ACTION. It seems probable that the bromides pass through the organs and tissues, as the bromide of sodium, and the speciiic action, generally speaking, is one of depression. On the nervous system they produce most important effects. They reduce the activity of the nervous centres in the brain and spinal cord, and also depress the peri- pheral (sensory) nervous filaments, the result being that after the administration of full doses, there is a loss of reflex excitability in connection with the sentient surfaces of the body. On the cerebnMii they lessen activity, and diminish cere- bral excitement by reducing the activity of the reflex portions of this region. They are thus indirect hypnotics, producing a condition of the brain favourable to sleep, and as yet we cannot determine whether this effect is due to a special action on the nerve-cells or on the cerebral blood-vessels. On the vital centres of the medulla they act as de- pressants. On the spinal centres, spinal nerves, and muscles, they cause depression, and so act as physiological antagonists to strychnine in this respect. On the heart they cause slowness of its action and weak- ness, chiefly by depressing its nervo-muscular substance, partly by depressing the cardiac centre in the medulla. On respiration they weaken and slow the respiratory movements by depressing the respiratory centre in the medulla. On the blood-vessels the direct effect is not known in a definite manner ; probably the tension in the vessels is reduced. Toxic Effects. — Given in continued large doses the bromides cause a condition termed bromism, consisting Digitized by Microsoft® BROMINE AND ITS PREPARATIONS 301 of cerebral depression, feebleness, anaemia, and the occurrence in some instances of an eruption resembling acne. (4) BEMOTE LOCAL ACTION. The bromides are quickly eliminated, chiefly by the kidneys, also by the salivary glands, skin, and all mucous surfaces. In their passage through the excretory organs they set free bromine, which exerts certain effects, when they are given continuously, such as irregular disturbance of the urinary constituents, an eruption on the skin, and sometimes conjunctivitis. Medicinal Uses. — The bromide of potassium is the salt most frequently used. In epileptic convulsions in dogs the bromide of potash often" gives favourable results as a palliative remedy. It is also useful in chorea, and in both these affections is combined with the liquor arsenicalis with benefit. The bromide of ammonium is recommended by some prac- titioners in the early stages of pneumonia in horses, when the affection is accompanied by nervous excitement. In milk fever in cows, it is recommended in combina- tion with chloral hydrate, but many practitioners prefer the latter drug administered alone. In strychnine poisoning it is inferior as an antidote compared with chloral hydrate or chloroform. In tetanus it is sometimes prescribed in combination with belladonna, but does not appear to be of any special value in the treatment of this intractable affection. Digitized by Microsoft® 302 VETERINARY THERAPEUTICS Sub-Geoup II. SULPHUR. Source. — Crude sulphur is chiefly obtained from the native sulphur, occurring as a product of volcanic action in Sicily and Italy. It is the source of all the prepara- tions, with the exception of calx sulphurata. Sulphur Sublimatum— Sublimed Sulphur — 'FLOVfEES OF SULPHUE.' Prepared from crude sulphur by subliming in large chambers. Doses. — As a laxative: Horses, §i. to §iv. ; cattle, iii. to gvi. ; sheep and pigs, 5iv. to |i. ; dogs, 3i. to ^ii. As an alterative, one-fourth of these doses is prescribed. Sulphur Prsecipitatum — Precipitated Sulphur — ' Milk of Sulphur." Prepared by boiling sublimed sulphur with slaked lime in water, precipitating the filtrate with dilute hydrochloric acid, washing and drying. Doses. — Same as those of sublimed sulphur. Sulphuris lodidum— Iodide op Sulphue. Prepared by fusing sublimed sulphur with iodine. Unguentum Sulphuris lodidL — 1 in 16| lanolin and vaseline. Calx Sulphurata— Sulphurated Limb. Prepared by heating a mixture of sulphate of calcium with wood-charcoal. Acidum Sulphurosum— Sulphueous Acid. Prepared by burning sulphur in air. Digitized by Microsoft® SULPHUR AND ITS PREPARATIONS 303 ACTIONS OF SULPHUR AND ITS PEEPARATIONS. (1) IMMEDIATE LOCAL ACTION. Externally, sulphur applied to the skin in its dry form has little or no local action. Applied in the form of ointment, it becomes partially converted by contact with the acid products of the skin into sulphuretted hydrogen and sulphides, which exert special local actions. It acts as a vascular stimularit and nervous sedative, and an alterative to the superficial layers of the skin, by stimu- lating epithelial cells, and increasing movements of cilia. Internally it undergoes no change in the stomach, and possesses no appreciable action on the organ. It is carried to the intestines, and is in part converted into sulphides by the action of the bile, producing mild purgation when given in full doses by stimulating the glandular structures, and also probably by increasing peristalsis. A considerable amount of sulphuretted hydrogen becomes generated in the intestines, and por- tion of the sulphur escapes unabsorbed in the fseces, either unchanged or as sulphides of hydrogen, or com- bined with alkalies met with in the bowel. (2) ACTION ON THE BLOOD. A certain proportion of sulphur enters the blood in the form of sulphides of hydrogen and the alkalies. We are not aware of any action which it possesses on the physical or chemical constitution of the blood. It is believed that portion becomes oxidized, appearing in the urine as a sulphate. Sulphuretted hydrogen, if inhaled by an animal, acts as a powerful blood poison, reducing the oxyhsemoglobin Digitized by Microsoft® 304 VETERINARY THERAPEUTICS of the red corpuscles, and converting the carbonates and phosphates of the white corpuscles into sulphides, sul- phites, and sulphates. (3) SPECIFIC ACTION. Sulphur in the form of hydrogen and alkaline sul- phides enters the tissues from the blood, and in exces- sive doses acts upon the central nervous system, causing depression, and finally paralysis of the centres of respira- tion and circulation, besides giving rise to inflammation of the stomach and intestines, as proved by the experi- ments of Moiroud and Hertwig. In medicinal doses we believe that sulphur possesses the effect of modifying nutrition, and thus acting as an alterative. (4) EEMOTB LOCAL ACTION. Sulphur is excreted by the kidneys, hj the skin, the lungs and the bronchii, and by the intestines. By the Mdneys it is excreted in the form of sulphates, and if in excess as sulphides also ; the constituents of the urine are not altered, with the exception of the in- crease of the sulphur compounds. By the skin it is excreted in the form of sulphides and sulphuretted hydrogen, giving a characteristic odour to the perspiration, increasing slightly the amount of the latter, and acting as a mild cutaneous stimulant and diaphoretic. By the lungs and bronchii it is excreted in the form of sulphides, and is believed to act as a mild expectorant. By the intestines it acts as a purgative alterative. Medicinal Uses. — Internally. — As an alterative sulphur is extensively prescribed in affections of the skin, such as acne, eczema, etc. ; also in dry, scurfy conditions of the skin, and general want of condition. It is given either Digitized by Microsoft® SULPHUR AND ITS PREPARATIONS 305 in the sublimed or precipitated forms, or in the form of the sulphide of calcium. As a laxative it is sometimes employed in cattle prac- tice, and frequently in canine practice ; its action as a laxative as well as an alterative rendering it an agent of great value in the latter, and being almost devoid of taste it is readily taken in the food. As an expectorant it is seldom prescribed, and its action in this respect appears to be slight. Externally . — As a parasiticide it is extensively em- ployed in the treatment of mange in all species of animals. It is used in various combinations, in the form of lini- ments, ointments, etc. Experiments and practical ex- perience prove that the efficacy of sulphur for such purposes is greatly increased by combining it with an alkali, such as the carbonate of potassium. It is believed that the parasites on which mange depends are destroyed by the formation of sulphuretted hydrogen and other toxic sulphides, the combination of the sulphur with the alkali increasing the production of these compounds, besides tending to soften and remove the crusts and scales on the skin. Two parts of sublimed sulphur and one part of carbonate of potassium, dissolved by the aid of gentle heat, in eight parts of lard or oil, make a useful application for such cases, the addition to this of one part of the oil of tar rendering it more ef6.cacious. Before being applied, the parts should be thoroughly washed with soft soap and warm water, so as to enable the application to act directly on the parasites. It should be allowed to remain on for two days, and then be washed off, and reapplied if necessary. As a dip for sheep, sulphur is highly recommended in the form of the sulphide of calcium, prepared as follows : Boil one part of quicklime with two of sublimed sulphur 20 Digitized by Microsoft® 306 VETERINARY THERAPEUTICS in ten parts of water until the sulphur and lime com- bine, let the solution stand, and pour off the clear portion. A sufBcient amount can be prepared in similar propor- tions to the above. As a cutaneous stimulant and alterative, sulphur in various forms of combinations is employed as an applica- tion to affections of the skin, such as chronic eczema, psoriasis, etc., stimulating epithelial cells, hastening desquamation, and thus promoting a healthier action in the parts. The ointment composed of sublimed sulphur and carbonate of potash, already mentioned, is very use- ful for such purposes. The iodide of sulphur, in the form of ointment (1 to 8) acts very beneficially in some forms of chronic scaly skin affections, and also in cases of ringworm. Sulphurous acid is employed as a disinfectant for stables and premises, the gas being evolved by burning sulphur mixed with one-fortieth part of finely-divided charcoal. It is sometimes used as an inhalation for destroying bronchial filarite in calves and lambs. Sub-Geoup III. CARBO— CARBON. Two forms of carbon are recognised, viz. : 1. Carbo Animalis. 2. Carbo Ligni. (1) Carbo Animalis — Animal Chaecoal. PrejMred by exposing bones to a red heat, excluding air, and powdering the residue. The purified animal charcoal is prepared by digesting the agent in diluted hydrochloric acid, and thus removing the salts therefrom. Digitized by Microsoft® CARBON AND ITS PREPARATIONS 307 (2) Carbo Ligni — Wood Chaecoal. Prepared from wood charred by exposure to a red heat, and excluding air. General Actions. — Externally charcoal acts as a clesic- cant, disinfectant, and deodorant. It possesses the pro- perty of absorbing and condensing many gaseous bodies and vapours, it absorbs but little hydrogen, although it will take up a considerable amount of oxygen, and large quantities of sulphuretted hydrogen and ammonia. Its action on noxious gases is believed to depend on the oxygen which it retains decomposing and deodorizing them. Some authorities state that it has the power of absorbing and condensing the noxious gases in its pores. Internally, charcoal given in sufficient amount has the power of checking fermentative changes while passing through the alimentary canal, and by virtue of this action it will prevent the occurrence of flatulence. It possesses the power of attracting alkaloids from their solutions in the stomach, and rendering them inert ; hence animal charcoal has been recommended by Dr. Garrod as an antidote in cases of poisoning by morphia, aconite, strychnia, etc. Charcoal is removed from the system entirely by the intestines, and not being absorbed, it does not exert any specific action on the body. Medicinal Uses. — As an agent to check the formation of gases due to fermentative changes in the alimentary canal, charcoal is sometimes prescribed in cases of flatulence in doses of §ss. to §ii. for horses and cattle, and grs. xx. to 3i. for dogs. Externally. — It is occasionally employed as a deodorant and disinfectant to unhealthy ulcers or foul wounds, being applied directly in the dry form ; but as it possesses no action as an antiseptic, other agents are to be preferred. Digitized by Microsoft® 308 VETERINARY THERAPEUTICS CHAPTEE V. INORGANIC MATERIA MEDIOA.— Continued. GEOUP IV.— ACIDS. Foe convenience of description, we may arrange the official acids in common use under two headings : 1. INORGANIC ACIDS. Sulphuric ; Nitric ; HydrocMoric ; Nitro-hydrochloric ; Boric ; Chromic. 2. ORGANIC ACIDS. Acetic ; Citric ; Tartaric ; Hydrocyanic ; Carbolic ; Gallic and Tannic ; Salicylic. Of the organic acids, only the first three will be noticed in this chapter, as the actions and uses of the remainder are but slightly connected with their properties as acids. We shall first briefly notice the general actions of acids before proceeding to a consideration of the actions and uses of each acid separately. (1) IMMEDIATE LOCAL ACTION. Externally. — The strong acids — such as sulphuric, hydrochloric, and nitric — are caustic and irritant, and in concentrated form are powerful corrosives. They pro- duce these effects by their affinity for the bases and water of the tissues, and in a lesser degree for the organic substances therein. Properly diluted, they act as astringents when applied to the skin, mucous mem- Digitized by Microsoft® GENERAL ACTIONS OF ACIDS 309 branes, etc., causing a direct condensation of the tissues, and thus checking haemorrhage from small vessels and capillaries. Internally. — In the mouth they act as sialagogues, being powerful stimulants of salivary secretion, this action depending on an impression reflected through the cerebro-spinal nerves supplying the salivary glands. They are in part neutralized by the alkaline secretion from the salivary glands, the resulting salts exerting some astringent effects. In the stomach — acids act directly upon the contents of this organ ; the free acids quickly unite with bases in the digestive tract, and form neutral salts. Hydrochloric acid increases the acidity of the gastric juice when given after feeding, thus acting as a digestive adjuvant. In the duodenum acids increase the acidity of the chyme, stimulate the intestinal glands and muscular coat of the intestine, and also stimulate the liver and pancreas. The dilute sulphuric acid acts as an intestinal astringent. (2) ACTION ON THE BLOOD. Acids on entering the blood combine with part of the alkali of the liq. sanguinis, and thus render the blood less alkaline; but even when given in toxic doses they do not produce an acid reaction in this fluid. We are not aware of any further effects which they are capable of producing on the blood. The vegetable acids, when administered as salts of the alkalies, have a deoxidizing effect on the blood. (3) SPECIFIC ACTIONS. On the different tissues and organs of the body each of the acids possesses a specific action of its own. There are, however, some important actions which Digitized by Microsoft® 310 VETERINARY THERAPEUTICS acids exert on the salivary and digestive secretions, and of these vye shall now give a brief notice : On the salivary secretion they act as powerful siala- gogues ; the impression from the acid is conducted to the nerve centres, and is then reflected through the cerebro-spinal nerves supplying the salivary glands. On digestion — dilute acids taken into the stomach check or lessen the secretion of gastric juice ; they also cause an increased flow of bile, probably by rendering the contents of the duodenum of an acid reaction, and increase the activity of the intestinal glands and muscles. All these effects must be attributed to a law ■which is proved both by experiment and also by the employment of acids in therapeutics — viz., that acids check acid blit increase alkaline secretions, while dilute alkalies stimu- late acid secretions. These facts are explained in an admirable manner by Dr. Einger in his work on ' Therapeutics,' and they are most important in the treatment of the disorders of the digestive system, as indicating whether acids or alkalies should be prescribed. Dr. Einger supports these views by illustrations of the therapeutic employment of acids or alkalies, as follows : 1. Acids allay thirst by promoting the secretion of the alkaline saliva. 2. Acids given shortly before feeding generally check acidity. 3. Alkalies given shortly before feeding increase the secretion of the acid gastric juice, and so promote digestion. Acids check fermentation, and the formation of gases and irritating organic acids in the intestines, and thus act antiseptically in this respect. Digitized by Microsoft® SULPHURIC ACID 311 In toxic doses, and in concentrated form, acids are corrosive irritant poisons, nitric and sulphuric acids possessing these actions in a most marked degree. The suitable antidotes are alkaline bicarbonates, calcium and magnesium carbonates, given with demulcents and diluents — such as oils, milk, linseed-tea — the addition of an anodyne— such as opium — being often required. (4) EEMOTE LOCAL ACTION. Acids having entered into combination as neutral salts, or having been decomposed in the blood, are re- moved from the system, and during this process they exert very little local action. They are chiefly excreted by the kidneys, stimulating these organs by increasing the total amount of salts excreted ; but they do not to any extent increase the free acidity of the urine. Acetic, citric, and tartaric acids never reach the tissues unless given in large doses ; they are decomposed in the blood, and excreted as carbonates. Given in excess, they escape unchanged by the kidneys. INORGANIC ACIDS. (1) Acidum Sulphuricum — Sulphueic Acid, Oil of VlTEIOL. Prepared by the combustion of sulphur, and the oxidation and hydration of the resulting sulphurous acid by means of nitrous and aqueous vapours. Con- tains 98 per cent, of real acid. Preparations. (a) Acidum Sulphuricum Dilutum. — Dilute sulphuric acid. — 1 to about 11 of distilled water. Ptoses. — Of the dilute acid : Horses, 3i. to 5ii. ; cattle, 3ii. to 3iv. ; dogs, TTl_v. to TT|^xx. — administered, freely diluted, twice daily, and combined with aromatics and bitters. Digitized by Microsoft® 312 VETERINARY THERAPEUTICS (b) Acidum Sulphuricum Aromaticum. — Prepared by- mixing sulphuric acid, 1| ; spirit, 18 ; spirit of cin- namon, 1 ; strong tincture of ginger, 1. Contains 12-5 per cent, of real acid. Doses. — Similar to those of the dilute acid. Actions — Externally. — Strong sulphuric acid absorbs water with avidity from the tissues, and has also an af&nity for their bases, and to a less degree for the organic substances themselves. For these reasons, when applied locally, it destroys the tissues to a considerable extent, producing a hroion or hlack eschar and a powerful corrosive action. Internally. — The dilute and aromatic preparations only are employed internally. These act as tonics and astringents, the tonic action probably depending on a stimulating effect upon the gastric and biliary functions, the astringent action probably on an astringent effect on the bloodvessels. It must be remarked, however, that the acid is soon neutralized in the upper part of the small intestines, being converted into a sulphate, thus losing its astrin- gency. It is excreted chiefly by the kidneys, increasing to a slight extent the amount of sulphates in the urine ; it is probable that part escapes by the bowels as sulphates of sodium and magnesium, and a certain portion possibly by the skin. Toxic Effects. — Sulphuric acid acts as a corrosive irritant poison, producing in concentrated form patches of erosion of a brown or black colour on the mouth, fauces, oesophagus, and mucous membrane of the stomach, with perforation of the latter in some instances. The throat becomes acutely inflamed, extensive swelling resulting, with rapid death from suffocation. In dogs it causes immediately retching and emesis, Digitized by Microsoft® NITRIC ACID 313 the vomited matters being dark-coloured and blood- stained. The antidotes are alkaline bicarbonates, chalk, or carbonate of magnesia, given in small quantities frequently repeated, with a liberal administration of demulcents. Medicinal Uses — Internally. — As a tonic and astringent, the medicinal preparations are prescribed in chronic diarrhcea and dysentery, generally combined with a preparation of opium, carminatives, etc., and administsred in starch gruel. It is recommended by some practitioners in the treatment of purpura haemorrhagica in horses, being prescribed with the sulphate of iron. It is an efficient antidote in cases of poisoning by lead and by alkalies. In pharmacy it is employed as a solvent in dispensing sulphate of quinine in the form of mixtures. Externally . — Sulphuric acid is occasionally employed as a caustic to destroy some forms of malignant growths, being mixed with suitable substances for such purposes. It is recommended as an application to contract and remove umbilical hernise, being applied either pure or mixed with linseed-oil. (2) Acidum Nitricum— Niteic Acid, Aquapoetis. Prepared from nitrate of potassium by distillation with sulphuric acid and water. Contains 70 per cent, of real nitric acid. Preparation. Acidum Nitricum Dilutum. — 1 to 4 of distilled water. Doses. — Of the diluted acid : horses or cattle, Jss. to 5ii. ; dogs, ni_v. to TT1_x. properly diluted. Actions — Externally. — Nitric acid, not possessing so strong an affinity for water, and not readily redissolving Digitized by Microsoft® 314 VETERINARY THERAPEUTICS precipitated albumin, is not so penetrating as sul- phuric acid, and hence, when locally applied, destroys the tissues less extensively. It stains the skin a characteristic yelloiv colour, due to the formation of picric acid. This colour is deepened by alkalies, and removed only by desquamation of the cuticle. The action of nitric acid on the skin and tissues is comparatively speaking slow, but is usually very deep- seated, especially if close to the flexure of a joint, an extensive slough often resulting. Internally the dilute nitric acid acts as a cholagogue, probably in part by its action on the mucous membrane of the duodenum, causing an increased flow of bile, by consequent contraction of the gall-bladder and bile-ducts; also, probably by the contents of the duodenum being rendered acid, the secretion of the alkaline bile is stimulated. Nitric acid possesses similar actions to other acids on the alimentary canal and on digestion. It is believed to be partly decomposed in the system into ammonia, and during its excretion by the kidneys to diminish slightly the acidity of the urine. Toxic Effects. — Nitric acid is a corrosive irritant poison, especially when in concentrated form. It causes yellow or brown stains in the mouth, pharynx, and oesophagus ; but in the mucous membrane of the stomach these are usually rendered obscure by the acute inflam- matory changes, often accompanied by extravasation of blood. The antidotes are similar to those employed for the other mineral acids. Medicinal Uses. — As a hepatic stimulant dilute nitric acid is prescribed after feeding, in cases of torpidity of the liver accompanied with intestinal dyspepsia. It is Digitized by Microsoft® HYDROCHLORIC ACID 315 also useful in long-standing affections of the liverj such as chronic congestion and cirrhosis. In cases of diarrhcsa, especially in young animals, where the motions are greenish in colour, curdled, and mixed with mucus, small doses of dilute nitric acid are often of great benefit. Nitric acid should be given largely diluted with water, and is usually combined with aromatic bitters. Externally nitric acid is employed for the removal of warts, fungous growths, etc. It should be carefully applied with a glass rod, precautions being taken to prevent the surrounding tissues being injured, and also to guard against its action extending too deeply. (3) Acidum Hydrochloricum--HYDEocHLOEic Acid, Muriatic Acid, Spieit op Salt. Prepared by the action of sulphuric acid upon chloride of sodium and solution of the fumes in water. Contains 32 per cent, by weight of the gas dissolved in water. Acidum Hydrochloricum Dilutum — Dilute hydrochloric acid — 1 to 2^ distilled water. Doses. — Of the dilute acid : horses, Jss. to 3ii- ; cattle, Jii. to 5iv. ; sheep, ni_xv. to lT(_xx. ; dogs, ni_v. to lTl_x. properly diluted. Actions — Externally. — Hydrochloric acid is an active caustic, causing the formation of a white film on the tissues when applied in concentrated form. It is less corrosive in its action than nitric or sulphuric acid. Internally. — In the mouth it is a stimulant and sialagogue, increasing the flow of saliva, and thus indirectly, as well as reflexly, of the gastric juice. In the stomach it increases the acidity of the gastric juice, and acts as a digestive adjuvant. It enters the tissues in the form of chlorides, possessing no appreciable specific Digitized by Microsoft® 316 VETERINARY THERAPEUTICS action thereon. It is excreted chiefly by the kidneys, but does not increase to any extent the free acidity of the urine. Toxic Effects. -^These resemble those of the other mineral acids, but, independent of its irritant or corrosive effects, it is believed to destroy life by causing a fatal diminution of the alkali in the blood, resulting in paralysis of the respiratory centre. Medicinal Uses. — As a sialagogue, hydrochloric acid, largely diluted with water, is sometimes prescribed in cases of fever accompanied with excessive thirst and a parched condition of the mouth. It relieves the throat by stimulating the secretion of saUva, and, besides, increases the appetite, and favours digestion by stimulat- ing indirectly, as well as reflexly, the gastric secretion. As a digestive adjuvant it is extensively employed, in consequence of its special action in digesting and render- ing soluble the albuminous constituents of the food. It is important, however, to remember the influence of the time of administration as regards prescribing the acid before or after feeding. Thus, in cases where the secretion of the gastric juice is scanty, and not suflicient to perform the function of digestion in a normal manner, the acid should be administered after feeding. "When the gastric secretion is completed, the acid then makes up for the deficiency of that which should be secreted naturally. On the other hand, when there is an excess of acid secreted in the stomach, giving rise to a condition of undue acidity of the gastric contents, the administration of dilute hydrochloric acid before feeding will overcome this con- dition. The rationale of this depends on the rule that acids check the production of acid secretions from the glands, Digitized by Microsoft® HYDROCHLORIC ACID 317 while they increase the flow of allcaline secretions, the very reverse being the case with alkalies. Acidity of the stomach, however, does not always depend on an excessive secretion of gastric juice ; it is often due to an excessive or irregular fermentation in the contents of the organ, leading to the formation of large amounts of various acids, such as acetic, butyric, and lactic ; and here also the administration of dilute hydro- chloric acid checks this irregular fermentation. It is best combined with vegetable tonics and bitters for such purposes, care being taken not to continue the adminis- tration for too long a period, which would tend to induce the opposite condition to that for which it was employed in the first instance. As alkalies administered before feeding increase the secretion of gastric juice, it becomes a question for the practitioner as to whether he shall prescribe an acid or an alkali in cases of dyspepsia depending on a scanty secretion of gastric juice. Practical experience teaches that no hard and fast rule can be laid down. In some cases alkalies administered shortly before feeding give better results than acids administered after feeding; while in others the reverse holds good. It is evident that in cases of acidity of the stomach depending on excessive secretion, acids given after feeding would increase the abnormal condition and aggravate it. In cases of renal concretions, also in cases charac- terized by the appearance of an excessive sediment in the urine, small doses of the dilute hydrochloric acid are recommended, as this agent possesses the power of dissolving the earthy carbonates, rendering them soluble, and capable of being removed in the urine. Externally .—ItydLicochlonc. acid is occasionally em- Digitized by Microsoft® 318 VETERINARY THERAPEUTICS ployed as a caustic iu the removal of warty growths, etc., and also in combination with other agents as an applica- tion io foot-rot in sheep. In superficial necrosis of bone it is useful, properly diluted, removing the diseased portion and leaving a healthy surface to heal. (4) Acidum Nitro-hydrochloricum — Niteo - Hydeo - CHLOEIC AOID, NiTEO-MuEIATIC AciD. Prepared by mixing one part of nitric acid and three of hydrochloric acid. Acidum Nitro-Hydrochloricum Dilutum — Dilute Nitro- Hydrochloric Acid. Prepared by mixing 3 ounces of nitric acid and 4 ounces of hydrochloric acid with 25 ounces of distilled water. It contains free chlorine, hydrochloric, nitric, and nitrous acids, with other compounds, dissolved in water, and should be prepared fourteen days before using. Doses. — The same as those of dilute nitric acid, with similar precautions as to dilution and the avoidance of too prolonged use. Actions — Externally. — -The strong acid is corrosive and irritant. It is believed to produce a cholagogue effect locally as well as specifically, when applied as a compress wrung out of a solution of the acid over the hepatic region in the case of liver affections in dogs. Internally. — It acts as a direct cholagogue, as demon- strated by the experiments by Dr. Eutherford ; this action is also proved by the results of clinical experience. It resembles the other acids in its action on the stomach and intestines. Medicinal Uses. — As a cholagogue it is prescribed in torpidity of the liver, in catarrhal jaundice, and in the early stages of cirrhosis, also in intestinal dyspepsia, It Digitized by Microsoft® BORIC ACID 319 is contra-indicated in cases of jaundice depending on obstruction in the bile-duct, also in severe organic affec- tions of the liver, and in acute hepatitis. In that affection of horses termed oxaluria, charac- terized by debility, loss of flesh, stiffness in the loins, a dry scurfy condition of the skin, the frequent passage of pale-coloured urine, acid or neutral in reaction, and con- taining oxalate of lime, the uitro-hydrochloric acid, in combination with tincture of nux vomica and gentian, gives very beneficial results. This affection depending on impaired digestion, due to dietetic errors, it is necessary that dietetic and hygienic precautions be adopted in addition to medicinal treatment. The acid is not employed externally, except occasionally as a local application in dilute solution in some hepatic affections, as already mentioned. (5) Acid Boricum — Boeic Acid, Boeacic Acid. Prepared by the action of sulphuric acid on borax, or by the purification of native boric acid. Doses. — Horses and cattle, 3ii. to 5iv. ; dogs, grs. v. to grs. XX. Preparatio7is . (1) Unguentum Acidi Borici — Boric ointment — 1 to 6 of hard and soft paraffin. (2) Boroglyceride (not official) is prepared by heating 92 parts of glycerine -with. 62 parts of boric acid. Borax — Biboeatb of Sodium. Prepared by boiling together boric acid and carbonate of soda. It is also found native. Prep)arations. (1) Glycerinum Boracis — Borax,!; glycerine, 4; water, 2. (2) Mel Boracis — Borax, 2 ; glycerine, 1 ; clarified honey, 16. Digitized by Microsoft® 320 VETERINARY THERAPEUTICS Actions — Externally. — Boric acid is antiseptic and disinfectant. In solution of 1 in 800 it is capable of destroying low organisms, but is not, however, destruc- tive to all growths of this nature. It has little or no irritating effect on the tissues, in this respect differing from carbolic acid and other disinfectants. Internally it checks fermentation in the alimentary canal ; it is excreted in the urine, exerting an antiseptic effect on the urino-genital canal. In toxic doses it acts as a gastro-intestinal irritant. Borax possesses similar actions to those of boric acid. Medicinal Uses — Boric acid and borax are occasionally employed internally in cases of fermentative diarrhoea in foals, calves, and dogs, also in some cases of cystic' catarrh, by reason of its remote local antiseptic action on this region. In aphthous conditions of the mouth, in ulcerations of the mouth, tongue, and fauces, and in glossitis, it is em- ployed in the form of a mouth-wash, in combination with the chlorate of potash, honey, or glycerine. As an antiseptic dressing for wounds, boric acid is largely employed in the form of lotion, in the proportion of a 5 per cent, solution. It is also very useful in the form of dry powder, combined with a certain proportion of creolin. In different forms it is in frequent use as an application to burns and ulcerated surfaces. In erythema, in irritable conditions of the skin, and in eczema in dogs, the employment of boric acid in the form of ointment, as follows, often gives most satisfactory results : boric acid, 5 parts ; lanoline, 5 parts ; vaseline, 1 part. In canker of the ear in dogs boric acid is successfully employed, either in the form of lotion or of the ointment just mentioned, combined with oxide of zinc. For a Digitized by Microsoft® ORGANIC ACIDS 321 similar purpose the dusting powder, composed of boric acid and creolin, is also very useful. In catarrhal and purulent conjunctivitis a lotion con- sisting of from three to six grains of boric acid to the ounce of aqua laurocerasi, applied three or four times daily, gives excellent results, lessening irritability and reducing the discharge. In severe cases this treatment may be alternated with atropine lotions. (6) Acidum Chromicum — Chbomic Acid, Cheomio Anhydeide (not a true acid). Prepared from potassium bichromate. Actions. — Chromic acid is a penetrating caustic and eseharotic, also a disinfectant and deodorant. It coagulates albumin, and is a powerful oxidizing body, destroying the organisms and products of decomposition. It also decomposes ammonia and sulphuretted hydrogen. Medicinal Uses. — It is not prescribed internally. As an eseharotic and caustic it is recommended by Pro- fessor Williams as an application to that intractable affection of the foot of the horse termed canker. For this purpose it should be sparingly applied, as in conse- quence of its great affinity for water a blaze of fire results from the intensity of the combination. ORGANIC ACIDS. Acidum Aceticum — Acetic acid contains 33 per cent, of real acetic acid by weight in water. Prepared from wood by destructive distillation and purification. Acidum Aceticum Dilutum — 1 to 7 of distilled water. Acidum Aceticum Grlaciale — Glacial Acetic Acid — con- tains 99 per cent, of real acetic acid with water. Prepared by distillation from acetate of sodium and sulphuric acid. 21 Digitized by Microsoft® 322 VETERINARY THERAPEUTICS Acetum- -Vinegar — contains 5-il per cent, of acetic acid. Prepared from a mixture of malt and unmalted grain by the acetous fermentation. Actions. — Strong acetic acid is corrosive and irritant when applied to the skin ; the medicinal acid acts as a vesicant and stimulant when applied in sufficient amount. Properly diluted, or in the form of vinegar, it is stimu- lant, astringent, and refrigerant. When administered internally, it reaches the blood and becomes decomposed, passing out of the system as carbonates, but when given in excess it escapes unchanged by the kidneys. Medicinal Uses. — Acetic acid is not employed internally. It may be used as an antidote in cases of poisoning by alkalies and alkaline carbonates, and also when properly diluted, as an application to surfaces irritated by strong alkalies. The strong acid is frequently employed as a caustic in the destruction of warts. In the form of vinegar it is used as a cooling and astringent application to strains and contusions, either alone or combined with other agents. In pharmacy it is employed as a solvent for various drugs, as it is capable of dissolving their active principles, such combinations being termed aceta. Example — Acetum cantharidis. Acidum Citricum — Citric Acid. Acidum Tartaricum — Taetaeic Acid. Both these acids are devoid of irritant and poisonous properties, and are occasionally prescribed as cooling antipyretics ; they relieve thirst, and, like other organic bodies, are excreted as carbonates, probably stimulating the kidneys and skin indirectly by increasing the total amount of salts excreted. Digitized by Microsoft® WA TER 323 GROUP v.— WATEE— AQUA. Aqua Destillata — Pure Water obtained by Distillation. (1) IMMEDIATE LOCAL ACTION. Externally water acts chiefly as a means of applying cold or heat to the surface of the body, depending on the temperature which is employed, whether cold, temperate, tepid, warm, hot, etc., the effects of which have already been noticed in Part II., p. 203. Internally it relieves thirst, improves digestion and intestinal action when allowed at proper times. In the dog, hot water acts as a gastric sedative, and warm water as an emetic. (2) ACTION ON THE BLOOD. Water readily passes into the blood, but this process varies according to circumstances. In cases where a large amount of fluid is removed from the system, water is quickly absorbed, while if there is a sufficient amount of this agent in the blood already, the absorption of a further quantity from the alimentary canal is diminished. (3) REMOTE LOCAL ACTION. Excess of water is eliminated by the kidneys, skin, lungs, bowels, but chiefly by the kidneys, acting as a diuretic. Administered warm, and combined with ex- ternal heat, it acts as a diaphoretic. (4) USES. As a diluent and febrifuge cold water is liberally allowed in cases of febrile affections, the vessel containing it being left within reach of the animal, so that it can be partaken of at pleasure, and saline febrifuges dissolved in it give Digitized by Microsoft® 324 VETEBINABY THERAPEUTICS beneficial results. Cold water is contra-indicated di- rectly after feeding, also when animals are in a heated condition after exertion. After the administration of a cathartic dose, and until the physic has ceased to operate, cold water should be studiously avoided, as it is likely to induce superpurgation, or spasm of the intestines. Externally water is extensively employed, either hot, in the form of fomentations, or cold as a refrigerant. The employment of hot or cold applications is often a matter of choice with the practitioner. We must, how- ever, draw attention to the beneficial effects of continuous irrigation in severe cases of broken knees, open joints, etc. (see p. 204). Digitized by Microsoft® ALCOHOL 325 CHAPTEE VI. GROUP VL— THE CARBON COMPOUNDS. ALCOHOL. The following forms of alcohol are those of chief import- ance in therapeutics : (1) Spiritus Rectificatus — Ebctified Spirit. Alcohol with 16 per cent, of water. Prepared by distillation of fermented saccharine fluids. (2) Spiritus Tenuior — Peoop Spieit. Alcohol with 51 per cent, by weight of water. Prepared by mixing 5 parts of rectified spirit with 3 parts of water. (3) Spiritus Vini Callici— Beandy. Contains from 48 to 56 per cent, by volume of abso- lute alcohol. Prepared by distillation from French wines. (4) Spiritus Frumenti — Whisky. Contains about 44 to 50 per cent, of absolute alcohol. Prepared by distilling a thoroughly fermented solution of malt. (5) Vinum Xericum — Shbeey. Contains about 17 per cent, of alcohol. Prepared from the fermented juice of the grape. Digitized by Microsoft® 326 VETERINARY THERAPEUTICS (6) Gin— Hollands— Geneva. Contain from 40 to 50 per cent, of alcohol, and are prepared from fermented malt, with a small quantity of juniper berries. (7) Port and Madeira Wines. €!ontain from 14 to 18 per cent, of alcohol. (8) Ales and Porter. Contain from 4 to 8 per cent, of alcohol, and are pre- pared from malt, with hops and yeast. (9) Methylated Spirit. A mixture of 90 parts of rectified spirit with 10 parts of wood-spirit or impure methylic alcohol. It is chiefly used for pharmaceutical purposes. The methylated spirit for retail use has the addition of 3 pints of petroleum oil to 100 gallons of the above. THE ACTIONS OP ALCOHOL AND ITS PEEPAEATIONS. (1) IMMEDIATE LOCAL ACTION. Externally alcohol is a powerful refrigerant ; it withdraws heat from the surface by its evaporation, lessens the local cutaneous circulation by vascular con- striction, and produces a sensation of cold. If the vapour be confined and allowed to act on the tissues beneath, or if the agent be rubbed into the part, it acts as a stimulant and rubefacient by penetrating the epithelium and irri- tating the nerves and vessels of the cutaneous structures, the results being redness, heat, and pain, followed by local anaesthesia. It is antiseptic and disinfectant when Digitized by Microsoft® ALCOHOL 327 employed as a constituent of lotions for wounds and ulcers, and possesses the power of hardening the epi- dermis. It can be absorbed by the unbroken skin. Internally it has the property of coagulating albu- min, and constringing to a small extent the mucous membranes of the mouth if it be retained in contact with them. It stimulates the flow of saliva, and gives an increased relish for food. *' In the stomach alcohol, in a moderate dose, produces the following important effects : (a) It mixes with the contents of the stomach, and is partly decomposed into aldehyde and acetic acid. It precipitates a portion of the pepsin, as well as of the peptones and proteids ; thus, to a certain extent, it retards digestion. (6) It stimulates the gastric mucous membrane, dilat- ing the vessels, and increasing the blood-supply and the flow of gastric juice ; the appetite is sharpened, and the movements of the stomach become more energetic, the total effect of a moderate dose thus being to favour gastric digestion. (c) Alcohol produces important effects of a reflex nature from its action on the gastric walls. The heart is stimulated, and the general blood-pressure raised ; the active organs are filled with blood, and their activity thus increased, the agent producing the characteristic effects of a diffusible stimulant. (2) ACTION ON THE BLOOD. Owing to its high diffusion-power alcohol passes readily into the blood. It enters either unchanged or as an aldehyde, and is distributed to the tissues and organs. The precise action of alcohol on the corpuscles of the blood is not yet accurately determined ; it is supposed to Digitized by Microsoft® 328 VETERINARY THERAPEUTICS have the effect of binding the oxygen more firmly to the hamogloiin, with the result that oxygenation of the tissues occurs less freely and less extensively. (3) SPECIFIC ACTION. On the tissues and organs alcohol exerts several important actions, which we shall refer to under the following headings : (a) Alcohol as a Food. — Given in moderate quantity alcohol becomes oxidized in the tissues, carbonic acid and water being produced, so that it resembles other carbo-hydrates, being a source of energy, and thus acting as a food. Given in large amounts, it may pass out of the system by the lungs, kidneys, etc., before oxidation has had time to take place. Alcohol does not become an integral part of the living cells ; it remains in the plasma surrounding the cells, where, being oxidized, it supplies an amount of energy to the active elements ; thus, it can temporarily sustain life when, from some cause, a sufficient amount of food cannot be taken or assimilated. (b) Alcohol as a Nutritive Depressant. — It has been demonstrated by experiments that alcohol interferes with the 7netaholism or oxidation of the tissue proteids or formed protoplasm of the cells, or, in other words, it spares the wear and tear of the tissues. In experiments moderate doses of alcohol were given to animals, and the following deductions were arrived at : Firstly, less oxygen was absorbed ; this is supposed to depend on the power of interference which alcohol possesses over the oxygenating function of the red cor- puscles. Secondly, the temperature fell, and the albu- minous tissues, while not wasting, tended to degenerate into fat, so that the whole system inclined to grow gross Digitized by Microsoft® ALCOHOL 329 and fat. Thirdly, there was a diminution in the amount of urea, uric acid, carbonic acid, and salts excreted. These effects are believed to depend on the readiness with which alcohol, when it reaches the tissues, seizes on the oxygen which is present, and thus deprives the fixed elements of their proper share, with the result that their decomposition is arrested at the middle stage of fat formation. We thus observe that alcohol has the property of saving tissue waste. (c) On the heart and circulation alcohol acts as a stimulant. It increases the force and frequency of the heart's action, and causes dilatation of the peripheral bloodvessels, the total effect being increased circulatory activity. This effect depends both on reflex stimulation from the mucous membrane of the stomach, and on direct stimulation of the nervo - muscular structures of the heart itself ; also of the cardiac centre, and of the nervo-muscular tissim of the middle coat of the vessels. Administered in large doses, this stimulant effect of alcohol on the circulation is followed by depression, both reflex and direct. According to Dr. Einger (' Handbook of Therapeutics '), alcohol in health dilates the arterioles, and makes the pulse larger and softer ; while in disease, or when from other causes the arterioles are relaxed, it contracts them, rendering the pulse smaller, slower, less frequent, and more resistant ; thus, it strengthens the pulse and re- duces its frequency, and must be considered one of the most powerful cardiac tonics. (d) On the nervous system the primary effect of alcohol in moderate amount is that of stimulation. The nSrve - centres are stimulated, commencing from the highest to the lowest ; but in animals, in conse- quence of the inferior development of the cerebrum. Digitized by Microsoft® 330 VETERINARY THERAPEUTICS alcohol in full doses has the effect of disturbing motor functions rather than intellectual. In large amounts, the primary stimulant effects quickly give way to depression of all the nerve-centres, finally terminating in complete arrest of their function. The muscles become first ataxic and then paralyzed, so that the standing posture becomes difficult or impossible ; the respiratory and circulatory centres may be depressed to such an extent as to cause stertorous breathing, failure of the circulation, and death. The effects of alcohol on the nerve-centres are partly due to — (a) Dilatation of the bloodvessels of the brain and cord ; (b) partly to a direct action of the drug upon the nerve-cells. (e) On Respiration. — Alcohol acts partly through its influence on the respiratory centre, and partly through the respiratory muscles and the circulation. The respira- tions are first accelerated, then slowed and weakened, death occurring by asphyxia after excessive doses. (/) On the Body Temperature. — Alcohol, as the result of the following actions, has the effect of lowering tem- perature when administered in full doses : (1) By increasing the circulation through the dilated peripheral vessels. (2) By diminishing metabolism. (3) By increasing perspiration. Very large doses lower the temperature to a great extent by causing general vital depression, vaso-motor paresis, and rapid refrigeration, especially in a low state of the external temperature. Moderate doses of alcohol in a temperate atmosphere cause a sensation of warmth by diverting the blood to the skin. Toxic Effects. — In excessive doses alcohol acts as a narcotic poison, causing paralysis of the vital nerve- centres. The higher centres are first affected, causing a Digitized by Microsoft® ALCOHOL 331 brief stage of excitement, soon terminating in profound narcosis, death resulting from paralysis of either the respiratory or cardiac centres in the medulla, or from both. (4) REMOTE LOCAL ACTION. In medicinal doses alcohol is almost entirely oxidized in the system, only about 3 per cent, passing out un- changed, the major portion by the lungs, the remainder by the kidneys and skin. This portion, however, includes ethereal and other complex bodies which are associated with alcohol in spirits and wines. The major portion of the alcohol proper is excreted as carbonic acid and water. During excretion it acts as a diuretic, and fluids such as beer and gin possess this action in a marked degree. It has also a remote local action as a diaphoretic. Medicinal Uses. — It is well known that alcohol is often prescribed indiscriminately in the treatment of diseases of the respiratory system, and much difference of opinion exists among authorities as to its beneficial effects or otherwise. In judging of the value of stimulants, just as of counter-irritants, no hard and fast rule can be laid down ; clinical experience alone can direct the prac- titioner when alcohol is indicated, and when its use can be dispensed with. The state of the pulse and heart, the general strength of the patient, his appetite and powers of assimilation, should be the chief guides in the employment of this agent. We are assured of the full effects of alcohol in our patients, which differ from human beings, in whom habit as regards this drug has a very decided influence on its Digitized by Microsoft® 332 VETERINARY THERAPEUTICS actions. But we must not forget that, in some instances, when alcohol is prescribed for animals in a palatable form, more of the agent finds its way into the system of the attendant than into the patient, and that this can be effectually guarded against by mixing some harmless drug with the alcoholic liquor. We shall notice the uses of alcohol under the following headings : (a) As a Stimulant. — In threatening death from cardiac failure, as in cases of haemorrhage, shock, etc., alcohol is especially indicated, being usually available, convenient, and rapid in its action. For such purpose either whisky or brandy should be administered to horses and cattle in full doses, varying from half a pint to a pint, slightly diluted with hot water, and combined with a rapidly- acting diffusible stimulant, such as a preparation of ammonia or sulphuric ether. For dogs from a quarter to half a wineglassful will be required, according to the size of the animal. (b) In fevers and acute diseases characterized by ex- haustion, alcohol judiciously employed is an agent of great therapeutic value. The indications in such cases are to prevent or make good the great waste of tissue, to sustain the heart and nervous system, which threaten to fail, to reduce the abnormal temperature, to aid digestion, and to supply a temporary food. These indications are well summed up by Dr. H. 0. Wood (' Therapeutics and Materia Medica ') as follows : ' Alcohol enables the system to stand the drain upon its vital powers, and at the same time to check such drain.' From our knowledge of the actions of alcohol, we see clearly that it fulfils all these indications, but we also infer that its indiscriminate use should be carefully avoided. It should be understood that alcohol is by no Digitized by Microsoft® ALCOHOL 333 means essential in every febrile affection. If the appetite remain fairly good and the pulse of sufiScient strength, we should rely on simple measures, with strict attention to nursing and to the details of hygiene. Besides the evil effects of the indiscriminate use of the drug, we have to consider that the constant administra- tion of drenches to the patient will tend to annoy him at a time when rest is urgently needed. At the same time, we ought to be careful not to delay prescribing alcohol until the system of the patient becomes weakened and debilitated by the disease. If the pulse be frequent and weak, with excessive temperature, dryness of the skin, Joss of appetite, etc., then alcohol will be indicated, and is likely to prove of benefit. In pneumonia, bronchitis, etc., it is usually in the second stage that alcoholic stimulants are indicated when inflammatory products are being absorbed. As respiratory affections in horses are mostly of an asthenic character, aggravated by enforced work during the primary stages and by unsanitary surroundings, we often find that at our first attendance alcoholic stimu- lants are indicated. In cases of that affection termed 'influenza,' often characterized by total loss of appetite and great debility in the early stages, the judicious administration of alcohol causes a return of the appetite and an improve- ment in the general appearance of the patients. In severe cases it is necessary to prescribe alcohol at intervals, as its effects are transient, the doses and the frequency of repetition being mainly determined by the condition of the patient. In some instances the doses must be repeated every two or three hours, and large amounts are tolerated apparently from the rapidity of Digitized by Microsoft® 334 VETERINARY THERAPEUTICS oxidation of the drug in the system. From two to three glasses of whisky every three hours may be required, and in cases characterized by extreme debility and exhaustion the administration should be continued at intervals during the night, as much harm is often done by leaving a patient all night without stimulants or necessary nourishment when the demands of the system require both. The amount of alcohol should be steadily decreased as there are signs of improvement in the patient, and during the period of convalescence we find it of advantage to change the stimulant to one containing a smaller per- centage of alcohol, such as strong ale. This also acts as a valuable tonic, and may be administered in doses of a pint twice daily combined with either vegetable or mineral tonics. In canine practice we also find alcoholic stimulants of great service. In eases of distemper, characterized by weakness, loss of appetite, etc., small doses of brandy, sherry, or port are indicated. In cases of diarrhoea, dysentery, etc., especially in young dogs, port wine is a valuable remedy, possessing both stimulant and astringent properties. (c) When a depressing agent exists in the system, such as certain poisons — for example, aconite, etc. — alcohol is indicated as an arterial and nervous stimulant to over- come the effects of the depressing agent. {d) In chronic diseases, attended by great debility and want of appetite, alcohol in small regular doses is indi- cated ; also in chronic disease of the heart, when natural hypertrophy fails and dilatation ensues. (e) In some forms of atonic dyspepsia, with a tendency to flatulence, alcohol is prescribed in different prepara- tions; it increases gastric secretion, and also acts as a carminative and antispasmodic. Digitized by Microsoft® ALCOHOL 335 Contra-Indications. — In cases characterized by cerebral excitement, with high arterial tension, such as phrenitis, meningitis, etc., also in cases of shock or injuries to the brain, stimulants should be withheld. External Uses. — As a stivmlant and refrigerant a solu- tion of alcohol is applied as a popular remedy to bruises and strains. It is largely employed as a solvent in phar- macy, also in the preparation of tinctures and extracts. Digitized by Microsoft® 336 VETERINARY THERAPEUTICS CHAPTEE VII. THE CAEBON COMPOUNDS— CoTO\. ; ol. eucalyptus, §i. ; vaseline, Jv. Mix. In canJcar of the ear in the dog it acts very beneficially, being applied directly in the form of dry powder. In cases of thrush, equal parts of iodoform and calomel form an efficient application, which should be introduced carefully into the cleft of the frog, until the discharge therefrom ceases. In cases of ozana, chronic nasal catarrh, etc., iodoform if3 introduced directly into the nasal cavities by means of an insufilator once a day, and often gives satisfactory results. lodol. A powder obtained by precipitating a moderately pure pyrrhol with iodo-iodide of potassium. This resembles iodoform in its actions and uses, but is devoid of odour, and non-toxic when applied to wounds. Aristol. A compound of iodine and thymol, resembles iodoform in its actions, but is said to be non-toxic. Paraffinum IVIolle. — Soft Paeaffin, Vaseline. A semi-solid mixture of the softer or more fluid members of the paraffin series of hydrocarbons, usually obtained by purifying the less volatile portions of petroleum. Uses. — Vaseline is not oxidizable, and hence cannot hecome rancid or irritant to the skin. It is extensively employed as a basis for ointments instead of lard, and is also useful as a lubricant and emollient application. Digitized by Microsoft® ACONITE 385 CHAPTEE IX. II. — THE ORGANIC MATERIA MEDICA. GROUP I.— THE VEGETABLE KINGDOM. The vegetable kingdom supplies a large number of medicinal agents, some being of great importance ; others, in consequence of their actions not being understood, are but seldom employed. To the latter only a passing notice will be given, while those agents whose value has been demonstrated by practical use iu the treatment of disease will be considered at length. We shall endeavour, as far as possible, to group together those drugs which possess a similarity of actions, and compare them whenever necessary, and thus assist the student to remember their indications and uses. This plan is preferable to arranging the agents according to their natural orders, or alphabetically. Aconiti Radix — Aconite Eoot. The dried root of Aconitum Napellus (monk's-hood). Aconiti Folia. The fresh leaves and flowering tops of Aconitum ■ Napellus. Preparations of Aconite Boot. Tinctura Aconiti (B.P.) — Tincture of aconite (British Pharmacopoeia), 1 in 8 of spirit. Doses. — Horses, 3ss. to 3i. ; cattle, 3i. ; sheep, n\_v. to n\_x. ; dogs, TTLii. to lT\_v. Small doses should be repeated at intervals of one or two hours, combined with salines or diaphoretics. Fleming's Tincture of Aconite is about four times as strong as the above, the doses for horses being TT^v. to ITLx. ; cattle, n^x. to TTLxx. ; sheep, TI|_ii. to ITl^iii. ; dogs, ITl ss. to ITtii. 25 Digitized by Microsoft® 386 VETERINARY THERAPEUTICS Aconitina — Aconitike. An alkaloid obtained from aconite root. It is not given internally, but externally is sometimes employed in the form of unguentum aconitinse — 1 to 55 of benzoated lard. Pulvis Aconiti (Folia) — Powdered Aconite. Dose.— Horses, 3i. to Jii. ACTIONS OF ACONITE. (1) immediate local action. Externally, aconite applied to the skin or exposed mucous membranes depresses the peripheral endings of sensory nerves, and subsequently paralyzes them. It can be absorbed by the skin. Internally, fall doses have a topical irritant effect on the stomach, causing slight pain and nausea, followed by vomition in dogs. It subsequently depresses the gastric nerves. (2) specific action. Aconite is rapidly absorbed from the stomach, and entering the blood, it passes quickly into the tissues. Medicinal doses given in close succession have a special action on the heart, the circulation, respiration, and temperature. They reduce the frequency, force, and tension of the pulse by acting on the nerves, and also by a direct action on the nervo-muscular structure of the heart itself. The blood-pressure is lowered, partly from cardiac, and partly from vaso-motor, depression. Bespiration is slowed, both from reduced circulatory force as well as direct depression of the respiratory centre. The shin is stimulated, perspiration is slightly in- creased, and temperature is lowered steadily. Digitized by Microsoft®- ACONITE 387 The kidneys are stimulated, and the fluids and solids of the urine are increased in amount. On the nervous system the specific action of aconite is that of a depressant. Authorities do not agree as to the exact manner in which the different portions of the nervous system are affected by this drug. Some state that it first depresses, then paralyzes, the sensory centres of the spinal cord, the peripheral nerve-endings being next affected, and finally the nerve-trunks. Others believe that the sensory nerves are affected from the periphery inwards, the spinal cord being secondarily acted on. The motor nerve-endings and nerve-trunks also become depressed, but the influence on these is less than on the sensory nerves. The brain is not directly affected, and even large doses do not remove consciousness, but may disturb it. Toxic Effects. — Aconite in toxic doses causes great disturbance of respiration, muscular weakness, and vascular depression ; the cardiac action becomes fre- quent, irregular, and gradually feebler, tending to cease in diastole. Death may occur from asphyxia, depending on paralysis of the respiratory centre ; but a very large dose may kill by syncope, due to sudden paralysis of the heart-muscle. Convulsions may precede death in some instances. In the horse, large doses cause frothing from the mouth, nausea, attempts at swallowing, followed in a variable period by attempts at vomition, accelerated respirations, and feeble pulse. Professor P. Smith, in experimenting with this drug, gave a pony 4 ounces of the tincture of aconite undiluted. In ten minutes there was slight frothing from the mouth, a gulping sound from the throat, as if making attempts to swallow, pulse weak and very compressible, and, Digitized by Microsoft® 388 VETERINARY THERAPEUTICS judging from the sound proceeding from the abdomen, there were increased peristaltic movements of the in- testines. In forty minutes the animal was pawing with one fore-leg, and in one and a quarter hours from the commencement there were distinct attempts at vomition, which were continued for three and a half hours after receiving the dose. The animal commenced to recover, and was in a normal condition in five and a half hours. Aconitine is a very active poison, even ^-g grain in- jected hypodermically producing serious symptoms in the horse. In horses destroyed by this alkaloid, the prominent symptoms noted were excessive salivation, grinding of the teeth, indications of pain, and violent tetanic convulsions. No alteration of temperature, nor any increased secre- tion from the skin, bowels, or kidneys, was noted. In dogs, large doses of aconite generally cause in five minutes painful vomiting and continuous retching, muscular exhaustion, and paralysis of the hind ex- tremities. In some instances death occurs with great rapidity. Antidotes. — In the dog, if seen immediately after the poison has been taken, emetics should be administered. Alcoholic or ammoniacal stimulants should be freely given, and ether used hypodermically, every means being adopted to assist in maintaining cardiac and respiratory action. (3) EEMOTB LOCAL ACTION. Aconite is excreted by the kidneys, increasing the solid and fluid portions of the urine. It probably also leaves the system by the skin. Medicinal Uses.— In acute febrile affections in sthenic patients, aconite judiciously prescribed is a valuable agent, acting as a vaso-viotor sedative, reducing cardio- Digitized by Microsoft® ACONITE 389 vascular excitement, and lowering abnormal tempera- ture. In the early stages of respiratory affections, it is pre- scribed in carefully regulated doses, in combination with the liquor ammonii aeetatis, and repeated every two or three hours. It is contra-indicated in eases characterized by debility, weakness of pulse, and in cardiac affections. Being a powerfully depressing agent, its effects require to be carefully watched, and, generally speaking, its use is not indicated in that affection termed influenza, as the system is in an already depressed condition. In laminitis, aconite is indicated, and gives very bene- ficial results in the early stages, combined with salines, such as the nitrate of potassium, and, administered at intervals of one or two hours, it tends to relieve pain, and reduces excessive cardiac action and temperature. In enteritis, it was recommended in combination with opium and camphor by the late Professor Robertson (' Equine Medicine '). In acute rheumatism, it relieves pain and reduces the pyrexia, being, combined with salines. In tetanus, it has been prescribed with variable success in the earlier stages, in the form of hypodermic injections of Fleming's tincture in from T(\_v. to TTl_x. doses. In chronic cough and broken wind, it acts as an efBeient palliative remedy, combined with arsenic, strict attention being also given to dietetics. For such purposes it may be administered in the form of powders, such as the pulvis aconiti folia, or in the form of the tincture, com- bined with the liquor arsenicalis. Externally, aconite is used as a local anodyne in rheumatic affections and swollen, painful joints, in the form of linirnent, combined with a small proportion of Digitized by Microsoft® 390 VETERINARY THERAPEUTICS chloroform. The ointment of aconitine may be similarly employed. The external use of aconite demands special care in consequence of the danger of absorption. Veratrina — Vebateine. An alkaloid or mixture of alkaloids, obtained from the dried ripe seeds of Cevadilla or Sabadilla — a Mexican plant. It is also present in small amounts in Veratrum album, popularly known as white hellebore, and in Veratrum viride, or green hellebore, both of which are allied to veratrine in their physiological actions. Doses. — Horses, grs. i.ss. to grs. ii. ; cattle, grs. ii. to grs. iv. By hypodermic injection. Actions.' — Externally, veratrine applied to the skin or mucous surfaces acts as a powerful irritant, and then depresses the nerves and vessels, terminating in loss of sensibility and vesication. Internally, full doses cause salivation and painful vomit- ing in dogs, violent purging, great muscular prostration, slow, feeble, or irregular pulse, shallow respiration, a lowering of temperature, spasmodic twitching of muscles, and finally collapse, death occurring from asphyxia. In horses, 5 or 6 grains administered caused saliva- tion, profuse sweating, muscular trembling, and violent contractions of the gastro-intestinal muscles, with efforts at vomition (Kaufmann). On the nervous system veratrine exerts a slight de- pressing influence, but has no marked action on the brain or spinal cord. The muscles are the structures chiefly acted on by the drug. It produces a remarkable lengthening of their contraction, and increases their force, so that the muscles appear to be in a state of tetanus ; but this condition really depends on a single contraction, and not on a Digitized by Microsoft® VERA TRINE 391 series of simple spasms. In larger amounts it causes weakness of the muscles, and finally paralysis. On the heart it produces similar effects as on the voluntary muscles ; it lengthens the contractions of the organ, thus reducing its frequency, larger doses causing irregularity, feebleness, and finally paralysis. The blood presstire is first raised, and then falls. Bespiration is first accelerated, and then slowed, being finally arrested through the centre, the muscles, and the vagus. The temperature is lowered, probably depending on circulatory depression. Medicinal Uses. — Veratrine has been recommended as an antipyretic for the same conditions as aconite, viz., acute febrile affections in sthenic subjects ; but its de- pressing influence on the system does not render its use either safe or advantageous. According to M. Cagny (' Precis de Therapeutique Vetdrinaire '), this drug has the power of stimulating the functions of the stomach in cattle, and is an agent of great value in cases of impaction, by causing the removal of a large portion of the gastric contents. It is ad- ministered in doses of 2 to 3 grains hypodermically, and may be repeated if necessary. This authority also states that veratrine resembles, to a certain extent, eserene, but that it has less action on the intestinal secretions, as compared with its influence on the peristaltic movements, and he recommends a combination of veratrine, eserene, and pilocarpine in the treatment of impaction of the colon in the horse. Staphisagriae Semina — Stavbsacrb Seeds. The ripe seeds of Delphinium staphisagria, or larkspur. Contains several alkaloids, the most important being delphinine and staph isagrine. Digitized by Microsoft® 392 VETERINARY THERAPEVTICS Actions and Uses. — Delphinine resembles aconitine in its actions, but is even more depressant to the vessels. Stavesacre is only used as a parasiticide, for the destruction of pediculi and acari. For such purposes one part of the bruised seeds is boiled for two hours with twenty to thirty parts of water, making up the latter to the original quantity. Strong preparations too freely applied, or absorbed from abraded surfaces, or licked by dogs, are liable to produce nausea and prostration. As an application for mange in the horse. Professor Williams recommends the following formula : R Pulv. delphini staphisagriae, jii. Adipis vel o!. palmae, gviii. 01. olivffi, p. Mix and digest at 100° in a sand-bath, and strain. For the destruction of lice, a decoction of stavesacre is very efficient, composed of one ounce of the powdered seeds to a pint of water, care being taken that the animals do not lick themselves for some time after the remedy is applied. Colchici Cormus — Colchicum Coem. The fresh corm of Colchicum autumnale, or the autunm crocus, dried and powdered for use. Doses. — Horses, 3ss. to 3i. ; cattle, 3i. to 3ii. ; dogs, grs. ii. to grs. viii. Eepeated twice daily in combination with salines. Colchici Semina — Colchicum Seeds. Preparation. Tinctura Colchici — Tincture of colchicum — 1 to 8 proof spirit. Doses. — Horses, gi. to gi.ss. ; cattle, Jii. ; dogs, IT^x. to TT|_xxx. Digitized by Microsoft® COLCHICUM 393 Actions. — The pbysiological action of colchicum is not clearly understood, hence its use in medicine is some- what empirical, and founded on the results obtained in the treatment of certain diseases. Given in a large dose it causes gastro-intestinal irritation, purging, cardiac depression, and an increase of the biliary secretion, its actions resembling to a certain extent those of veratrine. Its alkaloid, colchicine, enters the blood and tissues, and acts as a depressant on the central nervous system, large doses producing loss of sensibility and consciousness, and diminishing reflex excitability ; the peripheral sensory nerves become paralyzed, while motor nerves and muscles are unaffected. On the Kidneys. — It is said by some authorities to diminish the amount of urine, but to increase the quan- tity of urea and uric acid. Medicinal doses act as diuretics and cholagogues. While largo amounts may lessen the quantity of urine excreted, moderate doses increase both the flow and the solid con- stituents, a fact which is proved by clinical experience. Medicinal Uses. — In subacute' rheuinatism, colchicum is prescribed with benefit in combination with saline diuretics, its effects probably being due to its power of assisting the excretion of the morbid material through the kidneys. In lymphangitis it is also useful in combination with other agents, in virtue of its diuretic and cholagogue actions. In azoturia, when the urinary excretion is deficient, colchicum is indicated, and may be given with sweet spirits of nitre. In the secondary stages of pleurisy, and in rheumatic pericarditis, it is prescribed with iodide of potassium, and gives favourable results in many instances. Digitized by Microsoft® 394 VETERINARY THERAPEUTICS CHAPTBE X. THE VEGETABLE KINGDOM— Con^mien'. Opium. The juice obtained by incision from the unripe capsules of Papaver somniferum, the white poppy (grown in Asia Minor), inspissated by spontaneous evaporation (B.P.). The best variety of opium is the Smyrna, Turkey, or Levant ; this yields 10 to 12 per cent, of morphine. Preparations. (1) Pulvis Opii — Powdered Opium. Doses. — Horses, 3i. to 5ii. ; cattle, 3ii. to 3iii. ; sheep, grs. X. to grs. xxx. ; dogs, grs. ss. to grs. iii. These dosfs must be modified according to sizes and requirements. (2) Extractum Opii — Aqueous — 2 in 1. Doses. — Half the above. (3) Pulvis Ipecacuanhse Compositus — Dover's Powder^ Opium, 1 ; ipecacuanha, 1 ; sulphate of potassium, 8 (1 in 10). Doses — Horses and cattle, 5ii. to Jiv. ; dogs, grs. v. to grs. XV. (4) Tinctura Opii — Tincture of Opium, Laudanum — Opium, 1| ; proof spirit, 20. Contains 1 grain in 14J minims, or nearly 33 grains to the ounce. Doses. — Horses and cattle, gi. to giii. ; sheep and pigs, 5ii. to 5iv. ; dogs, ni_v. to TTl_xxx. Modified accord- ing to requirements. (5) Tinctura Camphorae Composita — Camphorated Tincture of Opium, 'Paregoric' — Opium, 40 grains; Digitized by Microsoft® OPIUM 395 benzoic acid, 40 grains ; camphor, 30 grains ; oil of anise, ^ fluid drachm ; proof spirit, 20 fluid ounces (1 in 240). Doses. — Similar to those of the tincture of opium. (6) Unguentum Gallee cum Opio — Opium, 32 grains ; ointment of galls, 1 ounce (1 in 14|). Incompatihles of Opium and its Preparations. — Acetate and subacetate of lead, salts of zinc, copper and arsenic, all astringent vegetable preparations, fixed alkalies and their carbonates, alkaline earths, and ammonia. Opium contains a large number of constituents, among which are many alkaloids and two organic acids. The most important alkaloids are morphine, codeine, the- baine. The chief organic acid is meconic acid, an agent of no therapeutical importance. The alkaloid morphine, in consequence of its insolu- bility, is employed in the form of different salts ; it is obtained from opium by complex chemical processes, the various salts depending on the acid which is used in the preparation of each. Morphinse Hydrocliloras — Hydrochlorate of Morphine — is prepared by precipitating morphine by ammonia, diffusing in water, dissolving in hydrochloric acid, and crystallizing out. It is the salt most commonly employed. Solubility. — 1 in 24 of water, readily in spirit. Incompatibles. — The alkaline carbonates, lime-water, salts of lead, iron, copper, mercury and zinc, liquor arsenicahs, and all astringent vegetable preparations. Doses. — Horses and cattle, grs. iv. to grs. x. ; sheep, gr. i. to grs. ii. ; dogs, gr. I to gr. J. For hypodermic injection, which is the most effective, the minimum doses mentioned should be employed at Digitized by Microsoft® 396 VETERINARY THERAPEUTICS first, the agent being rendered in a soluble form, as follows : Liquor Morphinse Hydrochloratis (B.P.)— 41 grains in 1 fluid ounce of a mixture of spirit, water, and dilute hydrochloric acid (1 in 100). Dose for dogs : J\\ v. to ITLx., hypodermically. For horses and cattle a stronger solution is more con- veni' nt, and may be prepared of the strength of 2 grains of morphine hydrochlorate to each 25 minims of solution. Tinctura CMoroformi et Morphinse — Chlorodyne. See p. 338. Morphinae Acetas — Acetate of Morphine. Solubility. — 1 in 2| in water, readily in spirit. Doses. — Similar to those of the hydrochlorate. Morpliinse Sulphas — Sulphate of Morphine. Solubility. — 1 in 24 of water, sparingly in spirit. Doses. — Similar to the above. Codeina — Codeine — is prepared from the ammoniacal liquors from which morphine has been obtained ; it is present in opium in the proportion of | to 1 per cent. Doses. — About four times those of morphine. ACTIONS OF OPIUM. These depend chiefly on morphine, and any differences in the actions of each will be noticed afterwards. (1) IMMEDIATE LOCAL ACTION. Authorities differ as to the action of opium on the unbroken skin, some stating that morphine cannot be absorbed therefrom, and hence that the local effect is slight, if any. Digitized by Microsoft® OPIUM 397 Others believe that it acts as a local anodyne when applied in the form of liniment or fomentation, made from the tincture and other preparations. Opium and morphine are readily absorbed from wounds, ulcers, and exposed mucous surfaces, acting as local anodynes thereon. Internally. — In the mouth opium diminishes the secre- tions, and is quickly absorbed from the mucous membrane. It causes dryness of this region, and a degree of thirst. 071 the Stomach. — Opium produces brief irritation of the nerves, and may cause nausea in the dog, but sensi- bility is quickly reduced, and appetite, gastric secretion, and digestive activity are diminished. On the Intestines. — Opium exerts a distinct sedative effect. It diminishes or arrests the sensible and iusensible im- pressions from the mucous membrane, and lessens the secretions. It renders the peristaltic action slower, or completely arrests it by stimulation of the sjAanchnics , which are the inhibitory nerves of the intestinal walls. In large doses opium is stated by some authorities to cause paralysis of the splanchnics, and thus to increase peristalsis. (2) ACTION ON THE BLOOD. Morphine does not enter the circulation as quickly as some other alkaloids, although traces of it are rapidly discovered in the blood. The full action of opium is thus comparatively slowly developed, and its local effects continue to be exerted even in the colon, where the morphine is gradually being absorbed. It is said that the red corpuscles are reduced in size indirectly, probably through depression of the circulation and a deficiency of oxygen. Digitized by Microsoft® 398 VETERINARY THERAPEUTICS (3) SPECIFIC ACTION. The principal action of morphine is exerted on the nervous system, although it has a physiological effect on all organs. On the cerebrum its effects vary greatly in individuals of the same species, as well as in those of different species. In man, where the cerebrum is highly de- veloped, opium usually causes brief excitement of the convolutions, followed by depression and the occurrence of sleep. In the horse, where there is less development of the higher brain-centres, but relatively more development of the loco-motor centres, and of the reflex centres of the spinal cord, opium exerts its primary stimulant effects on these lower centres, and in many instances, instead of producing sleep, it causes restlessness, involuntary move- ments, pawing with one foot persistently, and continuous walking round in one direction ; in large doses it may cause delirium, accompanied with frequent neighing, etc. In such instances even large amounts of the drug will fail to produce sleep, but rather tend to increase the excitement. In some cases opium in medicinal doses will exert anodyne and hypnotic effects, these differences probably depending on the susceptibilities of individual animals. According to Dr. H. C. Wood, the restlessness induced in some horses by opium and morphine is due to de- lirium, and not to spinal excitement. Buminants are usually affected by opium in a similar manner to horses. Dogs may show a preliminary period of excitement, but depression usually follows, and sleep occurs, not, however, profound, but may be accompanied by muscular twitchings and evidences of disturbed dreams. Digitized by Microsoft® OPIUM 399 The effects of opium on the cerebrum are probably due to a direct action of iTiorphine on the nerve-cells, and not on the cerebral vessels. In those instances in which it exerts hypnotic effects, the perceptive and sensory centres become depressed earlier and more profoundly than the vital centres in the medulla, this being a matter of great therapeutical importance with reference to the safety of the drug. The motor centres in the brain and spinal cord are stimulated by morphine, and reflex excitability is in- creased ; these effects are well marked in the horse in those instances where the exciting action of the drug predominates. When cerebral depression occurs, muscular weak- ness of central origin sets in, the motor nerves become paralyzed from the centres outwards, but muscular irritability is never completely lost. The sensory nerves of all organs of the body are de- pressed by opium. The sensory nerve-terminations have their functions lowered or arrested, so that common sensibility is reduced and pain cannot be originated. This peripheral anodyne effect, however, is secondary both in time and degree to the action of the drug on the sensory centres. The sensory nerve-trunks have their power of con- ductivity diminished, this effect still further preventing painful impressions being conveyed inwards. The hypodermic injection of morphine possesses a local anodyne effect on the peripheral sensory nerves and the nerve-trunks, as well as a central effect. 071 the vital centres of the medulla opium acts as a depressant. On the cardiac centre it causes primary excitation, followed by depression. Digitized by Microsoft® 400 VETERINARY THERAPEUTICS On the Heart and Circulation. — The heart is temporarily accelerated by opium, partly through the cardiac centre, and partly through an effect on its intrinsic ganglia. In fuller doses its action is slowed by stimulation of the vagus in the medulla, and in the heart itself. The cardiac vagus is next depressed or paralyzed ; but in consequence of the intrinsic cardiac ganglia being simultaneously depressed, acceleration of the heart is impossible, so its action becomes infrequent and feeblr-. Death rarely occurs from sudden cardiac failure. The vessels become dilated through the vaso motor centre, but they are not directly influenced by the drug either in their muscular coats or their peripheral nerves. On Bespiration. — Opium is a powerful depressant ; the respiratory centre is depressed, and the respiratory movements become sup rficial and irregular ; the afferent nerves of breathing — i.e., the pulmonary branches of the vagus — are also depressed, so that reflection is dulled at its origin, and cough, spasm, and other reflex respiratory acts are rendered less liable to occur, or may be alto- gether arrested. The bronchial secretions are diminished by the action of the drug on the glands. In toxic doses the respiratory centre becomes para- lyzed, and death occurs from asphyxia. On the Liver. — Opium interferes with the biliary and glycogenic functions, and in that affection termed diabetes mellitus it diminishes the amount of sugar in the urine to a marked extent. It reduces the activity of hepatic and general metabolism, and diminishes the amount of urea, and probably of carbonic acid, excreted. The temperature temporarily rises, and then falls, apparently varying with the blood-pressure. The pupil of the eye is dilated in the horse, probably Digitized by Microsoft® OPIUM 401 from some effect of the drug oa the basal ganglia ; in the dog it is contracted while the animal is asleep, or narcotized as a result of the action of the drug. (4) EBMOTE LOCAL ACTION. Morphine leaves the system by most of the secretions, but especially in the bile. Its excretion commences rapidly, but may not be completed for a considerable period ; it is found in the urine, mainly unchanged. It diminishes the quantity of urine, and in large doses may suspend the action of the kidneys. Morphine in passing through the skin is said by some authorities to act as a diaphoretic ; but this effect is not observed in medicinal doses. It is also excreted in the milk, which necessitates caution in prescribing the drug to animals nursing their young. ACTIONS OF THE PEINCIPAL ALKALOIDS OF OPIUM. 1. Morphine. — As already mentioned, the action of opium depends chiefly on morphine, so that the description just given will apply to both; there are, however, a few points of difference which must be noticed. {a) Morphine in its pharmacopoeial preparations is more readily absorbed, and acts quicker, than opium, while the effects of opium are more lasting, and its immediate local action on the intestines is more marked. (h) Morphine is of definite composition, while the crude drug is often variable. It can be readily ad- ministered by hypodermic injection, while dyspeptic 26 Digitized by Microsoft® 402 VETERINARY THERAPEUTICS and constipating effects are less marked than in the case of opium. (c) Morphine has a more sedative influence than the entire drug, as several of the constituents of the latter possess, more or less, convulsant action, such as thebaine, codeine, narcotine. As a rule, morphine is preferred to opium, except in cases of intestinal affections, such as diarrhoea, dysentery, etc., where the latter reaches the bovyel directly, and exerts its immediate local action thereon. 2. Codeine is generally believed to excite the spinal cord more than morphine, and to depress the convolu- tions less. It reduces the amount of sugar in diabetes to a marked degree. According to M. Cagny (' Precis de Therapeutique Vet6rinaire), codeine is an anodyne less narcotic than morphine, and does not cause so marked a period of excitation in its action on nervous horses. He prefers codeine to morphine for the various purposes of an anodyne. 3. Thebaine, or Paramorphine, present to the extent of one half per cent, in opium, stimulates the motor tract of the spinal cord, and acts like strychnine, producing muscular rigidity and convulsions. We are not aware of its employment for therapeutical purposes. Toxic Effects of Opium and Morphine. — Horses resist the toxic effects of opium and morphine to a great extent. In the majority of instances large doses produce excitement, restlessness, muscular tremors, dilatation of the pupils, continuous walking in a circular direction, shaking of the head, profuse sweating, delirium ; these effects may continue for a long period, and are usually succeeded by profound depression and nausea. Digitized by Microsoft® OPIUM 403 According to Dr. H. C. Wood (' Materia Medica and Therapeutics '), 100 grains of acetate of morphine killed a horse with convulsions in three hours. In the dog large doses of opium or morphine generally cause nausea, staggering, unsteady gait, muscular twitch- ing, clonic spasms, stertorous breathing, stupor, and death from asphyxia due to paralysis of the respiratory centre. Antidotes. — In the dog emetics should be resorted to, and preparations of ammonia prescribed to promote cardiac and respiratory action. In all animals the occurrence of coma should be pre- vented by artificial respiration and keeping the patient moving about. Small doses of atropine, administered by hypodermic injection, in a judicious manner, are recommended to maintain the cardiac and respiratory functions. Comparison of the Actions of Opium and Belladonna. — As morphine and atropine are frequently combined as anodynes in the form of hypodermic injections, it will be necessary to briefly compare their actions. In some respects the action of morphine is opposed to that of atropine. Thus, atropine in medicinal doses has a sedative effect on the cerebral convolutions. It stimulates the respiratory centre, and by depressing the inhibitory branches of the splanchnics causes relaxation of the intestines. By combining the two agents we find that one may prevent or relieve certain effects of the other when employed as anodynes. Thus, atropine prevents the nausea, depression, dyspepsia, and constipation which are apt to occur after the administration of morphine. Medicinal Uses. — As an anodyne opium and its alkaloid Digitized by Microsoft® 404 VETERINARY THERAPEUTICS morphine are frequently employed in cases where the rehef of pain is the primary indication of treatment. Such cases are very numerous, and depend on various pathological conditions. In the horse, as we have already noticed, opium and morphine act as excitants to the nervous system in many instances, and hence do not produce anodyne effects in as satisfactory a manner as in dogs or human beings. As a rule, if the first dose of opium or morphine fails to give relief, further doses will only tend to cause excitement. The combination with atropine, according to our experience, does not tend to overcome this exciting effect, and the most reliable agent to combine for this purpose is chloral hydrate in doses of one ounce, re- peated until hypnotic effects are produced. In many cases of violent abdominal pain, such as occurs in volvulus, acute enteritis, gastritis, etc., opium and morphine fail entirely to give relief, and we now .employ cannabis indica as an effectual anodyne and hypnotic in these conditions (see p. 408). Many of such cases are of a fatal nature from the commencement ; but this should not deter us from giving the patients relief from the agonizing pain which is pre- sent. As a rule, the hypodermic injection of morphine gives more reliable effects than opium administered by the mouth, for reasons already stated. Powdered opium given in the form of bolus takes a long time to act in the horse, and an important point to remember is, that in affections of the alimentary canal absorption is retarded, and ;pain affords great resistant power to the action of the drug, which appears to ex- pend itself on the morbid process. From the latter fact we learn that the doses of opium or morphine must be Digitized by Microsoft® OPIUM 405 regulated according to the demands of the case, and that insufficient amounts are of no practical value ; pain must be relieved, or it will hasten fatal results. As an antispasmodic, the tincture of opium is em- ployed in the treatment of intestinal colic, and is combined with the spiritus setheris nitrosi for this pur- pose. In gastritis, in all patients, the preparations of opium are useful for relieving irritability, pain, and spasm, and giving the inflamed part rest. In diarrhcea, after the administration of a laxative, to remove the probable cause of the affection, some pre- paration of opium is indicated when the intestines remain irritable and relaxed. In such instances the tinctura chlorof ormi et morphinae (chlorodyne) is very useful, and may be administered in starch or flour gruel, and combined with an antacid. In dysentery opium allays pain and straining, and may be administered with astringents, such as tannic acid, ipecacuanha, acetate of lead, etc. In enteritis, peritonitis, metritis, the hypodermic in- jection of morphine is largely employed as an anodyne, and, as already mentioned, it is advisable to administer in addition a hypnotic such as chloral hydrate, so as to avoid the exciting effects of the morphine. In certain affections of the respiratory system opium may be indicated, but great discrimination is necessary in its employment. In the primary stages of pleurisy, accompanied by severe pain in the chest and harassing cough, opium judiciously prescribed gives beneficial results in combina- tion with the other details of treatment. In cases of cough depending on reflex irritation, or on excessive irritability of the nerves and centre, opium is Digitized by Microsoft® 406 VETERINARY THERAPEUTICS indicated, and may be given with benefit in the form of the tinctura camphorse composita. In tetanus the hypodermic injection of morphine com- bined with atropine has been employed with a variable degree of success. In premature labour pains, m post-partum hemorrhage and straini7ig, and in cases of eversion of the uterus, bladder, or vagina, opium or morphine are administered with benefit as sedatives and antispasmodics. In cases of intestinal hemorrhage opium is of great value, as it arrests the movements of the bowel, and has a sedative effect on the circulation. In such cases it should be combined with acetate of lead or preparations containing tannic acid. In diseases of the heart, in which pain and distress are prominent symptoms, opium judiciously admin- istered is beneficial ; but as it is a dangerous cardiac depressant, other anodynes, such as belladonna, are preferred. In diabetes mellitus, occasionally met with in dogs, but rarely in horses, opium or codeine administered twice daily gives favourable results. As an antidote to strychnine - poisoning, morphine has the power of antagonizing the muscular spasms ; and Professor P. Smith records an instance of a dog poisoned with strychnine, and so convulsed that recovery seemed impossible, but after five grains of morphine had been injected hypodermically the muscular spasms ceased, the animal slept for twenty-four hours, and recovered, Contra-Indications of Opium and Morphine. — In con- gestive and inflammatory affections of the brain. In diseases of the respiratory organs with shallow, em- barrassed breathing, and a tendency to death from Digitized by Microsoft® OPIVM 407 asphyxia, opium or morphine is apt to still further depress respiratory function. In cough and respiratory distress, with abundant secretion, as in the bronchitis of weak or debilitated subjects, opium leads to retention and inspissation of the products, aggravation of the cause, and a tendency to asphyxia. In renal disorder or disease, if the action of the kidneys be deficient, opium tends to increase this condition, and there is a probability of the retention and accumulation of morphine in the system. Externally , opium is employed as a topical anodyne in the form of liniment, prepared by mixing equal parts of the tincture of opium and soap liniment. In cases of eversion of the uterus, vagina, or bladder, the parts are washed with a solution of opium and belladonna before being returned to their normal positions. In neemorrhoids, opium is useful applied in the form of the unguentum gallse cum opio. Apomorphins Hydrochloras — Hydeochloeate of Apomoephinb. Prepared by heating morphine or codeine in sealed tubes with hydrochloric acid. Prefaratio7i. Injectio Apomorphinee Hypodermica — 2 grains dissolved in 100 minims of camphor-water. Dose. — Subcutaneously for dogs, n\_ii. to m v. Actions and Uses. — Apomorphine is the quickest and most reliable of all emetics ; it acts upon the vomiting centre, and but slightly on the stomach, being mainly an indirect emetic. Digitized by Microsoft® 408 VETERINARY THERAPEUTICS It is employed in canine practice in doses of gr. -^-j to gr. j-V hypodermically, and gr. J^ to gr. \ by the mouth. Its effects are produced in from 6 to 20 minutes, con- sisting of moderate nausea, repeated vomiting, and the disturbances of the respiratory and circulatory organs, usually caused by emetics. It is stated not to cause local irritation of the stomach, and to leave little or no after-effects. Small doses (gr. J„) are expectorant. , Apomorphine administered to the horse produces no attempts at vomition, but causes alarming symptoms of cerebral excitement. Cannabis Indica — Indian Hemp. The dried flowering or fruiting tops of the female plEtnts of Cannabis sativa, grown in India, and from which the resin has not been removed. It contains a glucoside, cannabin ; an active principle, cannabinon ; a volatile alkaloid, cannabinine ; another alkaloid, teiano- cannabine ; and a volatile oil, cannabene. Preparations. Extractnm Cannabis Indicse — Alcoholic — 6 in 1. Doses. — Horses and cattle, §ss. to gi. ; dogs, gr. ^ to gr. i. Tinctura Cannabis Indicse — 1 of extract to 20 of spirit. Dose for dogs, Tr\ v. to n\ xx. Actions. — The physiological effects of the active principle and alkaloids of cannabis indica have not been fully determined. Tetano-cannabine is said to be a convulsant. The extract is the preparation concerning which we have some definite knowledge, and which is generally employed in practice. Digitized by Microsoft® INDIAN HEMP 409 Cannabis indica acts as a hypnotic and anodyne when administered in sufficient doses. It does not produce the intoxicating effects in veterinary patients recorded as occurring in man, and no exciting action is noticed as the primary effects of the drug. Individual susceptibility and a variable composition of the drug probably account for the diiferences sometimes observed in its action on horses, but in the majority of instances, if a suitable dose be administered, marked hypnotic and anodyne effects will be produced. Cannabis indica resembles opium in its actions to a certain extent, but instead of the cerebro-spinal excitement induced by the latter drug, we have a condition of profound sleep, probably depending on the effects of the agent on the cerebrum. Administered in doses of from half an ounce to one ounce of the extract, it commences to act in from twenty minutes to half an hour ; the horse assumes a sleepy appearance, the eyelids droop, the head may be shaken in a listless manner, the animal usually retains the standing posture, with the head in the corner of his stall ; as the drug continues to exert its action, a snoring sound is heard during inspiration, and the animal appears unconscious to surrounding influences. These effects may continue for a period of from ten to twelve hours, and gradually pass off ; but if the dose has been excessive, or if the animal be particularly susceptible to the action of the drug, an alarming state of narcosis may be produced. The lips are retracted, the tongue hangs from the mouth, the pulse is weak and accelerated, respirations hurried, shivering fits occur at intervals, there is partial loss of control over the hind extremities, the animal keeps its head in a corner, and if disturbed tends to return to its former position, a Digitized by Microsoft® 410 VETERINARY THERAPEUTICS flow of frothy saliva issues from the mouth, the penis may be pendulous. Even in this condition the animal may attempt to feed on a bran-mash, but the lips are usually worked in a semi - unconscious manner, and little or nothing is swallowed. This state of narcosis may continue for an indefinite period, but after the administration of diffusible stimulants it gradually passes off, with but little degree of nausea or loss of appetite, and no inter- ference with the action of the bowels or kidneys. Even medicinal doses will in some horses produce an apparent loss of control over the hind extremities, but this gradu- ally passes off without any untoward effects. In man the drug is stated to produce a similar effect, and in addition a partial auEesthesia of the limbs occurs after full doses. We have no evidence of the toxic effects of cannabis indica, and, according to Professor P. Smith, even large doses will not cause death in the horse, although a very profound state of narcosis is induced. Medicinal Uses. — In consequence of its marked hypnotic effects, in addition to its anodyne action, ^ cannabis indica is an agent of very great value fo'r the relief of acute pain in horses, irrespective of its origin. As we have already stated, opium or morphine will fail to give relief in many cases of violent abdominal pain, in consequence of acting as cerebro-spinal excitants, even when large doses have been administered. In such instances cannabis indica will give relief ; its effects are reliable, and it does not produce the extreme nausea which occurs after opium or morphine. Even in cases of a fatal nature from the commence- ment, it gives the patient ease from the uncontrollable agony which he is suffering. Digitized by Microsoft® INDIAN HEMP 411 Professor P. Smith first directed the attention of the profession to the value of this drug as an anodyne and hypnotic for the horse, and clinical experience amply justifies the high opinion which he held of it. It is necessary to obtain a reliable preparation, and a proper dose should also be administered, the amount usually recommended in text-books being iu our experi- ence useless. It is best administered in the form of bolus, the average dose being half an ounce ; but in some instances one ounce may be necessary. Should there be any indications of a recurrence of pain, the drug should be repeated until hypnotic effects are produced. In cases where profound narcosis occurs for a lengthened period, either from individual susceptibilities or from excessive doses of the drug, it can be overcome by the administration of diffusible stimulants or the hypodermic injection of ether. In tetanus cannabis indica has been employed with variable success, and may be administered in the form of electuary placed between the molar teeth. hi chorea in dogs, it is highly recommended by some practitioners for tranquillizing the involuntary spasms which occur in this affection. It is probable that, as the actions of cannabis indica are more perfectly understood, its medicinal uses will be more extensive. One difficulty at present consists in obtaining preparations of a definite degree of strength. Coca— Coca. The dried leaves of Erythroxylon coca, a shrub from South America. Coca leaves contain about 0'2 per cent. of an alkaloid, cocaine. Digitized by Microsoft® 412 VETERINARY THERAPEUTICS Preparation. Cocainse HydrocMoras — Hydroohlorate of Cocaine. Prepared by a complex process from the crude drug. Actions and Uses. — A solution of the hydrochlorate of cocaine, when applied to an exposed mucous surface, or injected hypodermically, paralyzes the sensory nerves and contracts the vessels of a part. It thus produces local ancesthesia and ancemia. This condition may last for fifteen minutes or longer, accord- ing to the strength of the solution employed. Internally, coca acts as a stimulant, tonic, and restora- tive, when given in small doses. In full doses it causes great muscular restlessness and excitement, the brain, medulla and cord are powerfully stimulated from above downwards, and convulsions of cerebral origin occur. Toxic doses paralyze the posterior columns of the spinal cord and the peripheral sensory nerves; and finally paralyze the central nerve-centres, causing death from asphyxia. In horses doses of 60 to 80 grains, injected subcu- taneously, cause restlessness, excitement, salivation, dilatation of the pupil, effects which disappear in about two hours. Dogs are very susceptible to the action of cocaine, and hence great care is necessary to avoid strong solu- tions in employing this agent as a local anaesthetic. If an excessive amount be absorbed, it quickly pro- duces muscular spasms, epileptic fits, the animal rolling about and champing the jaws, with great salivation; clonic spasms occur, and death in a short time from asphyxia. The chief use of cocaine is as a local ancesthetic in Digitized by Microsoft® COCAINE 413 minor surgery, especially in that of the eye, throat, etc. A 4 or 5 per cent, solution is employed in ophthalmic surgery, being applied once or twice before operation at intervals of a few minutes. Its action commences in from three to five minutes, and increases in from ten to twenty minutes, usually disappearing within half an hour. In cases of iritis and ulceration of the cornea a solution of cocaine proves a very useful application. Foreign bodies embedded in the cornea are removed with facility after the application of a solution of cocaine to the part. Cocaine is largely employed for the production of local anaesthesia, in the removal of tumours, etc. The strength of the solution may vary from 5 to 20 per cent. The 5 per cent, solution is most commonly used ; it should be freshly prepared, and, in the case of large growths, from ten to twenty drops are injected at each of three or four points underneath the skin, and into the part to be removed. In neurotomy a hypodermic injection of from twelve to fifteen drops of the solution at the points of operation removes sensation from the skin, subcutaneous tissues, and the nerve-trunks. In firing it has also been em- ployed with success. Digitized by Microsoft® 414 VETERINARY TBERAPEOTICS CHAPTEE XI. THE VEGETABLE KINGDOM— CoHiimierf. Belladonnas Folia — Belladonna Leaves. The fresh leaves, with the branches to which they are attached, of Atropa belladonna (deadly nightshade) ; also the leaves separated from the branches and carefully dried, gathered when the fruit has begun to form, from wild or cultivated British plants. Doses. — Horses and cattle, §ss. to §i. ; dogs, grs. v. to grs. X. Belladonnas Radix — Belladonna Eoot. The root of Atropa belladonna, carefully dried. Preparations. Extractum Belladonnse — a green extract — 4 from 100 oi fresh leaves. Doses. — Horses, 3i. to 5ii. ; cattle, 3ii. to 3iii. ; sheep, grs. X. to grs. xx. ; dogs, gs. ss. to grs. iii. Extractum Belladonnse Alcoholicum. — A spirituous and aqueous extract ; this is about four times the strength of the green extract, and is prescribed in one quarter of the doses of the latter. Tinctura Belladonnae — 1 of dried leaves in 20 of proof spirit. Doses. — Horses, jss. to gi.ss. ; cattle, §ii. ; sheep, 5i. ; dogs, ni_v. to IT^xx. Glycerinum Belladonnse — Equal parts of extract of belladonna and glycerine. Doses. — Double those of the green extract. Unguentum Belladonnse — 1 of the alcoholic extract to 9 of benzoated lard. Linimentum Belladonnse — 1 ounce to IJ ounces of spirit with -^fj of camphor. Digitized by Microsoft® BELLADONNA 415 Atropina— Ateopine. An alkaloid obtained from belladonna root. Atropinae Sulphas — Sulphate op Ateopine. Prepared by dissolving atropine in dilute sulphuric acid and water and evaporating. Solithility — 1 in 4 of water. Incompatibles. — Caustic alkaloids, which decompose it. Morphine, physostigmine, and strychnine are in various respects and degrees physiological antagonists. LicLuor Afcropinae Sulphatis (B.P.) — 1 in 100 with camphor-water. Contains 4 grains to the fluid ounce. Doses. — Of the liquor atropinae sulphatis (B.P.) : horses and cattle, 3i. to sii. ; dogs, ni_i. to TTl^iv. Given by the mouth. Administered by hypodermic injection : horses and cattle, TTl_xii. ( = iV grain) to ni_xxiv. ( = i grain); dogs, nT_i. to TTl^ii. ( = gr. t4^ to gr. ^-^). Homatropinae Hydrobromas. The hydrobromate of an alkaloid prepared from tropine. Tropine is obtained from atropine. This resembles atropine in its actions, but is less per- sistent in its effects on the eye as a mydriatic. (1) IMMEDIATE LOCAri ACTION. Externally, belladonna and atropine in the form of aqueous suspension or solution are not absorbed by the skin, but if combined with alcohol, camphor, glycerine, etc., the atropine is readily conveyed through the epidermis. It can be absorbed from exposed mucous membranes and from inflamed or abraded areas of skin. Belladonna depresses the sensory nerve-endings, and thus acts as a local anasthetic and anodyne. Digitized by Microsoft® 416 VETERINARY THERAPEUTICS It contracts the bloodvessels and then relaxes them, and reduces the activity of motor nerve-filaments to underlying muscles. It also depresses any special nerve- endings with which it may come in contact, such as the nerves of the sudoriparous and mammary glands. Applied to the eye, it causes dilatation of the pupil, as well as when given internally. Internally, it causes dryness of the mouth and throat, which action is, however, a specific one. In the stomach it has a slight anodyne effect, while its action on the intestines is also a specific one, to be presently described. (2) ACTION ON THE BLOOD. Atropine enters the blood rapidly, and leaves it for the tissues, without producing any appreciable effects on the former. (3) SPECIFIC ACTION. Atropine reaches the different tissues quickly, pro- ducing marked effects on different portions of the system. A moderate dose causes dryness in the mouth and throat, with slight difficulty in swallowing ; the pupils are dilated, the bowels may become relaxed, and the pulse is reduced in frequency. Larger doses cause a frequent pulse, restlessness, accelerated respirations, disorder of vision, irregular movements with delirium, and finally coma. We shall now proceed to analyze these phenomena. On the ConvohUions of the Cerebrum. — Belladonna acts as a depressant in medicinal doses ; in large doses it may produce delirium. On the Spinal Cord. — It first slightly increases, and then diminishes, reflex irritability, but it does not possess a powerful action on this region. Digitized by Microsoft® BELLADONNA 417 On the Medulla Oblongata. — Belladonna produces marked effects on the vital centres. It stimulates the respiratory centre in a direct manner, causing more frequent and deeper respiratory move- ments, while toxic doses cause paralysis of this centre. The cardiac centre is temporarily stimulated, causing a primary slowing of the action of the heart. The vaso-motor centre is first stimulated, and then depressed. The sensory nerves are depressed, specifically as well as locally. The motor nerves have their irritability diminished; but this is not lost except after large doses. The voluntary muscles are unaffected by the drug. On special efferent nerve-terminations belladonna exerts marked depressing effects : (a) It paralyzes the endings of the third nerve (motor oculi) in the sphincter of the pupil and in the ciliary muscle, causing dilatation of the pupil and disturbance of accommodation. This effect is believed to be purely local in its cause, and, according to some authorities, the sympathetic is slightly stimulated. (b) It paralyzes the terminations of the chorda tympani in the submaxillary gland, the effects being an arrest of saliva, and dryness of the mouth and throat ; probably the mucous glands of the mouth are also paralyzed. (c) It depresses the terminations of the sudoriparous nerves in the sweat glands, and thus acts as a powerful anhidrotic, diminishing the amount of perspiration to a marked degree. (d) It paralyzes the lacteal nerve-terminations, and arrests the secretion of milk (if present). (e) It briefly stimulates the ends of the vagus in the heart, but qaicklj paralyzes them. (/) It paralyzes the terminations of the vagus in the Digitized by Microsoft® ^'^ 418 VETERINARY THERAPEUTICS bronchial walls, also the afferent branches of the vagus in the same parts. (g) It depresses the inhibitory branches of the splanchnics in the intestinal ivalls, thus causing relaxation of the bowels and increased peristaltic movements. Its action on the ganglia, plexuses, and muscular coat is not definitely known. On the heart and circulation belladonna exerts marked actions. The action of the heart is sloiued temporarily by stimulation of the cardiac centre, as already mentioned, and also by stimulation of the terminal ends of the vagus in the heart. The pulse next rises iji frequency , due to paralysis of the terminal ends of the vagus, but the force of the systole is not reduced after moderate doses. Toxic doses depress the intracardiac ganglia, and finally paralyze the heart muscle, death occurring from cardiac failure, with the ventricle in diastole. According to some authorities, death results from asphyxia, due to paralysis of the respiratory centre. On the circulation belladonna produces effects by its action on the vaso-motor centre. The primary effect of the drug, viz., the stimulation of this centre, causes contraction of the systemic arteries, and a temporary rise of the blood-pressure ; this coincides with the cardiac acceleration. The secondary effect of full doses is to depress the vaso-motor centre ; this causes relaxation of the peripheral vessels and a lowering of the blood-pressure, and if this be extreme, it coincides with the paralysis of the cardiac ganglia and muscle, and contributes to the final arrest of the circulation. On Bespiration. — Owing to its powerful stimulating Digitized by BELLADONNA 419 effect on the respiratory centre, already mentioned, the respiratory movements become more frequent and deeper ; toxic doses paralyze this centre. The tension of the muscular coat of the bronchi is diminished and the air current facilitated, due to paralysis of the terminations of the vagus in the bronchial walls. Sensibility and reflex action in the same parts are diminished, i.e., dyspnoea and cough, this effect de- pending on paralysis of the afferent branches of the vagus. The body temperature is temporarily raised by moderate doses, but it falls with the failure of the circulation after large doses. Toxic Effects — In the Horse. — The experiments of Hertwig demonstrate that large doses of belladonna cause dulness, uneasiness, dilated pupils, loss of appe- tite, tympanitis of the stomach and intestines, pulse quick, small and gradually imperceptible, respirations short, quick and accompanied by flapping of the nostrils. No hypnotic effects were produced ; some of the cases exhibited imperfect power of moving the hind extremities, others showed symptoms of abdominal pain. Some cases terminated in thirty to fifty hours after the first dose, but in others the symptoms gradually abated. Six ounces of the dried root usually proved fatal. Antidotes. — The administration of diffusible stimu- lants, alcohol, ammonia, etc. ; artificial respiration if necessary. In the dog, emetics should be early resorted to. Lime-water is believed to be destructive to atropine, and has been recommended as an antidote. As atropine is rapidly eliminated by the kidneys, the catheter should be employed to remove the urine, which Digitized by Microsoft® 420 VETERINARY THERAPEUTICS is often retained in poisoning by belladonna. The hypodermic injection of pilocarpine is also recommended, being to some extent a physiological antagonist. (4) BBMOTE LOCAL ACTION. Atropine is rapidly excreted in the urine in an un- changed condition. It acts as a diuretic, increasing the urea, phosphates, sulphates, and water of the urine. In its passage through the ureters, bladder, and urethra it exerts remote local anodyne effects. Medicinal Uses. — In affections of the respiratory organs belladonna is frequently employed, in consequence of its soothing effects on the afferent and efferent nerves of the bronchi, its stimulating action on the respiratory centre, and its power of abating excessive mucous secretion. In pharyngitis, laryrigitis, and bronchitis it relieves spasm and irritable cough, renders deglutition easier, and may be administered in the form of electuary in such cases. In asthma it has been employed with success in both horses and dogs. In some forms of cardiac affection belladonna is believed to relieve cardiac pain and palpitation, being always preferred to opium for such cases. Its effect is probably an indirect one, referable to frequent emptying of the ventricles, lowering of the vascular tension, and prevention of distension of the heart, without diminish- ing cardiac force. In gastritis in all patients belladonna is a very valuable agent. In cattle it may be combined with sodse bicarb, and ol. lini, and gives beneficial results in cases of inflammation of the abdomasum. In gastritis and gastro-enteritis in dogs it is recom- Digitized by Microsoft® BELLADONNA 421 mended by Professor "Wild, Eoyal Veterinary College, in combination with carbolic acid, and alternated with liq. plumbi diacet. {Veterinarian, August, 1894). In enteritis it is combined with opium, or in the form of hypodermic injection composed of atropine and morphine. In puerperal eclampsia in cows it has been employed with marked success. In tetanus belladonna has been extensively prescribed in doses of 3i. to 3iii. of the extract placed between the teeth several times a day, and is a favourite agent with many practitioners in the treatment of this usually fatal affection. It is also applied locally if any wound exist. In cases of irritation of the bladder, rectum, or uterus, belladonna is both prescribed internally as well as employed in the form of injection. In constriction of the cervix uteri, which may be pre- sent in cases of delayed parturition, the extract of belladonna is applied locally, and gives beneficial results, overcoming the rigid and unyielding condition of the part. Belladonna is sometimes combined ivith purgatives, as it assists their action and lessens the tendency to irrita- tion of the intestine. Externally, belladonna is extensively employed in the treatment of mammitis or garget in all patients. It checks the secretion of milk, reduces inflammation and pain, relieves tension, and tends to arrest impending abscess. Even when it fails to prevent suppuration, it limits the abscess and subdues the pain. For such purpose it is best applied in the form of ointment com- posed of — glycerinum belladonnae 1 part, unguentum althsBse 2 parts, lanoline 2 parts. This is rubbed into the part after frequent fomentation with hot water. Digitized by Microsoft® 422 VETERINARY THERAPEUTICS In affections of the eye, atropine sulphate is employed locally as a solution containing from 2 to 4 grains to the ounce of distilled water. It prevents or breaks down adhesions in iritis, and may be alternated with myotics, such as physostigmine. In keratitis and conjunctivitis it reduces inflammatory action and relieves pain. In lesions of the cornea and in perforating uher atropine lotion gives satisfactory results, and may be combined with cocaine. In wounds and injuries to the eye belladonna should be applied around the region, as well as the solution of atropine applied to the organ itself. In specific ophthalmia, the solution of atropine is very useful during all stages of the affection, when employed in conjunction with constitutional treatment. In examinations of the eye with the ophthalmoscope, atropine is employed to dilate the pupil, and so assist in the detection of cataract. In wounds accompanied by extreme pain, such as punctured wounds of the feet, the appUcation of the extract of belladonna with glycerine gives marked relief, along with the judicious employment of poultices. In deep fissim-es of the heel, seen as a sequel to grease in the horse, accompanied by excessive lameness and pain, the application of the glycerinum belladonna to the part gives beneficial results. Hyoscyami Folia — Hyoscyamus, ob Henbane Leaves. The fresh leaves and flowers, with the branches to which they are attached, of Hyoscyamus niger, also the leaves separated from the branches and flowering tops, carefully dried. Digitized by Microsoft® HYOSCYAMUS 423 Preparations. Extractum Hyoscyami — A green extract from the fresh plant — 20 in 1. Doses. — Horses and cattle, 3i,ss. to 3iii. ; dogs, grs. v. to grs. X. Tinctura Hyoscyami — 1, dried, in 8 of proof spirit. Doses. — Horses and cattle, §i. to gii. ; dogs, IT(_xv. to 5i. Hyoscyamine. — A crystalline alkaloid obtained from hyoscyamus, usually prescribed as a neutral sulphate. Doses. — Horses and cattle, gr. i. to grs. iii. ; dogs, gr. -^V to gr. Jjy. Hyoscine. — A syrupy alkaloid forming salts such as the hydrobromate and the hydriodide. Actions and Uses. — Hyoscyamus closely agrees with the actions and uses of belladonna ; the following dis- tinctions, however, merit attention : (a) The pharmaceutical preparations of the drug are weaker than those of belladonna, and hence must be given in larger doses. (6) The secondary or calmative effects on the convolu- tions are more rapid and pronounced with hyoscyamus, the sedative action probably depending on the hyoscine. (c) Hyoscyamus possesses more marked laxative and carminative effects on the intestine. (d) It possesses a more decided remote local anodyne action on the urinary organs. (e) It does not dilate the pupil so certainly or fully as belladonna. Hyoscyamus is prescribed as an anodyne in irritable conditions of the kidfieys and bladder, and is combined with alkalies, such as the carbonate of potash. The extract of hyoscyamus is often combined with purgatives, to prevent their griping and to assist their action. It has been occasionally prescribed in cases of chorea and epilepsy in dogs. Digitized by Microsoft® 424 VETERINARY THERAPEUTICS Stramonii Folia — Stramonii Semina. The dried leaves and seeds of Datura stramonium, or the thorn apple. The preparations in use are the extract and the tincture. The alkaloid is daturine, which is either identical with hyoscyamine or is a variable mixture of atropine and hyoscyamine. Actions and Uses. — Daturine is almost similar in its actions to atropine. The extract of stramonium is more powerful than the green extract of belladonna, and should be prescribed in half the doses of the latter. Stramonium has a greater depressant effect on the nerves of the bronchi than belladonna. It may be employed in the treatment of spasmodic affections of the respiratory organs, such as asthma and chronic bronchitis. Duboisine. An alkaloid derived from an Australian plant, the Duboisia myoporoides. The sulphate of duboisine is a mydriatic, more power- ful than atropine, and may be employed in solution of 1 grain to the ounce. Stronger solutions may prove toxic. Tabaci Folia — Leaf Tobacco. The dried leaves of Nieotiana tabacum. Tobacco contains from 2 to 8 per cent, of a powerful alkaloid, nicotine. Tobacco smoke contains only the smallest trace of nicotine, or none, but a number of volatile bodies, chiefly pyridine compounds. Actions and Uses. — Tobacco given by the mouth in full doses is a gastro-intestinal irritant. It causes sali- vation, nausea, colicky pains, increased action of the bowels and kidneys, and in dogs vomition. Digitized by Microsoft® TOBACCO— LOBELIA 425 Nicotine is quickly absorbed, and dogs dressed with strong decoctions of tobacco frequently suffer from toxic effects. Nicotine acts chiefly on the nervous structures ; in small doses it causes primary stimulation of the cere- brum and the motor centres of the spinal cord. This is followed by depression, producing intense and universal debility. Full doses cause convulsions and paralysis, respiration is primarily excited, and finally paralyzed, death occur- ring from asphyxia. The heart is first slowed, then accelerated, and finally weakened, due to the effect of the drug on the vagus. Tobacco contracts the pupil and increases most of the secretions, thus differing from belladonna and its allies. Nicotine has been employed in the treatment of tetanus in horses with variable results. It may be administered hypodermically in doses of gr. i. to grs. iii., also in the form of tobacco enemata. Externally, decoctions of tobacco are sometimes em- ployed as antiparasitic applications to cases of mange, lice, fleas, and ticks. Other remedies, however, are far safer, while being just as effectual. Lobelia — Lobelia. The dried flowering herb of Lobelia inflata, imported from North America. Contains an alkaloid, loheline. Preparation. Tinctura Lobeliae — 1 in 8 of proof spirit. Doses. — Horses, §ss. ; dogs, TT\ x. to TT\ xx. Tinctura Lobelise ^therea — 1 in 8 of spirit of ether. Doses. — Similar to the above. Actions and Uses. — Lobelia in medicinal doses is a gastro-intestinal stimulant ; in large doses it is an irri- Digitized by Microsoft® 426 VETERINARY THERAPEUTICS tant. It depresses the respiratory centre and relaxes the bronchial muscles, lowers the activity of the motor centres in the cord, depresses the convolutions secondarily, diminishes the force of the heart and the tension of the vessels, after brief increase of the latter. It kills by paralysis of the respiratory centre, like tobacco. Lobelia, in the form of the ethereal tincture, has been employed in cases of spasmodic asthma, and in small doses makes a useful addition to expectorant mixtures for bronchitis with spasm. Conii Folia— Hemlock Leaves. The fresh leaves and young branches of Conium macu- latum. Conii Fructus — Hemlock Feuit. The fruit of Conium maculatum, dried. Conium contains a liquid alkaloid, conine. Preparations. Hxtractum Conii — a green extract obtained from conii folia, 30 in 1. Doses. — Horses, 3i- to ;^ii. ; dogs, grs. v. to grs. x. Succus Conii — 3 of the expressed juice with 1 of spirit. Doses. — Horses, §i. to §ii. ; dogs, 5SS. to 31. Tinctura Conii — 1 of conii fructus in 8 of proof spirit. Doses. — Horses, f,i. to §ii. ; dogs, ^\ xx. to v\_ xl. Actions and Uses. — Authorities state that conium pro- duces no effect on the sensory nervous system unless indirectly by poisonous doses. The motor nerves are the parts specially acted on ; these are paralyzed from the extremities upwards; the motor regions of the spinal cord are but slightly affected, although reflex excitability is moderately reduced. The respiratory centre in the medulla is paralyzed by a toxic dose, but conium has Digitized by Microsoft® CURARE— CALABAR BEAN 427 no effect on the convolutions of the cerebrum until asphyxia supervenes. Large doses cause weakness of the extremities, drooping and swollen eyelids, dilatation of the pupils, and finally general paralysis. Conium is seldom employed as a therapeutic agent. Conine in the form of the hydrobromate has been pre- scribed in the treatment of tetanus, given hypodermieally in doses of three to five grains, but has not yielded satis- factory results. In spasinodic cough conium is recommended by some authorities, also in the treatment of chorea in dogs. It has no effect on the muscular spasms produced by strychnine. Curara— CuEAEE. An extract from one or more species of Strychnos, owing its activity to an alkaloid, curarina (South American arrow poison). Curare resembles conium in its action, viz., paralysing motor nerves, without removing consciousness. It is said not to exert toxic effects when given by the mouth, but acts as a powerful poison when injected intravenously, hypodermieally, or intratracheally. It has been em- ployed in tetanus, in doses of gr. i. to grs. ii. of the alka- loid, without producing any beneficial results. Physostigmatis Semen — Calabae Bean. The dried seed of Physostigma venenosum. Its activity depends on the presence of two alkaloids, (1) physostigmine 01 eserine ; (2) calabarine. The latter has a stimulant effect on the spinal cord, but otherwise agrees in action with the former. Preparations. Extractum Physostigmatis — Spirituous — 46 in 1. Doses.— Horses, gr. i. to grs. iv. ; dogs, gr. j-V to gr. J. Digitized by Microsoft® 428 VETERINARY THERAPEUTICS Physostigmina — Physostigmine, Bsebbnb. Obtained from the alcoholic extract of Calabar bean. The sulphate and salicylate are the forms generally used. Doses. — Horses and cattle, grs. i. ss. to grs. ii. ; dogs, gr. -Jjj- to gr. J^. Given by hypodermic or intratracheal injection, and combined with pilocarpine in doses of 3 grains for horses and cattle. (1) IMMEDIATE LOCAL ACTION. Physostigmine exerts no topical action on mucous or skin surfaces. It is readily absorbed by the conjunctiva, producing a specific effect of contraction of the ^mjpil. Calabar bean, or physostigmine, administered intern- ally, may cause nausea, and increased peristaltic action, probably of local origin. (2) SPECIFIC ACTION. 'Calabar bean possesses similar actions to its alkaloid physostigmine ; the former, however, contains calabarine, which accounts for the convulsions sometimes noted in experiments with this drug. Physostigmine increases most secretions, such as the salivary, lachrymal, cutaneous, and the secretion from mucous membranes, affecting probably the glandular secreting cells. On the Nervous System. — Physostigmine has no effect on the convolutions of the cerebrum, and consciousness is not lost, though it is impaired by large doses. The spinal cord is the region principally affected by this drug. It causes depression, and finally paralysis of the anterior cornua of the gray matter, which conduct impulses from the brain to the periphery. It acts in a similar manner on the posterior corre«a(sensory portions) of the cord, the result being the production of a complete Digitized by Microsoft® PHYSOSTIGMINE 429 loss of the motor and reflex activity of the cord, and loss of sensibility in the extremities, the extent depending on the amount of the drug administered. The motor and sensory nerves and the muscles are not affected directly, but at a later stage there follows paralysis of the intramuscular termini of the nerves. Occasional muscular twitchings may occur, partly direct in origin. The respiratory centre in the medulla is briefly stimu- lated, and then depressed, being finally paralyzed, death occurring from asphyxia. The cardiac centre is primarily stimulated, as vyell as the intercardiac branches of the vagus, with the result that the heart beats more powerfully and less fre- quently, but finally or after large doses depression occurs. The blood-pressure rises with the increased cardiac action, and then falls later on. On the eye physostigmine causes contraction of the pupil, and spasm of accommodation, whether applied locally or given internally, these effects being due to stimulation of the fibres of the third nerve, thus differing from the contraction caused by opium, which depends on central disturbance. The most important action of physostigmine is exerted on the intestinal canal. Given by hypodermic or intra- tracheal injection, it causes energetic contraction of the involuntary muscular fibres of the intestinal walls, thus producing increased peristaltic action, giving rise to free evacuation of the bowels in a short period of time. It also causes an increase of the fiuids secreted from the intestinal mucous membrane. The large intestines are chiefly acted on by physostig- mine, and the effects produced are more prompt and certain by the addition of pilocarpine. According to Digitized by Microsoft® 430 VETERINARY THERAPEUTICS M. Cagny, physostigmine, veratrine, and pilocarpine all excite the intestinal contractions and secretions, but with the following differences : veratri?ie increases the contractions more than the secretions ; pilocarpine in- creases chiefly the secretions of the anterior portion of the digestive tube, while physostigmine increases the secretions of the posterior portion. Hence he concludes that it is of advantage to combine these three agents in the treatment of intestinal obstruction. M. Kaufmann states that on opening the abdomen of a horse which had received a full dose of physostigmine, energetic contractions of the intestines were observed. Post-mortem examinations of animals poisoned by this drug show pallor, contraction and hardness of the large intestine, the bladder empty and contracted, and the uterus also contracted. We are indebted to Professor F. Smith for reliable information on the action and uses of physostigmine in the horse. This authority prefers the salicylate of phy- sostigmine to the sulphate, as the former produces less colicky pains than the latter. The combination with pilocarpine was found more efficient, a smaller dose being also required. It may be administered by hypodermic or intratracheal injection ; by the latter method it acts quicker. The average medicinal dose, viz., 1^ grains, ad- ministered by hypodermic injection, acts in from twenty to sixty minutes, but may remain an hour and a half before any symptoms are produced. Administered by the trachea, its action may commence in from twenty to twenty-five minutes, but rarely beyond an hour. ' The earliest indications are loud intestinal murmurs, the passage of flatus, with slight colicky pain; this is shortly followed by evacuation of the contents of the Digitized by Microsoft® PHYSOSTIGMINE 431 rectum, and the motions then pass at intervals of a few minutes, each becoming gradually softer, more watery, less formed in balls, until the stage is reached when the evacuations are moist and fluid, resembling cow's faeces. ' All this time the abdominal disturbance has become greater ; the animal lies down, but seldom rolls, the in- testinal murmurs are louder, the passage of flatus almost continuous, straining marked, the faeces voided with great rapidity, often ejected with force, and several ounces of a brown-coloured fluid will at this time accompany each motion. In about two to two and a half hours from the time of injection the effects commence to pass off, and during this time an almost incredible amount of faeces will have been excreted. ' — ' Action of Physostigmine on the Horse,' by Professor P. Smith. See Veterinary Journal, April, 1888. The addition of pilocarpine increases the action of the physostigmine. The symptoms, in addition to those described, are : Salivation of more or less intensity, and increased peristaltic action without increase of abdominal pain. The salivation maybe sometimes excessive, and usually commences in from three to five minutes after injection. The secretion pours from the mouth ; there are constant movements of the tongue, and a large amount of saliva is swallowed. The quantity of saliva swallowed, and also the increased pancreatic secretion, may act both chemi- cally and mechanically on the intestinal canal. Atropine is a physiological antagonist of physostig- mine, as it paralyzes muscles, stimulates the respiratory and cardiac centres, and dilates the pupils. Medicinal Uses. — In impaction of the colon, accom- panied by paralysis of its walls, physostigmine has given excellent results, administered by hypodermic injection. Digitized by Microsoft® 432 VETERINARY THERAPEUTICS Professor F. Smith recommends the intertracheal in- jection of the drug in the form of solution, in 6 to 8 drachms of warm water ; this may be injected into the trachea without inconvenience, the addition of 2 or 3 grains of pilocarpine, as already mentioned, being of advantage. Physostigmine is contra-indicated in cases of volvulus and intussusception, and in inflammatory conditions of the intestine ; hence it is necessary to arrive at a correct diagnosis before prescribing this drug, otherwise a fatal termination may be hastened by increasing inflammatory action or causing rupture of the intestinal walls. Physostigmine should not be employed in the case of pregnant animals, in consequence of its stimulating action on the muscular fibres of the uterus. In tetanus, Calabar bean and physostigmine have been employed, but usually give only temporary relief. In diseases of the eye, physostigmine is applied in the form of solution (2 grains of the sulphate to 1 ounce of water) to ulcerations of the cornea, and, alternated with atropine, to prevent and remove adhesions formed by iritis, physostigmine contracting the pupil, while atropine dilates it. Although antagonistic to strychnine in its action on the spinal cord, physostigmine is of little or no use as an antidote, neither is it of much real service in the treat- ment of poisoning by atropine. Jaborandi — Pilocabpi Foliola. The dried leaflets of Pilocarpus pennatifolius. The most important alkaloid of jaborandi is pilocar- pine. It contains another alkaloid, jaborine, which resembles atropine in its action, and is antagonistic to pilocarpine. Digitized by Microsoft® JABORANDI 433 Preparations. Extractum Jaborandi — Alcoholic and aqueous. Doses. — Horses, 5ss. to 3!. ; dogs, grs. ii. to grs. x. Tinctura Jaborandi — 1 in i of proof spirit. Doses. — Horses, gi. to jii. ; dogs, 3ss. to 51. Pilocarpinae Nitras — Nitrate of Pilocarpine. Doses. — By hypodermic injection ; horses, grs. ii. to grs. iii. ; dogs, gr. ^\ to gr. ^-. (1) IMMEDIATE LOCAL ACTION. Jaborandi applied to the conjunctiva causes contraction of the piopil, by stimulating the terminations of the third nerve. This effect commences quickly, and may last from one and a half to twenty-four hours before finally disappearing. (2) SPECIFIC ACTION. Jaborandi and pilocarpine have the power of stimu- iating glandular secretion. They increase the salivary, lachrymal, nasal, bronchial, intestinal, pancreatic, and urinary secretions. They have little or no effect on the skin of animals, and Professor P. Smith has demonstrated by experiment that the sweat-glands of the horse are perfectly insensible to the action of pilocarpine. Ths secretion of saliva in the horse is greatly increased by the hypodermic injection of 3 grains of pilocarpine ; in five or six minutes free salivation occurs, with champ- ing of the jaws, the effects lasting for over two hours. This action is due to stimulation of the terminal ends of the chorda tympani in the glands, as well as of its centre. The nasal and bronchial secretions are augmented, and in some instances a large amount of bronchial mucus is poured out. Pilocarpine increases intestinal secretion and peristalsis, 28 Digitized by Microsoft® 434 VETERINARY THERAPEUTICS but has less effect on the intestinal muscular fibres than physostigmine, while it stimulates intestinal glandular secretion more powerfully than the latter. In moderate doses it increases the secretion of urine, and is believed to stimulate the 'pancreas. These effects of the drug depend on its power of stimu- lating the peripheral terminations of efferent nerves in glands and involuntary muscles, and also to a stimu- lating effect on the nerve-centres presiding over secretion. The action of the heart is temporarily accelerated, but afterwards slowed and weakened, and blood -pressure is lowered, these effects being partly due to the action of the drug on the vagus in the heart, and partly on the cardiac ganglia. The temperature falls from one half to one degree. The physiological antagonist of pilocarpine is atropine, which arrests glandular secretion and paralyzes the nerve-endings of involuntary muscles. , Medicinal Uses. — The chief use of pilocarpine in veterinary practice depends on its power of increasing intestinal secretion and peristalsis, hence it is combined ■ with physostigmine in the treatment of intestinal impac- tion with paralysis of the intestinal walls (see p. 430). It is recommended by Kaufmann as an expectorant in bronchial catarrh, asthma, etc. It is also recommended in renal affections with a tendency to uraemia; but as it possesses little or no effect on the skin of animals, its therapeutic value in removing urea and water by this channel is doubtful. Pilocarpine has been employed with success as an antidote to atropine. Muscarinae Mitras— Niteate of Muscaeinb. The liquid alkaloid obtained from the fungus Agaricus muscarius, the fly agaric. Digitized by Microsoft® MUSCARINE— GELSEMIUM 435 Actions and Uses. — Muscarine resembles pilocarpine in its actions, but if locally applied to tbe eye it dilates the pupil, while if given hypodermically it causes con- traction of the pupil. It antagonizes atropine in all its actions, with the exception of its effect on the pupil. Muscarine causes contraction of the pulmonary vessels, which effect is overcome by the hypodermic injection of atropine. It is said to cause less salivation than pilocarpine, but to act on the intestines far more powerfully. We are not aware of its employment in veterinary practice. Celsemiuin — Yellow Jasmine. The dried rhizome and rootlets of Gelsemium semper- virens or nitidum. Contains a powerful alkaloid, gelse- mine. Preparations. Tinctura Gelsemii — 1 in 8 of proof spirit. Gelseminae Hydro chloratis — Hydrochlorate of Gelse- mine. Actions and Uses. — Gelsemium acts as a powerful depressant to the motor regions of the spinal cord, pro- ducing paralysis, followed by sensory depression and anaesthesia. Death occurs after toxic doses from asphyxia ; the heart is also depressed. Applied locally it dilates the pupils, but administered internally it causes contraction, resembling muscarine in this respect. Gelsemium has been employed in the treatment of tetanus in the horse, in doses of §ss. of the tincture, or i to 1 grain of the alkaloid, but the effects produced were not anything more satisfactory than those obtained from other drugs. Digitized by Microsoft® 436 VETERINARY THERAPEVTIC8 Ergota— Eegot, Secale Coenutum. The sclerotium (compact mycelium or spawn) of Clavi- ceps purpurea, produced between the pales and replacing the grain of Secale cereale, the common rye. Ergot con- tains an alkaloid, cornutine, and two acids, ergotinic and sphacelinic. Doses. — Horses and cattle, gss. to §i. ; sheep, 3i. to 3i.ss. ; dogs, grs. xx. to grs. xxx. Preparations. Extractum Ergotse Liquidum— 1 in 1 ; aqueous with spirit added. Doses.— Horses and cattle, sii. to 3iv. ; dogs, ni_xv. to ITLxxx. Tinctura Ergotse— 1 in 4 of proof spirit. Doses. — Horses and cattle, §ss. to gi. ; dogs, ni_x. to lll^xxx. Ergotinum — Brgotin. Doses. — Horses and cattle, 3ss. to si. ; dogs, grs. ii. to grs. V. Iiyectio Ergotini Hypodermica — 1 in 2 of camphor- water. Doses. — By hypodermic injection : Horses and cattle, 5SS. to 5ii. ; sheep, Rx. to lT(_xx. ; dogs, lTl_iii. to ]Tlvi. Actions. — The chief portions of the system acted on by ergot are the circulation, the central nervous system, respiration, the intestines and uterus. It stimulates and contracts involuntary muscular fibres, and diminishes the blood stream passing through the arterioles. The arteries become smaller, the hlood-pressure rises, and the heart is reduced in frequency. On the nervous system ergot possesses no direct influ- ence on the highest (cerebral) centres, but may disturb the circulation in the brain. The spinal cord is affected in a marked degree, large Digitized by Microsoft® ERGOT 437 doses producing irritation, followed by paralysis of the sensory centres, evidenced by cramps or twitching of the limbs, staggering gait, and convulsions. Bespiration becomes infrequent after large doses of ergot, and death occurs from asphyxia, due to paralysis of the respiratory centre. The intestines have their peristaltic movements in- creased, and become ansemic. £}ve uterus contracts actively after the administration of ergot, which thus acts as an echolic. It also becomes anemic, these effects being more pronounced if the animal is pregnant, or more so if parturition has com- menced, when the labour pains become more powerful and longer. The effects of ergot on the intestines and uterus are believed to depend on stimulation of the centres in the spinal cord, as well as on an action of the drug on the involuntary muscular tissue. Toxic Effects. — The protracted use of ergotized grain gives rise to a train of symptoms termed ergotism. This is characterized by gastro-intestinal derangement, diarrhoea, impaired circulation and nutrition, resulting in dry gangrene, chiefly involving the extremities — ears and tail. The effect of the drug on the spinal cord may give rise to muscular spasms, and sometimes epileptiform convul- sions. Abortion frequently occurs, especially in cattle, from feeding on ergotized grasses, this being chiefly noticed during wet seasons. Ergot reduces the amount of urine, sweat, and milk, by affecting the local blood-pressure and the gland centres in the brain and spinal cord. Medicinal Uses. — As an echolic, i.e., to cause expulsion Digitized by Microsoft® 438 VETERINARY THERAPEUTICS of the contents of the uterus, ergot is eroployed in the second stage of labour in cases of uterine inertia, where there is no obstacle to the passage of the foetus. Its use demands judgment and care. In fost-partum hcemorrhage ergot is prescribed as a hiBino static, producing beneficial results by causing con- traction of the uterus. It is best given in the form of ergotin, hypodermically. In liamoptysis, hcematemesis, and other internal haemorrhages, ergot is very useful, given by the mouth or hypodermic injection. It is believed to act in such cases by contracting, or even closing, the arterioles, and thus promoting coagula- tion within them. , In retention of the placenta ergot is employed as a constituent of ' cleansing drenches,' the following being a useful formula : ^ Pulv. ergotae, §1. Mag. Bulph, §x. Ammon. carb., ^ss. M. Sig. To be given in two pints of warm ale. Nux Vomica — The Seeds op Stetchnos Nux Vomica. Pulvis Nucis Vomicae — PowDEasD Nux Vomica. Doses. — Horses, grs. xx. to Ji. ; cattle, ^i. to 5ii. ; sheep, grs. x. to grs. xx. ; dogs, gr. i. to grs. iii. Ee- peated twice daily. Preparations. Extractum Nucis Vomicae — Doses. — Horses and cattle, grs. iv. to grs. xv. ; dogs, gr. i to gr. i. Tinctura Nucis Vomicse— contains 1 grain of alkaloids in 1 fluid ounce (1 to 10). Doses.— Horses and cattle, 3ii. to gss. ; sheep, TTl^^xv. to 3i. ; dogs, TTl_v. to TTl_xx. Digitized by Microsoft® STRYCHNINE 439 Nux vomica contains 2 alkaloids, '2 to '5 per cent, of strychnine, and -12 to 1-0 per cent, of brucine united with a crystalline acid, strychnic or igasuric acid. Brucine is much weaker and slower in its action than strychnine. Stry chnina — Steychninb . Prepared by a complex process from nux vomica. Doses. — Horses, gr. | to grs. iii. ; cattle, grs. iii. to grs. V. ; sheep, gr. i to gr. | ; dogs, gr. ^^ to gr. J^.. The minimum doses should be administered at first, and then gradually increased to the maximum amounts. Liquor Stryclininse Hydrochloratis contains 4^ grains to 1 fluid ounce of spirit, water, and dilute hydrochloric acid (1 in 100). Doses. — Hypodermically : Horses, Ji.; cattle, 3i- to 3ii. ; dogs, iTl_ii. to Tl\iv. ACTIONS OF NUX VOMICA AND STEYCHNINE. (1) IMMEDIATE LOCAL ACTION. Externally strychnine possesses powerful antiseptic properties, while brucine is a local anaesthetic. These actions are of no therapeutical value in consequence of the poisonous nature of the drug. Internally nux vomica and strychnine possess all the properties of vegetable bitters, described in Chapter XIII., p. 452. Strychnine is believed to increase the peristaltic action of the intestines. (2) ACTION ON THE BLOOD. Strychnine is rapidly absorbed from all mucous sur- faces, or from the cellular tissues when given by hypo- dermic injection. It enters the blood and reduces the absorptive power of the red corpuscles for oxygen, and lessens the discharge of carbonic acid from the plasma. Digitized by Microsoft® 440 VETERINARY THERAPEUTICS (3) SPECIFIC ACTION. Strychnine enters the tissues quicljly, its effects being especially exerted on the nervous system. It is very slowly excreted therefrom, and if ad- ministered in frequently repeated medicinal doses, it possesses a cumulative action (see p. 43). It exerts a tonic influence on the nervous system, stimulates the gray matter of the spinal cord, increases its reflex excita- bility, and also stimulates other reflex nerve centres. It promotes secretion of saliva, improves appetite, and increases the gastro-intestinal movements. The respiratory, cardiac, and vaso-motor centres are stimulated, causing increased frequency and depth of respirations, and increased number and force of the heart-beats. Some individuals are very susceptible to the action of nux vomica and strychnine. Larger doses or small amounts frequently repeated may lead to sudden twitchings of the muscles of the limbs, hyperaesthesia, and slight difficulty in swallowing. Toxic doses produce violent clonic convulsions, and death from exhaustion and asphyxia, the latter being due to spasmodic arrest of the respiratory muscles. The symptoms resemble those of tetanus to a certain extent, but differ from the latter in the complete relaxa- tion of the muscles between the convulsive seizures, in their sudden development, and in the rapidity of their course, the muscles of the jaws not being primarily affected. The temperature is raised during the convulsions. The convolutions of the cerebrum are unaffected by strychnine. The chief action is exerted on the motor centres of the spinal cord; these are powerfully stimulated, and their reflex excitability greatly increased. Eeflex muscular spasms are originated by the slightest Digitized by Microsoft® STRYCHNINE 441 stimulation' of the skin, or by a loud sound or a bright light. The power of the respiratory muscles is greatly increased, and carried to such an extent that they remain contracted in inspiration, and thus give rise to asphyxia. The vital centres in the medulla are stimulated at the same time, but the muscles and the motor and sensory nerves are comparatively unaffected by strychnine ; its local application, however, is said to stimulate them. Horses and cattle are less susceptible to the action of strychnine than dogs. According to Kaufmann, the toxic dose for the horse is 3 to 6 grains, given hypodermically. Cattle take much larger doses than horses when the drug is ad- ministered by the mouth, while dogs are very suscep- tible, being destroyed by |^ to J of a grain. Antidotes. — In the dog, if noticed early, prompt emetics should be immediately employed. Chloral hydrate forms the most reliable antidote, and in severe cases may be given intravenously. Other antidotes are chloroform (by inhalation), bromide of potassium. Calabar bean, the latter being of doubtful value. Medicinal Uses. — In atonic dyspepsia nux vomica and strychnine are prescribed as hitter tonics. They check unhealthy deviations of the gastric mucous membrane, and thus promote digestion. In convalescence from debilitating diseases, when di- gestion is weak, nux vomica is of great service ; also in cases of recurring flatulence ; it gives tone to the gastric walls, and checks irregular fermentation. In chronic gastric catarrh small doses frequently repeated give bene- ficial results. In all such cases the tincture of nux vomica may be prescribed, along with bicarbonate of soda and gentian or calumba. Digitized by Microsoft® 442 VETERINARY THERAPEUTICS In cases of chronic constipation, depending upon atony of the intestines, nux vomica is prescribed with small doses of aloes to give tone to the intestinal walls and to stimulate peristaltic action. In paralysis, whether of the limbs, intestines, or bladder, nux vomica and strychnine are useful. They are chiefly indicated in chronic motor paralysis, but should not be employed in cases accompanied by irrita- tion or congestion. In cases of weakened motor power succeeding parturient apoplexy in cattle, the hypodermic injection of strychnine gives favourable results. In defective nervous poiver, which sometimes occurs within two or three days after parturition in cows, the use of strychnine is indicated. In cerebro-spinal meningitis in horses, strychnine is recommended by Mr. Lockhart, of New York, in doses of one grain repeated two or three times a day. In canine practice, strychnine is a valuable agent in cases of paralysis resulting from distemper or other causes. It is also employed in convalescence from ex- hausting diseases, in chorea, and in some cases of asthma and chronic bronchitis, and may be combined with iron salts or prescribed in the form of Easton's syrup (see p. 263). In consequence of the cumulative action of nux vomica and strychnine, and the susceptibilities of some patients to the specific action of these drugs, great discrimination is necessary in prescribing them, and the minimum doses should be employed at first. In cases of paralysis the doses should be gradually increased, and in some instances it may be necessary to continue them until slight muscular twitchings are produced. Digitized by Microsoft® CAFFEINE 443 Caffeina — Caffeine. An alkaloid usually obtained from the dried leaves of Camellia thea (the tea plant) or the dried seeds of Coffea Arabica (the coffee plant). Caffeine and theine are con- sidered identical, and the same alkaloid is also obtained from the leaves of gurana, as well as from kola seeds. It is homologous with theobromine, which is obtained from the Theobroma cacao. Doses. — Horses and cattle, grs. xv. to 3i. ; dogs, gr. i. to grs. iv. Caffeinae Citras — Citbate of Caffeine. A weak compound of caffeine and citric acid, and may be administered in double the doses of the above. Actions and Uses. — Caffeine stimulates, and subsequently paralyzes, the nerve centres of the cerebrum, but in the lower animals the spinal centres are simultaneously affected to such a degree that convulsions occur, resem- bling those produced by strychnine. It exerts a restora- tive effect in both voluntary and involuntary muscles, and muscular contraction seems more easily executed. Caffeine primarily stimulates the cardiac and respiratory centres in the medulla ; it strengthens and lengthens the cardiac systole, while diastole is shortened ; large doses cause death by arresting the heart in systole. The blood- pressure first rises and then falls, and temperature is temporarily raised. Caffeine is excreted in the urine and bile, and in passing through the kidneys the renal cells are stimu- lated. This, in conjunction with its effects on the heart and vessels, causes it to act as a diuretic. Caffeine has been employed in cases of cardiac diseases with dropsy in canine practice, being more rapid and less irritant than digitalis. It has also been prescribed as a nerve stimulant in cases of milk-fever in cows and in distemper in dogs, but with doubtful results. Digitized by Microsoft® 444 VETERINARY THERAPEUTICS CHAPTEE XII. THE VEGETABLE 'KmQT)OU— Continued. Digitalis Folia — Foxglove Leaves. The leaves of Digitalis purpurea, the purple foxglove, carefully dried. The active principle of digitalis is known as digitalinum or digitalin. This is proved to be a compound of four glucosides, namely : (1) Digitalin proper; (2) digitalein; (3) digitoxin; (4) digitonin. Digitalin is seldom prescribed ; the dose for the horse is stated to be from gr. ^ to gr. i. Licompatibles of Digitalis and its Preparations. — Per- salts of iron, which give a slight inky colour, by com- bining with the tannic acid present in the drug ; acetate of lead ; preparations of cinchona. Preparations. Pulvis Digitalis Folia— Powdered Digitalis. Doses. — Horses, grs. xv. to 5ss. ; cattle, 5s8. to ^i. ; sheep and pigs, grs. v. to grs. x. ; dogs, grs. ss. to grs. ii. Eepeated twice daily, with due precautions in con- sequence of the cumulative action of the drug. Tinctura Digitalis — 1 in 8 of proof spirit ; contains 54J grains to the fluid ounce. Doses. — Horses, 3i.ss. to 3iv. ; cattle, 3iv. to 5v. ; sheep, n\ XX. to TTl_xxx. ; dogs, Tf[ v. to (T^xx. ACTIONS OF DIGITALIS. (1) IMMEDIATE LOCAL ACTION. Externally digitalis exerts a slightly irritant action, but is not absorbed by the unbroken skin according to some authorities ; others state that it can be absorbed when applied as a decoction to the skin. Digitized by Microsoft® DIGITALIS 445 Internally, in full doses, it deranges digestion in all animals, causing nausea, and occasionally diarrhoea with, vomiting in dogs. ' These effects are due to both a local and a specific action. (2) ACTION ON THE BLOOD AND SPECIFIC ACTION. The active principles of digitalis enter the blood freely, and reach the tissues ; they are slowly eliminated there- from, so that even small doses, if too frequently repeated, tend to accumulate in the system. Digitalis, when administered through the circulation, or applied for the purpose of experiment to the exposed heart, induces persistent contraction of the ventricles. It also causes an increase of vigour and diminution of frequency of the cardiac action, with contraction of peri- pheral vessels and rise of blood-pressure. The chief specific action of the drug is exerted on the circulatory organs, the other portions of the system being affected in a secondary manner. The action of digitalis on the heart and bloodvessels is divided by Dr. Mitchell Bruce (' Materia Medica and Therapeutics ') into four stages, as follow, the first being shorter, and the other stages more marked, as the dose is increased. First Stage. — The heart falls in frequency, and heats with increased force, these effects being due respectively to stimulation of the vagus in the heart and medulla, and to stimulation of the intrinsic cardiac ganglia. The arterial pressure rises, due to the increased cardiac force, and to stimulation of the vaso-motor centre and vaso-motor nerves. The total result of these effects is that the diastole is lengthened and the ventricles are well filled, while, in consequence of increased cardiac farce, the ventricles are Digitized by Microsoft® 446 VETERINARY THERAPEUTICS thoroughly emptied, and the arteries are well filled, and are kept in this condition by the vaso-motor action of the drug. Thus, the veins are more thoroughly emptied, and the arteries Tproimrly filled. Second Stage. — The vaso-motor apparatus of the renal aj'teries is suddenly depressed and these vessels become relaxed, while the state of the heart remains unchanged. There is thus increased force of circulation on the renal glomeruli, the result being an increase in the excretion of the urinary luater, digitalis thus being a diuretic. Third Stage. — The heart rises in freguency, due to depression of the vagus, and probably also to irritation of the accelerator nerves ; it loses force as the intrinsic ganglia and heart - muscle commence to become ex- hausted. The vaso-motor apparatus becomes depressed, and this, along with the weakening of the heart, causes the arterial pressure to fall throughout the system. The total result is commencing failure of the circula- tion. Fourth Stage. — The intrinsic ganglia and the myo- cardium fail, the action of the heart becomes irregular, infrequent, and weak, being finally arrested in diastole, the blood pressure gradually sinking from loss of cardiac power and paralysis of the vessel walls. Death is due to general circulatory failure. Bespiration is temporarily quickened, but more per- manently slowed, and fails at last only through the circulation. The temperature is temporarily raised by the increased circulatory force, but is lowered by the augmented blood- flow in the skin. The central nervous system is not directly acted on by digitalis, but is secondarily affected through the blood- supply ; it has no marked' effect on sensory or motor nerves. Digitized by Microsoft® DIGITALIS 447 On the kidneys the effect of digitalis is uncertain in the healthy animal, as it depends on the period at which the renal vessels commence to relax, on the duration of the second stage, and on the relation of the action of the drug on the heart to its action on the vessels, these all being variable. Authorities state that in a healthy animal the urine is not increased in bulk, but that in cases of disease, such as certain forms of dropsy, it is increased in a marked degree. The action of the drug on the urine is not due to any direct influence on the renal cells, but chiefly on the heart and vessels generally, partly on the renal arteries. Toxic Effects. — According to Her twig, 1 ounce, and in some cases 6 drachms, of powdered digitalis, administered in bolus to horses, caused in three to ten hours loss of appetite, frequent urination, fluid faeces sometimes tinged with blood, the pulse at first full and frequent, but after- wards small, slow, and irregular, diflBculty of respiration, contraction of the pupil, languor, and death after twelve to sixteen hours. Messrs. Bouley and Eeynal, experimenting with large doses of digitalis in horses, found that the circulation became more rapid, the heart-beats more abrupt, and their energy increased, and accompanied after a certain time with a vibratory thrill and a decided metallic tinkling. As poisoning went on, a distinct bellows murmur was heard, becoming more audible on exertion ; the pulse was small, thready, and intermittent ; and as death approached the beats were very rapid, being from 90 to 140 per minute (Dr. Einger, ' Hand-book of Therapeutics ') . Medicinal Uses. — In affections of the heart, digitalis, employed judiciously, is an agent of great therapeutical value. Digitized by Microsoft® 448 VETERINARY THERAPEUTICS It is indicated when the nervo-muscular structures of the cardiac walls tend to fail, resulting in a fall of the cir- culatory force, the cavities of the heart being incompletely emptied, the arteries insufficiently filled, and the veins im- perfectly drained. In such cases the pulse becomes small, V7eak, and irregular ; cardiac distress occurs, the veins become distended, dropsy and visceral disorder super- vene, and frequently congestion of the lungs with marked dyspnoea is present. This condition occurs under a variety of circumstances, such as the different forms of valvular disease. In the case of horses affected with marked organic disease of the heart treatment is useless for obvious reasons ; however, in favourite animals, and in dogs, it may be required in order to prolong life at the request of the owners. Digitalis is hidicated when natural compensation fails or does not occur (see p. 135) ; it produces beneficial results by lengthening diastole, and thus increasing the force of the cardiac wall, by this means prolonging venous flow and ventricular rest ; the pressure in the arteries is sustained, and the blood driven in a steady stream into the veins. The symptoms noted above will thus be alleviated and the dropsy removed, absorption of the fluid being accom- plished by increased venous flow, the profuse diuresis causing its excretion by the kidneys. In such cases attention must be paid to digestion and to dietetics, and it is often of advantage to combine digitalis with a preparation of iron and quinine. In pericarditis, digitalis is recommended in the earlier stages by some practitioners, but Professor Williams is of opinion that in this affection the drug acts injuriously, interfering with the appetite, and tending to accumulate in the system. Digitized by Microsoft® DIGITALIS 449 In functional or nervous palpitation, accompanied with debility, or in reflex cases with gastric disorder, small doses of digitalis, by controlling the vagus, give favour- able results in many instances ; but it is necessary to remember the tendency of the drug to interfere with digestion. During convalescence from influenza, or other exhausting diseases, we sometimes find an irregular or an intermittent pulse, which is greatly benefited by the judicious administration of digitalis, combined with mineral and vegetable tonics. In broken wind and chronic cough digitalis is frequently employed in combination with other drugs, and is cer- tainly of value in many cases, although we may not be able to explain its action on these affections in a satis- factory manner. The late Professor Dick recommended in such cases a combination of 30 grains each of digitalis, opium, camphor, and calomel, given once daily ; while if continued for a week or longer, the calomel should be omitted. In suppression of serine, accompanying nephritis, where it becomes necessary to excite the secretion, Professor Williams recommends a decoction of digitalis, repeatedly applied as a fomentation to the loins, or as a poultice ; this is to be discontinued immediately after the kidneys have commenced to act. Contra-Indications. — In pure hypertrophy of the heart, and during the compensation period, digitalis should not be employed (see p. 135). In aortic incompetence it is contra-indicated, as it pro- longs diastole, and thus permits a greater reflux of blood but if the ventricle tends to fail it may be employed. In fatty degeneration of the heart digitalis should be withheld, as by causing irregular contraction it may lead to rupture. 29 Digitized by Microsoft® 450 VETERINARY THERAPEUTICS In irritable or dyspeptic conditions of the alimentary canal, digitalis should not be prescribed until a normal state of digestion is brought about. In prescribing digitalis it is necessary to remember the cumulative action of the drug, so that proper intervals be allowed between each dose, otherwise it enters the tissues more quickly than it is excreted, and may suddenly exert toxic effects. Convallaria. The entire plant of Convallaria majalis, the lily of the valley. Pre2Mrations. Extractum Convallarise — Aqueous. Doses. — Horses, Jss. to 3ii. ; ^ogs, grs. ii. to grs. viii. Tinctura Convallarise — Doses. — Same as those of tincture of digitalis. Actions and Uses. — Convallaria resembles digitalis in its actions ; it has also decided diuretic effects. It has been employed with success in some cases of cardiac dropsy, and is recommended in cases of func- tional and organic cardiac affections. It is said to be less liable to cause nausea than digitalis, but is seldom used in veterinary practice. Strophanthus. The mature ripe seeds of Strophanthus hispidus. Preparation. Tinctura Strophanthi — 1, dried, in 20 of pure ether and spirit. Doses. — Horses, Ji. to 3ii. ; dogs, n\_ii. to Tl\ x. Digitized by Microsoft® SQUILL 451 Actions and Uses. — Strophanthus is a cardiac stimulant and diuretic, being closely allied to digitalis in its action on the circulation, and may be prescribed in the same class of cases where digitalis has failed or disagreed. Scilla— Squill. The bulb of Urginea scilla. Preparations. Acetum Scillse — 1 in 8 of diluted acetic acid. Syrupus Scillse — Acetum scillse 1 with 2 of refined sugar. Doses. — Horses, |i. ; dogs, Jss. to 5i. Actions and Uses. — Squill closely resembles digitalis in its action on the heart and circulation, and produces diuresis in a similar manner. Two points of difference require notice : (1) Squill is more irritant to the stomach and intestines than digitalis, causing vomiting and purging when ad- ministered in full doses to dogs. (2) Squill is a powerful expectorant, this action being probably a remote local one, the active principle of the drug stimulating the structures in the bronchial walls during its excretion. It may be prescribed as a stimulant expectorant in cases of chronic bronchitis, in which it produces beneficial results by increasing the local circulation and secretion, accelerating the removal of the products, and strengthen- ing the action of the heart. It may be combined with the liquor ammonii acetatis or with camphor. Digitized by Microsoft® 452 VETERINARY THERAPEUTICS CHAPTEE XIII. THE VEGETABLE KmGDOM.— Continued. Simple Bitters, Aromatic Bitters, and Aromatic Volatile Oils. These form a large group of vegetable substances, and it will be convenient to select a type of each class for a full description of its actions and uses, and to compare the others with it. As a type of simple bitters we may select calumba, and as types of aroviatic hitters we have gentian and auran- tium. Certain alkaloids, such as quinine, strychnine, etc., also possess actions as bitters. Aromatic volatile oils are represented by oil of cloves, oil of peppermint, etc. Calumbae Radix — Calumba Eoot. The dried transversely cut slices of the root of Jateor- rhiza calumba. Active principle : calmnbin. Preparations. Calumbse Radix Pulvis — Powdered Calumba. Doses. — Horses, 5ii. to 3iv. ; cattle, gi. to |ii. ; sheep and pigs, 3ss. to 3i. ; dogs, grs. v. to grs. xx. Tinctura Calumbae — 1 in 8 of proof spirit. Doses. — Horses, §i. to ^ii. ; cattle, §ii. to §iii. ; sheep and pigs, 3i- to 5ii. ; dogs, 3ss. to 3i. ACTIONS OF CALUMBA AND OTHEE VEGETABLE BITTBES. (1) IMMEDIATE LOCAL ACTION. Externally. — Calumba and other bitters possess anti- septic and disinfectant properties, and to a certain extent Digitized by Microsoft® CALVMBA, AND OTHER VEGETABLE BITTERS 453 are capable of arresting decomposition and fermentation, but they are not employed for this purpose. Internally. — In the mouth calumba and other bitters stimulate the 'nerves of taste, and also induce several reflex effects of importance in connection with digestion, as follows : (a) They increase the flow of saliva, and thus favour the necessary action of this secretion on the food in the mouth, as well as its stimulant action on the gastric secretion. (6) They stimulate the vessels and glands of the stomach through the central nervous system, and thus increase gastric secretion in a second way. This effect is heightened if. the bitter be aromatic, and there is in- creased relish given for food by the pleasant flavour. (c) In the stomach calumba and other bitters act directly on the gastric nerves, causing a sensation closely resembling hunger. The appetite is thus increased, and if food be given shortly afterwards the effects described above afford means of ensuring proper digestion of it. The action of bitters is assisted by a combination with aromatics, and with alcohol (such as contained in tinctures of the drugs). {d) Calumba and other bitters exert a controlling action on any decomposition or excessive fermentation which may be set up in the stomach and intestines. They pass slowly along the intestines, and unless they contain tannin (which is present in many), they slightly increase peristaltic action. If given in excess, or for too long a period, bitters tend to irritate the stomach and induce indigestion. (e) Bitters, besides increasing the local circulation, also produce a remote effect on the heart and systemic vessels, causing increased blood-pressure, and acting as ' general tonics.' Digitized by Microsoft® 454 VETERINARY THERAPEUTICS (2) ACTION ON THE BLOOD, AND SPECIFIC ACTION. We are not aware of any direct action of bitters on the blood or tissues beyond those just described. Their in- direct action is decided, as they are the means of intro- ducing into the blood an increased amount of nutrient material, thus acting as tonics. Medicinal Uses. — As stomachics calumba and other bitters are of great value, and are frequently employed to stimulate gastric digestion in cases of atonic dyspepsia, where the appetite and powers of digestion and assimila- tion are interfered with, such as occur in convalescence from acute diseases, also in overworked animals, and in instances due to errors of dieting. They are combined with acids or with alkaline stomachics, as the case may require, and are rendered more active by the addition of an aromatic tincture. Calumba is one of the least irritating of the bitter stomachics. Bitters should not be continued for too long a period, or administered in too concentrated a form. In cases of dyspepsia accompanied by pain, and excessive mucous secretion, or, in the case of dogs, by vomiting, and in organic disease of the stomach, they must be prescribed with caution or avoided altogether. The action of bitters on the intestines increases their value in cases of indigestion, as they remove flatulence and tend to promote evacuation. Given by the mouth, or in the form of enema, in- fusions of bitters act as anthelmintics, preventing and destroying threadworms. Quassias Lignum— Quassia Wood. The chips, shavings, or raspings of the wood of Picraena excelsa. Active principle : quassin. Digitized by Microsoft® QUASSIA-GENTIAN 455 Preparations. Infusum Quassias — 1 in 80 of cold water. Doses. — Horses and cattle, ^iv. to gviii. ; dogs, Ji. to 5iv, Tinctura Quassiae — 1 in 27 of proof spirit. Doses. — Horses and cattle, §ss. to §i.ss. ; dogs, 3ss. to^i Actions and Uses. — Quassia is a simple bitter, possess- ing the various properties fully described under calumba. The following points are worthy of notice : (1) Its preparations contain no tannin, and may be combined with salts of iron without any chemical change occurring. (2) It is intensely bitter, as compared with calumba or gentian. (3) The infusion of quassia, used as an enema, is an excellent anthelmintic remedy destroying both ascarides and lumbrici. Centianae Radix — Gentian Eoot. The dried root of Gentiana lutea, the yellow gentian. Contains 1 per cent, of a bitter glucoside, gentiopicrin. Preparations. Pulvis Gentianae Radix — Powdered Gentian. Doses. — Horses, |ss. to ji. ; cattle, ^i. to gii. ; sheep and pigs, 3i. to 3ii. ; dogs, grs. v. to grs. xx. Eepeated two or three times daily. Tinctura G-entianae Composita — Compound Tincture of Gentian — Gentian, 6 ; bitter orange-peel, 3 ; cardamoms, 1 ; proof spirit, 80. Doses. — Horses, f,\. to §ii. ; dogs, 5ss. to 3ii. Actions and Uses. — Gentian possesses the action of other bitters as described under calumba. It is most extensively employed in veterinary practice, is slightly Digitized by Microsoft® 456 VETERINARY THERAPEUTICS aromatic, possesses but little astringency, and is more stimulant to the bowels, and more disinfectant than many other bitters. In cases of atonic dyspepsia, especially among young animals, it is useful, conjoined with bicarbonate of soda and ginger. As a general tonic it may be combined with sulphate of iron. In convalescence from debilitating diseases gentian is an excellent stomachic, and in combination with alcohol, such as in the form of tincture, or administered in ale, it proves a valuable stimulating tonic. In cattle practice it is also largely employed, in cases of indigestion, torpidity of the rumen, etc., and may be combined with nux vomica, and small doses of sulphate of magnesia. In canine practice, the compound tincture of gentian forms one of the best vegetable tonics, and may be com- bined with quinine with advantage. Aromatic bitters resembling gentian are cascarilla, chirata, serpentaria, canella, cusparia, etc. Aurantii Fructus — Bitter Oeangb. Preparation. Tinctura Aurantii — 6 of fresh rind in 20 of spirit. This substance is an aromatic and hitter, and is chiefly employed as a flavouring agent in pharmacy. Hydrastis Rhizoma. The dried rhizome and rootlets of Hydrastis cana- densis, or yellow root. Pre'pajxttioji. Extractum Hydrastis Liquidum — spirituous and aqueous — 1 in 1. Actions and Uses. — Hydrastis is a hitter and a spinal stimulant, somewhat resembling nux vomica. Applied Digitized by Microsoft® OIL OF CLOVES 457 to mucous surfaces it acts as a kamostatic and astringent. Its chief use in veterinary practice is in the treatment of nasal gleet, depending on a diseased condition of the Schneiderian mucous membrane. It is used in the form • of an injection by means of a syringe, and of the strength of one ounce to one quart of warm water. The liquid extract of the United States Pharmacopoeia is said to be the best preparation of the drug for this purpose. Oleum Caryophylli — Oil op Cloves. The oil distilled from the dried flower-buds of Eugenia caryophyllata, or clove. Cloves may be taken as a type of a large group of agents known as the aromatic volatile oils. These are of complex and variable chemical composition, and are closely allied, on the one hand, to phenol and benzoic acid, and on the other hand to the balsams and gum- resins. We shall describe the actions of oil of olives at length, so that it will only be necessary to compare the other members of the group with it. (1) IMMEDIATE LOCAL ACTION. Oil of cloves and allied substances closely resemble oil of turpentine in their properties. Applied to the skin they cause redness, and a degree of inflammation, with temporary pain, which gives place to local anaesthesia. They act as antiseptics, local ancesthetics, stimulants, and cotmter-irritants, turpentine and camphor being common applications for these purposes. Internally. — In the mouth oil of cloves and its allies act as antiseptics, they also cause dilatation of the local vessels, and thus increase circulation, heat, and nutri- tion ; in concentrated form they may even cause in- flammation. Simultaneously the nerves of taste are Digitized by Microsoft® 458 VETERINARY THERAPEUTICS powerfully excited, and certain reflex results of import- ance in digestion follow these local changes. (a) There is increased flow of saliva and of mucus. (b) The gastric mucosa becomes hyperaBmic, causing a sense of hunger, and a flow of gastric juice. (c) The appetite is stimulated, and there is increased relish for food. In the stomach the aromatic volatile oils act as power- ful stomachics, as follows : The gastric vessels are dilated, the gastric nerves are first stimulated and then soothed, pain is thus relieved, and the contents of the stomach, if tending to decompose, as in dyspepsia, are partly disin- fected. There are important reflex effects. The muscular coat of the stomach is stimulated, and the gastric move- ments increased, with probable relaxation of the cardiac orifice in the case of dogs. Flatulence and spasm are relieved, the aromatic volatile oils thus acting as carminatives. By reflex action also distant organs are stimulated. The action of the heart is increased, the blood-pressure raised, and the spinal and medullary centres are temporarily excited. These agents thus act as general stimulants and anti- spasmodics. In tlie intestines portions of the aromatic oils remain unabsorbed, and increase the local circulation and secre- tions, also stimulating the peristaltic movements and expelling flatus. They relieve or prevent pain and spasm, and are often employed as correctives of the griping tendencies of many purgatives. Oil of cloves possesses a slight astringent action by reason of the tannic acid it contains. (2) ACTION ON THE BLOOD. Oil of cloves and other aromatic oils enter the blood, and are partly oxidized by the red corpuscles ; they then Digitized by Microsoft® OIL OF CLOVES— OIL OF PEPPERMINT 459 leave the circulation mainly unchanged. Some are be- lieved to increase the number of white corpuscles by dilating the abdominal vessels, and thus stimulating the organs which supply the blood with leucocytes. (2>) SPECIFIC ACTION. Unless given in very large doses, the aromatic oils do not produce any specific effects on the tissues or organs. Generally speaking, they are stimulants and anti- spasniodics, but the major part of this effect depends on reflex action from the stomach, such as described previously. (4) EEMOTE LOCAL ACTION. The aromatic oils are excreted by the kidneys, skin, bronchi, liver, and intestines, partly unchanged and partly as resins. In passing through these structures they stimulate, and to a certain extent disinfect, them, this being especially the case with the oil of turpentine. Medicinal Uses. — These will be discussed under the heading of each member of the group. Oil of cloves has been recommended as an application to cases of open joint, the beneficial effects recorded being probably due to its anodyne and disinfectant properties. Oleum Menthae Piperitae— Oil op Peppermint. The oil distilled from fresh flowering peppermint, Mentha piperita. Composition. — It consists of a terpene, menthene, and stearoptene, menthol, or peppermint camphor. Actions and Uses. — Oil of peppermint resembles other aromatic oils in its actions. It differs, however, in its action locally, as, instead of dilatation, it causes at first active contraction of the vessels, leading to a sensation Digitized by Microsoft® 460 VETERINARY THERAPEUTICS of coldness when taken by human beings. It paralyzes the ends of sensory nerves with which it is brought in contact, and hence relieves gastro-intestinal pain, and acts as a carminative. It is contained in the tinctura chloroformi et morphinse (see p. 338). Menthol is a vascular stimulant and local anmsthetic. Thymol. — A stearoptene obtained from the volatile oils of Thymus Vulgaris. It is antiseptic, disinfectant, and deodorant. A saturated solution in water is a very powerful antiseptic, but seldom employed. In the form of spirituous solutions in ointments it has been used as an application in skin affections. Oil of Origanum is obtained from Thymus vulgaris ; it acts as an irritant when rubbed into the skin, and is often added to blistering ointments and liniments. Oil of Lavender and Oil of Rosemary resemble the other aromatic oils in their action, and are chiefly employed as components of stimulating liniments. Compound tinc- ture of lavender is contained in liquor arsenicalis, and the oil of lavender is an ingredient of compound cam- phor liniment. Zingiber — Gingee. The scraped and dried rhizome of Zingiber of&cinale. Ginger contains an aromatic volatile oil, a complex mixture of hydrocarbons and their oxidation products. Doses. — Horses, 3iv. to gi. ; cattle, §i. to §ii. ; sheep and pigs, 5!. to 3ii. ; dogs, grs. x. to grs. xx. Pf-eparation. Tinctura Zingiberis — 1 in 8 of spirit. Doses. — Horses, §ss. to gi. ss. ; dogs, Tll_xv. to in_xx. Actions and Uses.^Ginger is extensively employed as a carminative and stomachic in all patients. It is com- bined with purgatives to diminish their tendency to Digitized by Microsoft® ANISE— ARNICA 461 nauseate and gripe, being added to the aloetio bolus for the horse, and to the sulphate of magnesia for rumin- ants. Anisi Fructus — Anise Feuit. The dried fruit of Pimpinella anisum. The chief con- stituent is the of&cial oil. Oleum Anisi — Oil op Anise. The oil distilled from anise fruit. Actions and Uses. — ^The actions and uses of anise re- semble those of the aromatic oils in general. It is believed to possess a stimulant action on the bronchial mucous membrane, being excreted partly by this channel, hence it is a favourite component of formulae for the relief of cough in horses, besides being a flavouring agent. The anise fruit may be given to horses in doses of Jss. to gi. in combination with other remedies. The oil of anise is seldom employed except as a flavouring ingredient. Caraway, Coriander, Fenugreek, Fennel, Dill, Carda- moms, all contain aromatic volatile oils, and resemble anise in their actions. They enter into the composition of various ' condition powders ' and popular condiments for horses and cattle. Arnicae Rliizoma. The dried rhizome and rootlets of Arnica montana. Arnica contains a small quantity of volatile oil of complex composition, also tannic acid and a resinous glucoside, arnicin. Preparation. Tinctura Arnicae — Tincture of Arnica — 1 in 20. Doses. — Horses, §i. to §ii. ; dogs, 3ss. to 5i. (1) IMMEDIATE LOCAL- ACTION. Externally. — Arnica applied to the skin increases the cutaneous circulation. Digitized by Microsoft® 462 VETERINARY THERAPEUTICS Internally it is a stimulant to the alimentary canal, like volatile oils in general. It also acts as a general stimulant when given in medicinal doses, probably in part by a reflex action from the stomach. (2) SPECIFIC ACTION. It acts as a stimulant to the brain and whole nervous system. In large doses it is an irritant to the gastro- intestinal canal, and causes depression of the circulation and nerve centres. It is excreted by the kidneys and skin, exerting remote stimulant effects thereon. Medicinal Uses. — Internally the tincture of arnica is recommended by Professor Williams in cases of pul- monary congestion, and he advises the administration of one or two ounces, believing that it stimulates the cuta- neous circulation, and is calculated to restore the equili- brium of the circulation in the system. Externally arnica is extensively employed as an ap- plication to strains and bruises, etc., and although some authorities question its therapeutic value in such cases, experience enables us to state that it produces beneficial effects. It prevents swelling, and hastens the absorption of effused blood, and according to Dr. Phillips (' Materia Medica and Therapeutics') it has the power of restoring contused muscular fibre to its healthy condition in a short space of time. He recommends the internal administration of small doses of arnica every two or three hours in cases of con- cussion and shock, also in haemorrhages arising from mechanical violence, such as epistaxis and haemoptysis. Arnica may be employed in the form of liniments, con- taining from two to four ounces of the tincture to the pint of water, combined with tincture of camphor or soap liniment (see p. 230). Digitized by Microsoft®' TURPENTINE 463 Oleum Terebinthinse — Oil of Tuepentine. The oil distilled from the oleo-resin (turpentine) ob- tained from Pinus Australis, Pinus teeda, and some- times from Pinus pinaster and Pinus sylvestris, rectified if necessary. The oleo-resin, turpentine, is an impure solution of resin in 15 to 30 per cent, of the official volatile oil. Doses. — Horses, §i. to §ii. ; cattle, §ii. to Jiii. ; sheep and pigs, 3i. to 3iv. ; dogs, ^\x. to n^xxx. ; sis-month-old calves, §ss. ; six-month-old lambs, 3i- The oil of turpentine should be well shaken up in bland oils, or made into an emulsion with mucilage or eggs, before administration, so as to avoid its irritating effects on the mouth and throat. Preparations. Linimentum Terebinthinse — 01. tereb., 16; camphor, 1 ; soft soap, 2 ; water, 2. Mix the soap with the water ; dissolve the camphor in the turpentine ; rub all together till mixed, and add sufficient water to make a fluid emulsion. ACTIONS OF TUEPENTINE. (1) IMMEDIATE LOCAL ACTION. Externally. — Turpentine, applied to the skin or ex- posed mucous membranes, acts as an antiseptic and dis- infectant, and also as a local stimulant and counter-irritant. It stimulates the local circulation, acts as a rubefacient, and if applied of sufficient strength, acts as a vesicant. It irritates the local nerves at first, and then depresses them. Some animals are very susceptible to this local effect of oil of turpentine, which causes a high degree of irritation, especially in horses and dogs with thin skins. Turpentine may be absorbed by the unbroken skin. Digitized by Microsoft® 464 VETERINARY THERAPEUTICS Internally. — In the stomach oil of turpentine in medi- cinal doses acts as a loowerful carminative, resembling other aromatic volatile oils in this respect. It is a gastric disinfectant a stimulant to the vessels, a sedative to the local nerves, and a temporary reflex stimulant. In the intestines turpentine exerts important actions, and may be found in the colon, in which also it is partly excreted. It acts in a reflex manner as a stimulant to the muscular coat of the intestines, causing contraction, expulsion of gas and faeces, and recovery of tone (if this has been lost by tympanitic distension) ; it also acts as a disinfectant and vascular stimulant, while in large doses purgation will be produced. Turpentine acts also as an anthelmintic, being capable of destroying intestinal parasites. Used in the form of an inhalation, the oil of turpentine acts as a stimulant and disinfectant to the respiratory organs. (2) ACTION ON THE BLOOD. Oil of turpentine is freely absorbed from all surfaces, and enters the blood unchanged. Even in medicinal doses it is believed to be partially oxidized at the ex- pense of the blood. If injected intravenously, it may produce rapidly fatal effects, which are partly referable to its coagulating influence on the blood. (3) SPECIFIC ACTION. In medicinal doses oil of turpentine acts as a reflex stimulant as well as a general stimulant. It is rapidly absorbed, diffused, and excreted. In full doses it causes at first stimulation and then paralysis of the vaso-motor centres ; the blood-pressure falls, and the action of the heart is disturbed. The cere- bral and spinal centres are briefly stimulated, and then Digitized by Microsoft® TURPENTINE 465 depressed, the actions of the drug in toxic doses resem- bhng those of alcohol (see p. 325). Experiments demon- strate that large doses given to dogs cause gastro-enteritis, staggering gait, irritation and congestion of the urinary organs, and frequently hsematuria. The antidotes recommended are small doses of sulphate of magnesia, demulcent drinks, and laudanum or mor- phine to relieve pain. (4) EEMOTE LOCAL ACTION. Oil of turpentine, like the majority of volatile oils, is excreted almost unchanged by the cutaneous and mam- mary glands, by the lungs and respiratory passages, the kidneys, and probably by the liver and intestines. During its excretion by these channels it produces important effects. In moderate doses it causes diuresis, while excessive amounts may produce complete suppression of urine, "irri- tation and congestion of the urinary organs, repeated attempts at micturition, and frequently hasmaturia. Part of the drug is excreted as a violet smelling body ; this and the unchanged portion exert remote local effects as stimulants and disinfectants in the bladder and urethra. During its excretion by the respiratory passages oil of turpentine acts as a vascular stimulant to the bronchial walls, and as a disinfectant to the parts and to their pro- ducts. Its excretion by the colon contributes to its effect in causing the expulsion of gas and faeces. Medicinal Uses. — In gastric tympany and flatulent colic in horses, the oil of turpentine is a very valuable remedy, causing expulsion of the gas, arresting fermentation, and giving tone to the muscular coat of the organs involved. It may be administered along with a purgative dose of ol. lini, and combined with the spiritus ammon. aromat., 30 Digitized by Microsoft® 466 VETERINARY THERAPEUTICS while if pain be present, ehlorodyne or tr. opii may be given in addition. In tympanitis of the rumen, commonly known as hoven in cattle, oil of turpentine is also a very effectual agent, and may be given in full doses, combined with a prepara- tion of ammonia and an oleaginous purgative. In cases of indigestion, characterized by distension of the rumen and general digestive disturbance, frequently met with in calves, oil of turpentine, combined with spi- ritus ammon. aromat. and ol. lini, gives excellent results, prescribed in the following formula : ^. 01, tereb., §ss. ; spiritus ammon. aromat., 5i-ss. ; ol. lini, O.ss. P. m. This may be repeated in three hours if necessarj'. In purpura haynorrhagica, oil of turpentine is an agent of great value, probably producing its effects by some special action on the bloodvessels. It may be administered in ounce doses, combined with a preparation of iron, twice or three times daily, and mixed in a proper amount of milk and eggs, chlorate of potash being given at the same time in the patient's food or drinking-water. As a hceiTiostatic, oil of turpentine is of unquestionable value in cases of internal hemorrhages, such as from the lungs, stomach, intestines, and uterus. In such instances it may be given in large doses, care being taken that it is properly diluted with some bland fluid. As an anthelmintic, oil of turpentine is an effectual agent for horses, but should be avoided in dogs, as it is likely to produce irritating effects. For the horse, in the case of tapeworms, the following is a useful formula ; R. 01. tereb., §ii. ; est. filicisliq.,ji. ; ol. lini, Oi. M. To be given fasting, after the animal has been kept for a few days on soft food. . In parasitic bronchitis in calves and lambs, oil of tur- Digitized by Microsoft® TURPENTINE 467 pentine is extensively employed, and maybe administered in doses of half an ounce to calves and one drachm to lambs, mixed vrith milk, and repeated at intervals of two or three days. For calves intra^tracheal injections are largely em- ployed, consisting of ol. tereb., 3i. to 3ii- ', ac. carbolic, 5ss. ; chloroform and glycerine, aa 3ss. By this means the parasites are directly acted on and destroyed. Oil of turpentine is very useful in cases of parasitic diarrhcea and arusmia in cattle, due to the presence of strongyli in the fourth stomach. It may be given in milk or mucilage, and combined with a preparation of iron. As an antidote to phosphorus, turpentine is employed in the form of the crude oil, which converts the poison into a harmless compound, and causes its elimination by the kidneys (see p. 275). Coutra-Indications. — In congestive and inflammatory conditions of the kidneys, and in gastritis, enteritis, etc., turpentine should not be prescribed. Dogs are particularly susceptible to the action of the drug, hence it should be administered in small doses, and the effects carefully watched. Externally, oil of turpentine is largely employed as a constituent of stimulating liniments, embrocations, etc. Its vesicating effect should be avoided, as it is likely to produce a blemish, besides causing excessive irritation, restlessness, and excitement in horses. The liniment of turpentine is extensively used as a stimulating application to rheumatic affections of joints and muscles. It is also applied as a mild counter- irritant to the walls of the chest in respiratory affections, and employed to prevent chilling during the process of keeping hot applications to the thoracic and abdominal regions. Digitized by Microsoft® 468 VETERINARY THERAPEUTICS Terebene. Produced by the action of sulphuric acid on oil of turpentine and distillation ; resembles the latter in its actions, but is less acrid and less liable to cause irritation of the kidneys. It is sometimes prescribed internally in cases of chronic bronchitis, and may be administered as an emulsion. Externally it is stimulant, antiseptic, and a deodorizer. Resin. The residue left after distillation of oil of turpentine from the crude oleo-resin ; is a favourite ingredient of diuretic masses and powders. The doses for horses and cattle are from gss. to |i. ■ Externally , it is employed in the form of ointment as a mild local stimulant and disinfectant to ulcers and un- healthy surfaces. The Unguentum Resinse, commonly known as 'digestive ointment,' is prepared by melting together — resiu, 4 ; yellow wax, 2; simple ointment, 8; almond oil, 1. Eesin is contained in many forms of plasters to impart firmness and adhesiveness. Fix Liquida — Tae. A bituminous liquid obtained from the wood of Pinus sylvestris and other species of Pinus by destructive dis- tillation. Preparations. Oleum Picis Lictuidse— Oil of Tar — obtained by distilling tar. Pix Nigra — Pitch — the residue remaining after the distillation of tar. Unguentum Picis Liauidae — Tar (by weight), 5 ; yellow wax, 1 ; almond oil, 1 ; melt together, and stir till cold. Aqua Picis — Tar Water — Stir a pint of tar with half a gallon of water for fifteen minutes, and decant. Action and Uses. — Externally , tar acts as a vascular stimulant and tissue alterative, and for such purposes is Digitized by Microsoft® TAR— OIL OF CADE— OIL OF JUNIPER 469 frequently employed in the form of ointment, or as a constituent of ointments and liniments in cases of dry scaly skin diseases. It is also valuable as an application for mange in both horses and dogs, and may be combined with sulphur and an oleaginous basis, the addition of an alkali rendering the preparation more efficacious. As a dressing for brittle hoofs in horses, often accom- panied by insufficient .growth of healthy horn, the oil of tar, mixed with vaseline, is a useful application. Internally, tar acts as a disinfectant and expectorant. It is a favourite palliative remedy in cases of chronic cough and broken-wind in horses, the method adopted being to place a certain amount of tar in the receptacle from which the animal's drinking-water is drawn. After a time this water is readily partaken of, and in our ex- perience such treatment is of value in conjunction with other details. Tar in such cases probably acts by favouring gastric digestion as well as by its expectorant effects. Pitch, administered in the form of bolus, is recom- mended by Professor Williams in the treatment of dry scaly skin diseases, such as pityriasis (' Principles and Practice of Veterinary Surgery '). Oleum Cadinum — Oil of Cade. Obtained by destructive distillation of the woody portions of Juniperus oxycedrus ; is an agreeable form of tar, and combined with soap and spirit it may be em- ployed in the treatment of chronic eczema and other skin affections of the dog. Juniperi Oleum— Oil of Junipee. Obtained from the fruit of Juniperus communis; resembles turpentine in its actions, but is less powerful. Digitized by Microsoft® 470 VETERINARY THERAPEUTICS It is believed to produce diuretic effects by stimulating the renal cells in a specific manner, increasing both solids and water. It may be employed as a diuretic in cases of dropsy, not depending on acute renal disease. The dose for horses is 3i. to 3ii-, and dogs, yf\Ji. to 1Tl_iv., given dissolved in spirit, and combined with saline diuretics. Oleum Eucalypti — Oil of Eucalyptus The oil distilled from the fresh leaves of Eucalyptus globulus, Eucalyptus amygdalina, and probably other species of Eucalyptus, the gum-tree from Australia. Doses. — Horses and cattle, 3i. to 3ii., dogs, TTl_ii. to ni_x., may be administered, dissolved in spirit, or in mucilage. In cases of septic diseases these doses should be increased and repeated at intervals. Actions and Uses. — Externally, oil of eucalyptus is a powerful antiseptic and disinfectant, and in the form of ointment (1 to 5) it forms a valuable surgical dressing. As an inhalation it proves of great service in bronchitis, allaying irritation, and preventing fcetor of the secretions. Internally it acts as an antipyretic and antiperiodic, resembling quinine to a certain extent. We have observed excellent results from its employ- ment in cases of influenza in horses complicated with bronchitis, and in cases of distemper in dogs, accom- panied by profuse and foetid nasal discharge. In such instances, frequent inhalations of the drug were em- ployed, along with its internal administration. Eucalyptus is excreted by the kidneys and lungs, and exerts antiseptic actions on the mucous surfaces of these regions. It is indicated in pyelitis, cystitis, and as it resembles other volatile oils in its action on the gastro- intestinal canal, it may be employed in certain affections of the stomach as a gastric disinfectant. Digitized by Microsoft® CAMPHOR 471 Camphora — Camphoe. A stearoptene obtained from the wood of Cinnamomum camphora, readily powdered if moistened with rectified spirit. Doses. — Horses, 3ss. to 3ii. ; cattle, 3ii. to 3iii. ; sheep, grs. X. to grs. xx. ; dogs, grs. ii. to grs. v. PreTparations. Spiritus Camphorse — 1 in 10 of rectified spirit. Doses. — Horses, §ss. to ji. ; cattle, §i. to gii. ; sheep, 3ss. to 3i. ; dogs, TT\_x. to ysy xxx. Linimentum Camphorse Compositum — Camphor, 20; strong solution of ammonia, 40 ; spirit, 120 ; oil of lavender, 1. Tinctura Camphorse Composita — See p. 394. ACTIONS OF CAMPHOE. (1) IMMEDIATE LOCAL ACTION. Externally camphor resembles to a certain extent the actions of oil of turpentine and other volatile oils. It is a feeble antiseptic, a stimulant to the local circula- tion, and a sedative to the nerves after primary stimula- tion. Internally it acts very much like volatile oils, increas- ing the local circulation, the saliva and the mucous flow in the mouth. In the stomach it acts as a carminative, and exerts reflex effects, stimulating the heart and nervous system. It possesses similar effects in the in- testines, and acts as an antispasmodic, besides lessening irritability of the mucous membrane. (2) SPECIFIC ACTION. A portion of the camphor administered is found un- changed in the organs and tissues ; the remainder appears to combine with glucose. Digitized by Microsoft® 472 VETERINARY THERAPEUTICS The chief action of camphor is exerted on the nervous system. In large doses it acts as a narcotic, and may induce convulsions. In moderate doses it stimulates the brain, spinal cord, respiratory functions, and the heart, the latter being also acted on in a reflex manner from the stomach. The diaphoretic effects described as occur- ring in man are not observed in veterinary patients. (3) BBMOTE LOCAL ACTION. Camphor is excreted by the respiratory organs un- changed, acting as an expectorant in a similar manner to turpentine. It is also excreted by the skin and kidneys. Medicinal Uses. — As a carminative, camphor is em- ployed in cases of diarrlicea in the form of the tinctura camphorae composita. It is recommended by some authorities in enteritis in combination with opium. In cases of bronchitis, both acute and chronic, it exerts beneficial effects by its expectorant action, and may be combined with spiritus aetheris nitrosi and belladonna, when cough is a prominent symptom. When the ad- ministration of fluids becomes dangerous, in consequence of violent fits of coughing, camphor may be given in the form of electuary, being combined with potass, chloras and extract of belladonna. Camphor is frequently employed as a constituent of various cough mixtures and powders, the following being a useful powder for recent cases : Camphor, pulv., ^ss. ; pulv. foL belladonnas, 3ii. ; potass, chlor., sii. ; pulv. anisi fruct., gss. This may be given twice daily in the food. In cases of irritable cough in dogs, often accompanying distemper, small doses of camphor in combination with squills and belladonna give favourable results. Externally. — Camphor is extensively employed as a constituent of various stimulating liniments. It may be Digitized by Microsoft® BENZOIN 473 combined with tincture of arnica and liq. ammoniae fort, (see p. 230), which makes a useful hniment. The com- pound camphor liniment is frequently used as a mild counter-irritant to the throat, thoracic walls, etc. The beneficial effects of camphor externally may be ascribed to its power of increasing the nutrition of injured or indurated parts, and relieving pain. Com- bined with chloral hydrate it forms an efficient local anodyne. Benzoinum — Benzoin. A balsamic resin obtained by incisions in the bark of Styrax ben;5oin and other species of Sty rax. Benzoin contains 12 to 15 per cent, of benzoic acid, a trace of cinnamic acid, two resins, and a volatile oil. Preparations. Adeps Benzoatus — 1 to 50 of prepared lard. Tinctura Benzoini Composita — ' Friar's Balsam ' — Benzoin, 8 ; prepared storax, 6 ; balsam of Tolu, 2 ; Socotrine aloes, 1^ ; spirit, 80. Acidum BenzDicum — Benzoic Acid — -Prepared from benzoin by sublimation. Benzoic acid is contained in tinctura camphorse composita (see p. 394). Ammonii Beuzoas — Prepared from benzoic acid and solution of ammonia. Sodii Benzoas — Prepared from benzoic acid and car- bonate of sodium. (1) IMMEDIATE LOCAL ACTION. Externally , benzoin and its preparations are antiseptics and disinfectants, also acting as slight stimulants to the vessels. They possess slight styptic properties. Internally, when inhaled in concentrated form, they act as slight irritants to the respiratory passages, while if diluted they are mild stimulants. Digitized by Microsoft® 474 VETERINARY THERAPEUTICS In the stomach, benzoic acid acts as a slight irritant ; its salts possess this effect in a less degree. (2) ACTION ON THE BLOOD, Benzoin and benzoic acid enter the blood in the form of benzoate of sodium ; the acid is partly converted into hippuric acid by combination with a molecule of glycoll, the same change occurring in the kidneys. (3) SPBOIPIO ACTION. Benzoic acid and its preparations are to a certain extent antipyretic, and are believed by some authorities to increase metabolism. (4) BEMOTE LOCAL ACTION. Benzoic acid is excreted by the kidneys, skin, and salivary glands, and probably by the respiratory organs. It increases the ilov7 of urine, and is removed by the kidneys partly unchanged, and partly as hippuric acid. It also stimulates the bronchial secretions, thus acting as an expectorant. Medicinal Uses. — Benzoic acid and its ammonium salt are recommended in cases of cystitis, with alkalinity of the secretion and pliospliatic deposits ; it is believed to produce beneficial effects by acidulating the urine and stimulating and disinfecting the mucous surfaces. As an Expectorant. — The compound tincture of benzoin is occasionally employed in cases of chronic bronchitis, in doses of ji. to gi.ss. for horses, and 3ss. to 3i. for dogs. Externally. — The compound tincture of benzoin was at one time extensively employed as a dressing for wounds under the familiar name of ' f^riar's Balsam.' Other more effective and less irritating antiseptic agents have now taken its place, but it is still occasionally used as a dressing for unhealthy wounds. Digitized by Microsoft® BALSAM OF PERU AND BALSAM OF TOLU 475 Balsam of Peru and Balsam of Tolu resemble benzoin in their actions ; both contain benzoic acid. Balsam of Peru is recommended by Dr. Fleming in the treatment of mange in house dogs ; it destroys the aoari, and relieves the itching and inflammation of the skin. It may be applied of the strength of 1 to 4 of alcohol. Myrrh resembles the other oleo-resins in its actions. It is sti- mulant, disinfectant, expectorant, and stomachic. Valerianae Rhlzoma — Valerian Ehizome. The dried rhizome and rootlets of Valeriana officinalis. Contains a volatile oil and valerianic acid. Preparatio7is. Tinctura Valerianae — -1 in 8 of proof spirit. Doses. — Horses, Ji. to §ii. ; dogs, 5ss. to 3i. _. . , . I Compounds of valerianic acid with Quininse valerianas ) Actions and Uses. — Valerian acts in a similar manner to other substances containing volatile oils, but has a more marked stimulant effect on the central nervous system. It is a powerful carminative, circulatory sti- mulant, and antispasmodic. Valerianic acid does not appear to possess the action of the volatile oil just men- tioned, so that the valerianates exhibit the actions of their bases. Valerian is said to have little efl:ect on horses and cattle even in large doses. In dogs it is occa- sionally prescribed in cases of chorea and epilepsy, but we have not observed any beneficial results from its employment. Digitized by Microsoft® 476 VETERINARY THERAPEUTICS Asaf oetida— AsAFCE tid a . A gum-resin obtained by incision from the living root of Ferula narthex and other species. Contains a volatile oil, resin and gum. Doses. — Horses, 3ii. to 3iv. ; cattle, gi. ; sheep, 5i. ; dogs, grs. V. to grs. xx. Preparation. Tinctura Asafoetida — 1 in 8. Dose. — Horses, §ss. to gi.ss. ; cattle, 5ii. ; dogs, n|_xx. to 3ss. Actions and Uses. — AsafcBtida resembles other volatile oils and gum-resins in its action on the alimentary canal ; but instead of possessing aromatic properties, it is very disagreeable to the taste and smell. It acts as a stimu- lant to the mouth and stomach, and reflexly as a ner- vine stimulant. It has a special action on the intestines, stimulating the muscular coat, and being antispasmodic. It is partly excreted by the lungs, acting as a stimulant and disinfectant expectorant. The chief use of asafoetida in veterinary practice is in cases of flatulent conditions of the intestines. It is some- times employed in the treatment of flatulent colic, com- bined with oil of turpentine, aromatic spirit of ammonia, and raw linseed oil. It was recommended by the late Professor Eobertson in cases of constipation and torpidity of the bowels in horses, in combination with aloes and nux vomica. Calbanum and Ammoniacum are gum-resins acting in a similar manner to asafoetida and other oleo-resins. Ammoniacum is sometimes pre- scribed as a disinfectant expectorant in cases of chronic bronchitis with profuse discharge. Digitized by Microsoft® CA PSICDM—Il USTARD 477 Capsici Fructus — Capsicum Feuit. The dried fruit of Capsicum fastigiatum. Distin- guished as chili pepper, and as cayenne pepper when ground. Preparation. Tinctura Capsici — 1 in 27. Actions and Uses. — Capsicum is a ]pungent stomachic, carminative, and stimulant. It is sometimes employed as one of the constituents of chlorodyne (see p. 338). Other varieties of peppers, viz., hlach and white peppers, resemble capsicum. They are often employed as popular remedies in country districts for colic in horses, being mixed with whisky or gin, etc. They possess local stimulant and aromatic effects on the mouth, stomach, and intestines, and during their excretion act as remote local stimulants of the circulation and nutrition in the urethra and rectum. Sinapis — Mustaed. A mixture of the powdered seeds of white mustard — Brassica alba — and of black mustard — Brassica nigra. Contains a bland fixed oil, and when this has been ex- tracted and the mustard mixed with water at 120° and distilled, the official volatile oil, oleum sinapis, is ob- tained. This has a penetrating odour and a blistering action on the skin, and as the seeds and powder of mustard are devoid of these irritating properties, the oil is believed to be developed by a decomposition of their constituents. Actions. — Mustard, apphed in the form of properly prepared paste to the skin, promptly acts as a rubefacient and nervous stimulant, causing increased local circulation, heat, and severe burning pain. This effect is followed by loss of sensibility of the part to other impressions and relief of previous pain. If the application be prolonged, vesication results by the production of local inflammation. Digitized by Microsoft® 478 VETERINARY THEMAPEUTICS Various effects on distant organs are produced, the heart, blood-pressure, respiration, and nerve-centres being stimulated by the first application of the agent, soothed during the stage of anaesthesia and relief of pain, while if vesication be severe depression will result (see section on ' Counter-irritation,' p. 197). Uses. — The chief use of mustard is as a counter-irritant in respiratory affections — that is, when the adoption of such means is indicated. The mustard should be made into a paste with water at a temperature of 100°, and rubbed well into the skin, and washed off with tepid water after fifteen or twenty minutes. In preparing the mustard, too hot water should be avoided, also agents such as vinegar, spirits, etc., should not be added, as the formation of the essential oil is thus prevented. Here we must caution the student against the indiscriminate or excessive use of mustard, especially in the case of well-bred horses or those with fine skins. If applied too severely it causes great irritation, followed by depression, and may produce a blemished condition of the skin. The cases in which counter-irritation will prove of service can only be ascertained by clinical experience. There is no advantage gained by applying the mustard in so severe a manner that great disorganization of the skin results ; such an occurrence should be rigidly avoided, as besides the risk of blemish it causes great depression of the system. As a general rule, if the patient is progress- ing favourably, counter-irritants should not be employed_ The indications for their use will be found at p. 201. In certain abdominal affections the application of mustard to the abdominal walls seems to give relief. As a popular emetic mustard is given dissolved in warm water to dogs, from one to three teaspoonfuls acting promptly as a local emetic. Digitized by Microsoft® CROTON OIL 479 CHAPTEE XIV. THE VEGETABLE TSl'^GTlOU— Continued. In this chapter those vegetable drugs acting as purgatives will receive notice. In veterinary practice but few vegetable purgatives are as yet in common use, in consequence either of their em- ployment not giving satisfactory results, or because they have not received sufficient trial. In human medicine a large variety of purgatives are employed, a combination of two or more being found of advantage. Oleum Crotonis— Ceoton Oil. The oil expressed from the seeds of Croton tiglium. The active principle of croton oil is obscure ; it is believed to contain a vesicating and a purgative principle distinct from each other. Doses. — Horses, n\^x. to TI)_xx. ; cattle, 3ss. to 3i- Prepm-atioji. Linimentum Crotonis — Croton oil, 1 ; oil of cajeput, 3J; spirit, 3^. Actions. — Externally, croton oil is a powerful irritant to the skin, and if freely used produces papules, followed by severe pustules, which are slow to heal and may leave a blemish. Internally, croton oil is a drastic cathartic, acting very rapidly, sometimes within one or two hours, producing frequent, full, and fluid dejections. It acts by direct irritation of the intestinal mucous membrane, and causes heightened peristaltic action, increased watery transuda- tion, and probably glandular hypersecretion. It has no special cholagogue action. The muscular excitement and consequent griping induced by the drug are believed Digitized by Microsoft® 480 VETERINARY THERAPEUTICS to commence before it has reached the duodenum, and are referred partly to a reflex action originating in irrita- tion of the gastric nerves. In large doses croton oil acts as an irritant poison, causing violent purgation and gastro-enteritis in all animals. The antidotes are opium and demulcents. Medicinal Uses. — In consequence of its violent effects, croton oil is but rarely employed as a purgative for horses. In cases where a speedy and complete evacua- tion of the bowels and a diminution of arterial pressure are demanded, such as in cases of phrenitis, meningitis, stomach staggers, etc., the drug may be given to the horse, combined with belladonna or hyoscyamus. In cases where the administration of a bolus or a drench is impossible, croton oil may be placed between the molar teeth, mixed with ext. belladonna. In dogs it should not be employed ; indeed, generally speaking, in all patients the use of this drug should be avoided as much as possible, and milder purgative agents, with the use of enemata, should be depended on to act on the bowels. In cattle, croton oil is an effectual purgative, and will often produce effects when other agents fail. At one time it was freely given in the treatment of that affec- tion known as 'fardel-bound,' but often with disastrous results, as the disease has been proved to be due to a condition of inflammation of the abomasum, a state in which violent purgatives are contra-indicated. Croton oil or other drastic purgatives should never be given in cases of inaction of the bowels depending on inflam- matory changes, a paralyzed condition of the intestinal walls, or intestinal obstruction. Externally, croton oil is employed as a counter-irritant for cattle in the form of the linimentum crotonis. Digitized by Microsoft® ELATERIUM—COLOCYNTH 481 Elaterium. A sediment from the juice of the fruit of Ecballium elaterium, the squirting cucumber. Contains the official active neutral principle elaterin. Doses. — Horses and cattle, grs. v. to grs. x. ; dogs, gr. j-V to gr. ^. Actions and Uses. — Elaterium is a powerful hydragogue purgative, producing very watery motions, with griping and considerable depression. It is but seldom employed for horses, but is prescribed for dogs in dropsical affec- tions and uraemia depending on renal disease ; it relieves the venous pressure by free evacuation of fluid into the bowel. It is recommended by Professor Williams in cases of acute congestion of the liver in the dog, in order to cause a drain from the portal system. Colocynthidis Pulpa — Colocynth Pulp. The dried fruit of Citrullus colocynthis. Contains a bitter glucoside, colocynthin, and a resinous powder, citrullin. Preparations. (1) Extractum Colocyntliidis Compositum — Colocynth pulp, 6 ; extract of Socotrine aloes, 12 ; resin of scam- mony, 4 ; curd soap, 3 ; cardamom seeds, 1 ; proof spirit, 160. Dose. — Dogs, grs. ii. to grs. v. (2) Pilula Colocynthidis et Hyoscyami— Colocynth pulp in powder, 1 ; Barbadoes aloes, 2 ; resin of scammony, 2 ; sulphate of potassium, \; oil of cloves, \; extract of hyoseyamus, 3 ; distilled water, a sufficiency ; mix. Dose. — Dogs, grs. v. to grs. xv., according to size. Actions and Uses. — Colocynth is a gastro-intestinal stimulant and powerful drastic, hydragogue cathartic, acting on the muscular coat, and increasing the secretions of the intestinal glands. According to Dr. Eutherford, it 31 Digitized by Microsoft® 482 VETERINARY THERAPEUTICS also acts as a powerful hepatic stimulant, rendering the bile more watery, but increasing the secretion of biliary matter. In large doses it is a gastro-intestinal irritant. Colocynth is always used in combination with milder purgatives and carminatives. It is seldom prescribed for horses, but is a useful purgative for dogs, in the form of the pilula colocynthidis et hyoscyami. Colocynthin or citrullin is recommended by Baum as a purgative for the horse. He administers 10 to 15 grains in the form of enema, combined with 6 ounces of glycerine and alcohol, and states that it occasions a prompt move- ment of the bowels; he has also observed satisfactory results from the administration of this agent to dogs and pigs. Cambogia — Gamboge. A gum-resin obtained from Garcinia Hanburii. Con- tains about 73 per cent, of a resinous substance, gambogic acid. Dose. — For cattle, gss. to Ji., given in combination with other purgatives. Actions and Uses. — Gamboge is a powerful hydragogue and drastic cathartic resembUng colocynth, but possesses no cholagogue action. It is also diuretic, being partly excreted by the kidneys. In consequence of its irritant drastic effects it is not prescribed for horses or dogs, but is occasionally employed in combination with other pur- gatives for cattle. Jalapa — Jalap. The dried tubercles of Ipomoaa purga, otherwise called Bxogonium purga. Contains 15 to 20 per cent, of the official resin, which is composed of two gluoosides con- volvulin and jalapin. Dose. — Dogs, grs. x. to 3i., according to size; pigs, gi. to giii. Digitized by Microsoft® JALAP-SCAMMONY—PODOPHYLLTN 483 Pre;parations. Tinctura Jalapse — 1 in 8 of proof spirit. Dose. — Dogs, 3ss. to sii. Extractum Jalapae — 2 in 1. Dose. — Dogs, grs. v. to 3ss. Actions and Uses. — Jalap is a hydragogue cathartic producing copious watery discharges. According to Dr. Eutherford it is a moderately powerful hepatic, and a powerful intestinal stimulant. Jalap has but little action on horses or cattle, 2 to 4 ounces having but a slight effect on the bowels, while increasing the activity of the kidneys according to Moiroud. For dogs and pigs it is a useful purgative, and may be advantageously combined with calomel and a carminative. Scammony. A gum-resin obtained from the root of Convolvulus scammonia ; resembles jalap in its actions, but is more irritant and liable to gripe. It is a powerful stimulant of the intestinal glands, and to a less degree of the liver. It is not prescribed alone, but is an important ingredient of the pilula colocynthidis et hyoscyami (see p. 481). Podophylli Rhizoma — Podophyllum Ehizome. The dried rhizome and rootlets of Podophyllum pelta- tum, American May apple. Preparations. Podophylli Eesina — Eesin of Podophyllin — contains an active principle, picropodophyllin. Doses. — Horses, 3i. ; dogs, gr. | to grs. ii. ; generally combined with hyoscyamus and calomel. Tinctura Podophylli — 1 grain in 1 fluid drachm of recti- fied spirit. Doses. — Horses, gss. to §i,ss. ; dogs, TH_xv. to 3i. Digitized by Microsoft® 484 VETERINARY THERAPEUTICS Actions and Uses. — Podophyllin, according to some authorities, acts as a purgative and cholagogue in horses and dogs, -while others state that its action is very un- certain when used alone. On dogs it is said to act as a powerful hepatic stimulant, and in large doses as a violent purgative. The purgative effect appears to be due to stimulation both of the muscular coat and the glands of the intestine, as well as to increase of the biliary flow. Podophyllin may be employed in combination with calomel and hyoscyamus in cases of torpidity or conges- tion of the liver. Aloe Barbadensis — Babbadoes Aloes. The juice when inspissated which flows from the trans- versely cut bases of the leaves of Aloe vulgaris, Barbadoes and Cura9oa aloes. Doses. — -Horses, 3ii- to 3vii., according to size and re- quirements ; cattle, Ji. to 3ii. ; dogs, grs. xv. to grs. xxx. Preparation. Aloin — a crystalline substance extracted from aloes. Doses. — Horses, 3i. to 3ii. ; dogs, grs. iii. to grs. x. Actions. — Aloes acts upon the stomach and intestines as a bitter and purgative. The former effect resembles that of calumba and other bitters (see p. 452). The purgative action of aloes demands special atten- tion, as it is the drug chiefly employed as a cathartic for the horse. It increases both the peristaltic movements and intestinal secretions, acts chiefly on the large intes- tines, and is a stimulant of the biliary flow. The action of aloes as a purgative is very slow, espe- cially if the intestinal contents are not previously in a soft condition. The ordinary dose in an animal not pre- pared generally takes sixteen to twenty-four hours to Digitized by Microsoft® ALOES 485 operate. If the animal be properly prepared, purgation may be produced in about twelve hours. In some rare instances aloes produces diuresis instead of purgation. It is believed to stimulate the pelvic cir- culation generally as well as that of the rectum. Aloes is absorbed and enters the circulation, and is excreted chiefly by the intestinal glandular apparatus. In ruminants the action of aloes is often uncertain, and large doses have been administered without producing purgation. This peculiarity is believed to depend on the fact that the chief action of aloes is exerted on the large intestines, which are not developed to the same extent in ruminants as in horses. In dogs, aloes is slow and uncertain when administered alone. Large doses are often tolerated as compared with those suitable for man. Medicinal Uses. — Aloes is the purgative in general use for horses. It is by no means an ideal purgative, as the length of time which it takes to act, and the nausea induced by the drug, are great drawbacks. However, in our present state of knowledge we are unable to suggest a more reliable or safer purgative agent, but it seems highly probable that in the future a combination of pur- gatives will be discovered which will act in a shorter space of time and with less nausea than aloes given alone. Aloes is best given in the form of a properly prepared bolus, care being taken in its preparation not to apply too high a temperature in melting the ingredients. It is made up in the form of a mass containing a small amount of some volatile oil to prevent hardening and drying ; from this the required quantity is made into balls. It is advisable to combine two drachms of ginger and half a drachm of the extract of hyoscyamus or belladonna with Digitized by Microsoft® 486 VETERINARY THERAPEUTICS the physic ball so as to avoid the tendency to griping. Few veterinary surgeons now go to the trouble of pre- paring their own aloetic masses, as there are reliable wholesale chemists who make up the required formula in a satisfactory manner, and send out the physic balls neatly covered with gelatine. Before a purgative ball is administered it is necessary to have the horse properly prepared, and to have pre- cautions taken ag to after-treatment, as stated at p. 93, under the heading of purgatives ; above all things, cold water should be prohibited, and when the physic has commenced to act, perfect rest in the stall is imperatively necessary, and any green foods, roots, etc., should be rigidly interdicted. In cases where full purgative effects are required, it is of advantage to combine calomel with the aloes in the proportion of half a drachm of the former with four drachms of the latter ; this is especially recommended in cases where it is difficult to produce purgation with the ordinary dose of aloes. Too large a dose of aloes, or neglect of the necessary precautions already mentioned, may induce a condition of superpurgation, and in some instances great constitu- tional disturbance occurs, with congestion of the intestinal mucous membrane and death from exhaustion, laminitis sometimes occurring as a complication. In some cases even a moderate dose of aloes will induce superpurgation and serious symptoms, in spite of all necessary precautions, these effects probably depending on individual idiosyncrasies to the drug. We often observe that purgation continues for a longer period than usual, but if no constitutional disturbance be present, and if the pulse is regular, no danger is to be appre- hended. But if the pulse becomes frequent and feeble, Digitized by Microsoft® ALOES 487 and the purging constant, with symptoms of uneasiness, with or without distension of the abdomen, then steps must be taken immediately to overcome the injurious effects of the purgative. In cases where death occurred after the excessive action of aloes. Professor Williams gives the following post- mortem appearances : ' Congestion of the intestinal mucous membrane generally, concentrated in many cases in that of the csecum caput coli ; a thick tarry appear- ance of the blood, and extreme blackness, congestion, or apoplexy of the lungs, the blood being, as it were, de- prived of its watery elements, altered in its composition, rendered too viscid to circulate through the pulmonary capillaries, and so altered chemically as to render it unfit for perfect oxidation ' (' Principles and Practice of Vete- rinary Medicine '). In the treatment of superpurgation due to the effects of aloes, great discrimination is necessary to avoid check- ing the action of the intestines suddenly, as congestion of the mucous membrane may be induced. If the horse, although purging freely, appears moder- ately lively, and the countenance natural, without any marked change in the pulse, then he should be allowed well-boiled thin flour-gruel, and be warmly clothed, and cold fluids of all kinds avoided. If the purging still con- tinues, it should be gradually overcome, and Professor Williams recommends two ounces each of tr. opii and creta preparata in a quart of flour-gruel every three or four hours until the purging is checked. We have found this treatment of great value in such cases. If prostration be present stimulants should be given, the best in our experience being brandy and port wine, three wineglassfuls of each being combined with the flour-gruel. Digitized by Microsoft® 488 VETERINARY THERAPEUTICS It becomes a matter of very great importance to the veterinary surgeon if serious or fatal results occur after he has prescribed the usual dose of aloes for a horse. He should be especially careful to ascertain that the animal has been properly prepared, and that the intestines are in a fit state, before administering the purgative. He should also give clear instructions to the groom or attend- ant with reference to the care of the animal, as many cases of ill effects after aloes are due to neglect of the ordinary precautions, and the veterinary surgeon's repu- tation suffers in consequence. In prescribing aloes, we must remember that a proper dose is necessary, as an insufificient amount is apt to be longer retained in the system, producing irregular eifects and an excessive degree of nausea. If the dose does not takeefi'ect in twenty-four hours, moderate walking exercise should be ordered ; but when it commences to act, the horse should be kept at rest, and not worked until the physic has 'set.' In cases where the ordinary dose of aloes fails to act, it is not safe to administer another until forty eight hours have elapsed. If immediate effects are necessary, we prefer to depend on the use of raw linseed oil, and the administration of enemata by means of the long rectum tube. Aloes is recommended by many practitioners in the treatment of spasmodic colic depending on the presence of irritating ingesta in the alimentary canal. The difficulty of arriving at a correct diagnosis in cases of abdominal pain, however, makes us hesitate before prescribing a drug which, if the case happens to be the commencement of a more serious condition, will destroy the chances of a successful termination, and tend to a fatal result. Digitized by Microsoft® ALOES 489 We have to consider, too, the time which aloes will take to act in an animal without any preparation, and hence the safer and more rational treatment is to relieve the pain by the administration of an anodyne, and to combine with it a suitable dose of raw linseed oil; by this means, no matter what the result of the case happens to be, no possible injury will be inflicted by treatment. If we were enabled to accurately diagnose the cause of abdominal pain to be the presence of irritating ingesta, then indeed the administration of the purgative ball would be rational treatment ; but clinical experience and post-mbrtem examinations teach us that, although the primary symptoms may point to a simple case of spas- modic colic, they may in reality be the precursors of a serious condition in which strong purgaitives are entirely contra-indicated. In cases of impaction of the colon in the horse. Professor Williams recommends an enema composed of 2 ounces of aloes dissolved in a pint of hot water, and administered at a temperature of 90° Fahr. with the long rectum tube. Centra-Indications. — Aloes is contra-indicated in irri- table or inflammatory conditions of the alimentary canal, also in respiratory affections, in influenza, and all debili- tated conditions of the system. In laminitis only a moderate dose should be given, as too large an amount is likely to increase the already in- flamed condition of the laminae. If a horse exhibits the slightest sign of a catarrhal afi'ection or of a cough, aloes should not be prescribed, as it may induce superpurgation, or may weaken the system and so render the animal in a condition less able to with- stand the effects of any respiratory disease which may follow. Digitized by Microsoft® 490 VETERFNART THERAPEUTICS Aloes is occasionally prescribed as a bitter tonic, and is given in small doses, combined with other bitters and aromatics, or with a mineral tonic, such as sulphate of iron. In cattle practice, aloes is sometimes prescribed along with other purgatives, usually in the form of a solution. We have observed favourable results in some cases from its employment, where the ordinary purgatives did not appear to produce any effect. Li canine practice, aloes is not prescribed alone ; it enters into the composition of the compound colocynth and hyoscyamus pill, which is an effectual purgative for the dog. Socotrine and Cape Aloes are varieties not employed in veterinary practice. Aloin, in doses of two drachms, has been found to act as a reliable purgative in horses by some practitioners, causing less dulness, nausea, and griping than aloes. Others have not recorded such satisfactory results from its use. [Senna. The dried leaflets of various species of Cassia ; is not employed in veterinary practice. It acts as a purgative by stimulating the muscular coat of the intestine, pro- bably by reflex action from the mucous surface of the bowel, the colon being chiefly acted on. Rhei Radix — Ehubaeb Eoot. The dried root of Eheum palmatum and other species. Contains 3 to 4 per cent, of cathartic acid, the purgative constituent of senna ; also rheo-tannic acid, possessing astringency, and a bitter colouring matter, chrysophan. Actions and Uses. — In small doses rhubarb, given to dogs, is a bitter stomachic and intestinal astringent. In Digitized by Microsoft® RHUBARB- CASTOR OIL 491 larger doses it causes purgation by stimulating the intes- tinal movements and the liver ; the cathartic acid at first exerting its influence ; afterwards an astringent effect is produced. According to Moiroud, even in large amounts rhubarb has no purgative effect on horses or cattle. As a purgative and cholagogue for the dog, it may be given in doses of grs. xv. to grs. xxx., combined with either calomel or jalap. In cases of obstinate diarrhoea in foals and calves, 2 drachms each of rhubarb and carbonate of magnesia, with 10 to 20 grains of opium, given twice a day in well- boiled wheat-flour gruel, often give favourable results, acting as stomachics and astringents. Oleum Ricini — Castoe Oil. The oil expressed from the seeds of Eicinus communis. The bulk consists of ricinoleate of glyceryl. Doses. — Cattle, O.i. ; sheep and pigs, |ii. to giv. ; dogs, §ss. to §ii. ; foals, |i. to gii. Actions and Uses. — Externally, pure castor oil is bland in its nature, resembliug almond oil. It acts as a local sedative and protective, and is often applied to the conjunctiva to lessen irritation after the removal of foreign bodies from the eye, or after injuries by caustic substances to the cornea or conjunctiva. Internally, pure castor oil is a simple purgative, mild and painless in its effects. It is believed to act by stimulating the muscular coat and intestinal glands, but not the liver. It produces no effect on the stomach, but if gastric irritation be present, or if the oil is not pure, it will cause nausea and vomiting in dogs. On reaching the duodenum, castor oil is decomposed by the pancreatic juice, and the ricinoleic acid commences to act. It causes purgation also when administered as an enema. Digitized by Microsoft® 492 VETERINARY THERAPEUTICS For the horse, castor oil is an uncertain purgative, pro- ducing much nausea, and cases are recorded where full doses caused serious symptoms of superpurgation. For foals, however, it often acts very effectually, and is pre- scribed in cases of retention of the meconium ; it may also be administered in the form of enema with advantage in such cases. It should be combined with a dose of sweet spirits of nitre, and a carminative, such as oil of peppermint. In cases of diarrhoea due to the presence of irritating ingesta, both in foals and calves, a dose of castor oil should be the first step in treatment. Li cattle, it is an effectual purgative, the chief draw- back to its employment being the loss of appetite, and degree of nausea induced. It is of advantage to com- bine castor oil and raw linseed oil in cases of arrested action of the bowels in cattle, enemas of the same being also of service. In dogs, castor oil is indicated in cases of obstinate constipation and in intestinal obstruction, being given in the form of enema as well as by the mouth. It is of advantage to combine half doses of olive oil and castor oil, and to administer the enemas by means of a long gum-elastic rectum tube. Unfortunately, in cases of this nature the stomach is usually in a very irritable condition, and any oily substances given by the mouth are quickly expelled by vomiting. It is necessary to prepare a special mixture of castor oil in such cases, the B.P. mistura olei ricini, as follows, often acting well : Castor oil, 6 drachms ; oil of lemon, 10 minims ; oil of cloves, 2 minims ; syrup, 1| drachms ; solution of potash, 1 drachm ; orange-flower water, to produce 2 ounces. The dose is from J to 2 ounces, repeated at intervals until effects are produced. The addition of a small dose of sweet spirit of nitre Digitized by Microsoft® LINSEED OIL 493 also renders castor oil more palatable. It is of import- ance to prescribe only the refined and pure castor oil, in order to avoid irritating and nauseating effects. Oleum Lini — Eaw Linseed Oil. The oil expressed in Britain without heat from linseed — Linum usitatissimum, flax. In prescribing it is im- portant to remember that boiled linseed oil is used in the arts as a drying oil, and for certain purposes litharge is added during the boiling, so that the boiled oil may con- tain lead and exert toxic effects. The raw linseed oil should be procured as fresh as possible. Doses. — Horses, O.i. to O.i.ss; cattle, O.i.ss. to O.ii. ; sheep and pigs, §iv. to gvi. ; dogs, §i. to gii. Actions and Uses. — In full doses linseed oil acts as a mild purgative. It is devoid of irritating effects, and is extensively employed in cases where active purgatives, such as aloes, are contra-indicated. In the form of enema it is an agent of great value in all animals, and should be administered by means of the long rectum tube in oases of intestinal obstruction depending on impaction of the colon ; by this method we have observed the most satisfactory results. One drawback to the use of linseed oil is the nauseating effects which it is apt to produce, and interference with appetite. For this reason we should avoid the adminis- tration of large amounts by the mouth, and adopt the method by enema, the long rectum tube enabhng us to propel the oil into the colon. In cattle practice, linseed oil is of great service in a large variety of cases. By softening the gastric contents it often produces beneficial effects when purgatives such as sulphate of magnesia fail. In impaction of the ojnasum and inflammation of the ahomasvm, conditions frequently associated, large doses Digitized by Microsoft® 494 VETERINARY THERAPEUTICS of linseed oil, combined with belladonna and glycerine, forms the most reliable treatment, as the exhibition of strong purgatives seldom gives relief, but tends to increase the existing condition. In hcemo-albuminura or red water, linseed oil is indi- cated, if the saline purgative usually administered at the commencement of the affection fails to move the bov?els. Linseed oil is also a convenient menstruum for the ad- ministration of irritant substances, such as oil of turpen- tine or croton oil. It is also a useful agent as a demulcent in cases of irritant poisoning. In dogs, linseed oil is apt to cause nausea and vomiting. Linseed oil is administered to horses in a bran-mash as a digestible nutrient, in amounts of one or two wineglassfuls ; some take it with avidity, others refuse it. It is very useful in cases where the bowels are inclined to be con- stipated, and the animal is in an unthrifty condition. In cases of broken wind it is prescribed with limewater, and is useful as a palliative remedy. Externally linseed oil forms an effectual basis for lini- ments for mange in horses. Mixed with equal parts of limewater it forms carron oil, which is a valuable appli- cation to burns and scalds. Cascara Sagrada. The dried bark of Ehamnus purshiana. Preparations. Extractum Cascarse Sagradae — Alcoholic and aqueous. Dose. — Dogs, grs. ii. to grs. x. Extractum Cascarse Sagradae LioLuidum — 1 in 1. Dose. — Dogs, 3ss. to gii. Actions and Uses. — Cascara sagrada in small doses acts as a tonic and stomachic. In large doses it is an Digitized by Microsoft® SYRVP OF BUCKTHORN— TARAXACUM 496 aperient, and if freely given to dogs is cathartic. It is useful in chronic constipation in dogs, and may be given in a single full dose, or in divided doses of ten to tvrenty minims three times a day. Syrupus Rhamni — Syeup op Buckthoen. Prepared from the recently expressed juice of Rhamnus catharticus, common buckthorn. Dose. — Dogs, §i. to gii. Actions and Uses. — Syrup of buckthorn acts as a mild cathartic to dogs, and is employed as an adjuvant to pur- gative mixtures. It is also used to disguise the taste of bitter or nauseous drugs in mixtures. Taraxacum. Obtained from the root of Taraxacum of&cinale, dande- lion root ; is a simple hitter, and a mild laxative in the case of dogs. At one time it was believed to act as a cholagogue, but according to Dr. Eutherford, it is a very feeble stimulant of the liver. It may be given to dogs in doses of ni_xv. to 3ii. of the liquid extract. Euonymin. Obtained from the root bark of Buonymus atropur- pureus. Actions and Uses. — Euonymin is a hepatic stimulant, a direct cholagogue, and a mild cathartic. It has been ad- ministered to the dog in doses of grs. ii. to grs. iv. of the dry extract in cases of hepatic derangements and jaundice, and seems likely to be a useful agent. The dose of the tinctura euonymi is from TTl_x. to ITLxl. for similar cases. Digitized by Microsoft® 496 VETERINARY THERAPEUTICS .CHAPTBE XV. THE VEGETABLE 'K.VSG^'DOM.— Continued. Filix Mas— Male Fben. The rhizome, with the persistent bases of the petioles, of Aspidium filix mas. Preparation. Extractum Filicis Lic[uiduni — ' Oil of Male Fern.' Doses. — Horses and cattle, 3ii- to Svi. ; dogs, Tf\^x. to Tll_xxx. Administered in milk or in emulsion. Actions and Uses. — Male fern is an active anthelmintic, being especially destructive to the tapeworm. In large doses it acts as an irritant, and may cause gastro-enteritis in dogs. It may be given to the horse in combination with half a dose of ol. terebinthinse in raw linseed oil. For the dog it may be combined with areca- nut, and given dissolved in milk. It is of advantage to administer a purgative afterwards in order to assist in the removal of the parasites. Santoninum— Saktonin. A neutral crystalline principle obtained from the dried unexpanded flower-heads of Artemisia maritima, worm- seed. Doses. — Horses, 333. to si. ; dogs, grs. ii. to grs. v. ; given with an oleaginous purgative. Actions and Uses. — Santonin is an effectual vermicide, particularly destructive to round and thread worms, but having little effect on the tapeworm. It is absorbed into the blood as sodium santonate, and in full doses may Digitized by Microsoft® SANTONIN— ARECA 497 cause disturbance of consciousness in dogs, with giddi- ness, vomiting, and convulsions, and great constitutional disturbance. These effects should be carefully avoided by regulating the dose according to the size of the animal. Santonin is excreted by the kidneys as an obscure pro- duct of its oxidation in the system, and causes slight diuresis. It colours acid urine greenish-yellow, and alkaline urine red or purple. Areca. The seed of Areca catechu, the betel-nut tree. Doses. — Dogs, grs. xv. to 3ii. ; given shaken up with milk. Action and Uses. — Areca-nut is an astringent and ver- micide, acting chiefly on the tapeworm. Previous to its administration a purgative should be administered so as to clear out the intestines ; the drug should then be given to the dog after a few hours' fasting, and is best administered in milk, a second purgative being afterwards necessary to cause expulsion of the parasite. In treating the dog for tapeworm, it is of advantage to combine areca-nut with the extract of male fern. A variety of anthelmintics are, in addition to those mentioned, employed in human medicine, but are seldom prescribed in veterinary medicine. Among these we may mention kousso, kamala, spigelia, pomegranate root bark, etc 32 Digitized by Microsoft® 498 VETERINARY THERAPEUTICS CHAPTER XVI. THE VEGETABLE KINGDOM— Co«teHierf. Acidum Tannicum— Tannic Acid, Tannin. An acid extracted from galls. Galls are excrescences on Quercus lusitanica, a shrubby species of oak, caused by the puncture and deposit of ova of Cynips gallse tinc- toria. Doses. — Horses, 3ss. to 5ii. ; dogs, grs. ii. to grs. x. Incompatibles. — Gelatine, mineral acids, alkalies, per- salts of iron. Pre2oaration. Glycerinum Acidi Tannici— 1 to 4, with the aid of heat. Acidum Callicuni — Gallic Acid. Prepared by boiling 1 part of powdered galls with 4 parts of dilute sulphuric acid for half an hour, strain- ing and purifying. Doses. — Same as those of tannic acid. Iiicompatibles. — Spirit of nitrous ether, metallic salts, including persalts of iron. Tannic acid is the glucoside to which oak bark, galls, logwood, and many vegetable astringents owe their pro- perties. Actions. — Tannic and gallic acids differ only in the degree of their action, but gallic acid has no astringent taste, does not precipitate solutions of gelatine, and hence possesses no local astringent properties. The ac- tion of tannic acid and of the many substances containing it depends chiefly upon its property of precipitating albumin and gelatine. Digitized by Microsoft® TANNIC AND GALLIC ACIDS 499 Applied to the broken skin or to exposed mucous sur- faces, it condenses the albuminous and connective tissues, coagulates the fluids, reduces the sensibility of the nerves, and compresses the vessels by constringing the connective tissues, thus diminishing the circulation through them. It also coagulates blood if applied in a concentrated form. Tannic acid thus acts as a powerful indirect styptic and constringent. It does not cause active contraction of the vessels like lead and other agents, but dilates them, and by an indirect constringent influence this effect is then more than neutralized. In the mouth tannic acid causes dryness of the tongue and throat, with thirst, the parts being constringed and partially anaesthetized. In the stomach tannic acid precipitates the pepsin and the albumins of the gastric juice, in full doses it con- • stringes the mucous membrane, reduces the circulation, and diminishes the secretion. In the intestines the astringent effect of tannin is con- tinued, hence its employment, or that of substances con- taining it, in cases of diarrhoea, etc. During its passage along the alimentary canal portion of the tannin is converted into gallic acid, which enters the blood, the remainder being excreted in the faeces. Tannin enters the blood as gallic acid, but we have no definite knowledge as to any further astringent effect on the vessels or coagulating influence on the blood. If injected directly into the veins tannic acid causes clotting and embolism, followed by death. The specific action on the tissues is believed to depend altogether on gallic acid, the effects being astringent and styptic. Tannic and gallic acids are excreted chiefly as the latter, partly as pyrogallic acid, in the urine, which it Digitized by Microsoft® 500 VETERINARY THERAPEUTICS darkens in colour. Some authorities believe that these agents have the power of arresting renal haemorrhage, but this action is doubtful. Medicinal Uses. — In relaxed conditions of the pharynx and throat, tannic acid is applied locally in the form of glycerinum acidi tannici, and gives favourable results. In hamorrhage from the stomach, full doses of the acid act as direct styptics. In diarrJicea, dysentery, tannin or its compounds are frequently prescribed, the latter being preferred, such as catechu or kino, and may be combined with antacids and opium. As an antidote to antimony and alkaloids, such as morphine, strychnine, etc., tannic acid is employed, as it forms insoluble compounds, a purgative being afterwards given, and an emetic in the case of dogs. Externally tannic acid, combined with glycerine and water, is recommended in the weeping stages of eczema. It is also employed as an application to ulcerated sur- faces, as it condenses the superficial layer of cells, coagulates the discharge, and is believed to possess a disinfectant action besides. Gallic acid, in the form of the unguentum gallse cum opio, is employed in the treatment of haemorrhoids. Pyrogallic Acid. A body obtained from gallic or tannic acid by carefully heating; possesses a powerful affinity for oxygen, and thus acts as an antiseptic and disinfectant in 1 to 2| per cent, solutions. It also acts as a caustic and local stimulant. It has been recommended in cases of psoriasis, and also in the removal of malignant growths. In toxic doses it causes vomiting, purging, and general nervous depression in dogs, and possesses a destructive influence on the red corpuscles of the blood, which be- comes of a brownish appearance and readily coagulates. Digitized by Microsoft® CATECHU— KINO— LOGWOOD 501 Catechu — Catechu. An extract of the leaves and young shoots of Uncaria gambier. Doses. — Horses, 3i. to 3iii. ; cattle, 3ii. to 3vi. ; sheep and pigs, gss. to gi. ; dogs, grs. v. to grs. xx. Incompatibles. — The alkalies, metallic salts, and gela- tine. Actions and Uses. — Catechu resembles tannic acid in its actions. It is employed as an astringent in cases of persistent diarrhma and dysentery in all patients, and may be combined with opium, chalk, and ginger, and repeated at intervals if necessary, it is best adminis- tered in well-boiled flour gruel. Kino — Kino. A juice obtained from the trunk of Pterocarpus mar- supium ; closely resembles catechu in its actions, and may be employed for similar purposes, and in the same doses. In the form of the pulvis kino compositus — Kino, 15 ; opium, 1 ; cinnamon, 4 — it is a useful agent for obstinate diarrhoea in dogs, and may be prescribed in doses of grs. V. to grs. xx. Haematoxyli Lignum— Logwood. The sliced heart-wood of Haematoxylon campechianum. Preparation. Decoctum HsBmatoxyli — 1 in 20 with \ of cinnamon. Doses. — Horses, gviii. to gx. ; cattle, §x. to §xv. ; dogs, gss. to gi.ss. Actions and Uses. — Haematoxylon possesses the astrin- gent action of tannic acid, and may be employed in the same class of cases. It forms a most effectual astringent in some cases of obstinate diarrhea in cattle, often Digitized by Microsoft® 502 VETERINARY THERAPEUTICS succeeding when other agents have failed. It is fre- quently used as an empirical remedy in the treatment of ' red water ' in cattle, some stock-owners attributing remarkable success to its employment. Hamamelidis Cortex— Hamamelis Baek. The dried bark of Hamamelis virginica, the witch hazel. Hamamelidis Folia. The dried leaves of Hamamelis virginica. Preiparations of Hamamelis Bark. Tinctura Hamamelidis— 1 in 10 of proof spirit. Doses. — Horses and cattle, §ss. to gii. ; dogs, lT|_v. to 3i- Extractum Hamamelidis Liquidum— Hazeline — 1 in 1. Doses.— Horses and cattle, 3ss. to ;^ii. ; dogs, TTl_v. to nix. Actions and Uses. — HamameUs is astringent and hcemostatic both locally and remotely. It is prescribed internally in cases of passive haemorrhage, such as epis- taxis, haemoptysis, hasmatemesis. It is also recom- mended in the treatment of diarrhoea, dysentery, etc., and in diseases dependent upon an unhealthy condition of the mucous membrane of the vagina, intestinal canal, bladder, and urethra ; but clinical experience with the drug has not yet been sufficient to justify these claims. Externally, it forms a useful non-irritating styptic. Ipecacuanlia — Ipecacuanha. The dried root of Cephaelis ipecacuanha. Contains from J to 1 per cent, of emetene, which is its active principle. Doses. — Horses, gi. to 5i.ss. ; dogs, gr. ss. to grs. ii. As an emetic for dogs, grs. x. to grs. xxx. Digitized by Microsoft® IPECACUANHA 503 Preparations. Pulvis Ipecacuanhse Compositus — ' Dover's Powder ' — ipecacuanha, 1 ; opium, 1 ; sulphate of potassium, 8— (linlO). Doses. — Horses, 3i. to 3iii. ; dogs, grs. v. to grs. xv. Vinum Ipecacuanhse — An acetic extract, dried, powdered, dissolved in sherry, and filtered (1 in 20). Dose. — Dogs, as an expectorant, ITLv. to IT^xxx. As an emetic, 3iii. to 3vi. Actions and Uses. — Externally, ipecacuanha acts as an irritant to the skin and exposed mucous membranes. Internally. — In the stomach in small doses it is a gastric stimulant, increasing local circulation and secre- tion. In the dog, ipecacuanha in doses of 16 to 30 grains acts as an emetic, both by its local effect on the stomach as well as by its action on the vomiting centre in the medulla ; it is thus both a direct and an indirect emetic. In the intestines ipecacuanha also exerts stimulating effects, and increases the flow of mucus ; in large doses it may act as an irritant. In cases of dysentery it has the power of arresting the inflammatory action in the intestine, and checking the liquid and blood-stained evacuations, and for such pur- poses is given in large doses frequently repeated. Ipecacuanha is excreted by the various mucous mem- branes, including those of the bronchi, the stomach, the intestines, also by the liver. On the bronchi it causes increased secretion and stimulates the nerves, thus acting as an expectorant. It has a remote action on the liver, and acts as a direct cholagogue. We do not observe any diaphoretic effect in our patients from the employment of ipecacuanha, such as is described as occurring in man. The chief pm-pose for which ipecacuanha is used in Digitized by Microsoft® 504 VETERINAUY THERAPEUTICS veterinary practice is as an expectorant, in the dry stages of bronchitis. It is prescribed in combination with liq. ammon. acet., and frequently repeated, and is believed to promote secretion of bronchial mucus. It may also be employed with benefit in the form of ' Dover's Powder,' and this preparation has been recommended in cases of dysentery in all patients. Buchu Folia — Buchu Leaves. The dried leaves of Barosma betulina and other species. Preparations. Infusum Buchu — 1 in 20. Doses. — Horses, gviii. to §x. ; dogs, |i. to giL Tinctura Buchu — 1 in 8 of proof spirit. Doses. — 5ii- to Siii- J ^ogs, 3i. to Jii. Actions and Uses. — Buchu is a mild tonic and diuretic, and exerts astringent effects on the bladder and urino- genital mucous membrane. Its chief use is in cases of irritation of the bladder and urethra, also in cystitis, and in inflammatory affections of the pelvis of the kidney. It relieves pain, reduces irritability, and promotes healing and cessation of the muco-purulent discharge. It may be combined with hyoscyamus and bicarbonate of potas- sium, or mixed with linseed-tea or barley-water. Pareira, TJva Ursi, and OoUinsonia Canadensis are agents possessing similar actions and uses to buchu. Digitized by Microsoft® CINCHONA— QUININE 505 CHAPTBE XVII. THE VEGETABLE KINGDOM— CoKfeViiierf. Cinchona. Obtained from the bark of different species of Cinchona. Cinchona bark contains four alkaloids : (1) Quinine ; (2) cinchonine ; (3) quimdine ; (4) cinchonidine. The yellow cinchona bark usually contains the largest amount of quinine, of which it should yield 2'5 to 3'8 per cent. The astringent principle of cinchona depends on cincho- tannic acid ; this turns green with persalts of iron. Incompatibles. — Ammonia, limewater, metallic salts, gelatine. Doses. — Horses, 3ii. to a^y. ; cattle, §i. to gii. ; dogs, grs. X. to grs. xv. Preparations. Tinctura Cinclionse — 1 in 6 of proof spirit. Doses. — Horses, §i. to gii. ; dogs, 3ss. to 5i. Tinctura Oinchonse Composita — Eed cinchona bark, 2 ounces ; bitter orange-peel, 1 ounce ; serpentary, h ounce ; saffron, 55 grains ; proof spirit, 1 pint Doses. — Similar to those of tr. cinchona. Quininae Sulphas — Sulphate op Quinine. Prepared from the powder of various kinds of cinchona bark, with subsequent neutralization of the alkaloid by sulphuric acid. Soluble in 700 or 800 parts of cold water, but readily dissolved in water by the addition of a small amount of dilate sulphuric acid (one minim will dissolve each grain). Incompatibles. — Alkalies and their carbonates, astrin- gent infusions, and substances containing tannin. Doses. — As a tonic; horses, grs. xx. to 3i. ; dogs, gr. i. to grs. V. ; as aji antiperiodic and antipyretic : horses, 5ii. to 5iv. ; dogs, grs. v. to grs. xx. Digitized by Microsoft® 506 VETERINARY THERAPEUTICS Quinina Hydrochloras — Hydeochloeatb of Quinine. Prepared in a similar manner to sulphate of quinine, hydrochloric acid being substituted for sulphuric. This salt is more soluble than the sulphate. Preparation. Tinctura Quininae — 1 grain in 1 fluid drachm of tincture of orange. Doses — Horses, §i. to |ii. ; dogs, Jss. to jii. ACTIONS OF CINCHONA AND QUININE. The actions and uses of cinchona resemble those of their most important active principle, quinine, so that we shall describe them together. (1) IMMEDIATE LOCAL ACTION. Externally quinine and its salts possess antiseptic and disinfectant properties, and are capable of arresting some forms of fermentation and decomposition. Internally. — In the mouth, stomach, and intestines, quinine acts as a powerful bitter, in a similar manner to that described under calumba (p. 452). The stomachic effect is obtained from small doses, and is distinct from the specific effect to be presently described. In small doses it improves appetite and digestion, stimulates the heart and circulation, and its continued use produces general tonic effects. In large doses quinine tends to interfere with digestion. In the stomach quinine and its salts are converted into the chloride, which is soluble and diffusible, and readily enters the blood. (2) ACTION IN THE BLOOD. Quinine is found in the blood very shortly after its administration, and exerts several important effects therein when given in full doses. Digitized by Microsoft® QUININE 507 1. It causes enlargement of the individual red cor- puscles. 2. It binds the oxygen more firmly to the heemoglobin, so that oxygenation is less active. 3. It diminishes the number, contractility, and move- ments of the vfhite corpuscles, and thus checks diapedesis. If blood be freshly drawn from the vessels it is ascer- tained that — - 4. Quinine retards theformation of acid, which naturally occurs in blood removed from the vessels. 5. It reduces the ozonizing power of blood, e.g., on guaiacum and turpentine. The total effects produced on the blood are : (a) Interference with oxygenation by lessening the amount of oxygen given up by the red corpuscles to oxi- dizable bodies. (b) Interference with the functions of the white cor- puscles. (3) SPECIFIC ACTION. Quinine quickly enters the tissues without decomposi- tion, but is not completely excreted for a long period, especially in febrile conditions of the system. The maximum effect of full doses is produced in about five hours, so that if the specific effect is desired, it is neces- sary to administer a single large dose, and to follow it up with smaller doses, as small amounts given over a length of time do not sufficiently accumulate. We do not observe the nervous phenomena in our patients which are produced in man by a full dose of quinine. Certain important specific effects, however, occur, to which we shall briefly refer : 1. Quinine in the healthy subject lowers the body tem- perature only very moderately, but in a high febrile con- dition the lowering of temperature is very marked. Digitized by Microsoft® 508 VETERINARY THERAPEUTICS 2. Quinine reduces the amount of nitrogenous excre- tions, i.e., the urea and uric acid. The amount of carbonic acid is also believed to be reduced in amount, both in health and in febrile cases. 3. Quinine, therefore, reduces the metaholism of the body in a marked degree, and experiments have demon- strated that it possesses some influence over living cellular protoplasm, which renders the latter less liable to incor- porate oxygen, and more resistant of metabolic change. It is rational, then, to conclude that the effect of quinine in the system is to check metabolism by inter- fering with the oxidation of protoplasm generally ; it also interferes with oxygenation and with the associated action of ferments. In febrile cases the fall of temperature produced by quinine is due to diminished production of heat, and not to increased loss of heat. This effect is produced through the tissues, and not through the heat-regulating centre. It is probable that the fermentative processes produced by certain organisms, which may be the cause of fevers, are controlled by quinine, this being another factor in its power of reducing abnormal temperature. In small doses quinine accelerates the heart and raises blood-pressure, but in full doses it diminishes the force and frequency of systole, strengthens diastole, and lowers blood-pressure ; these effects depend on a direct action on the cardiac ganglia and muscle, also on the vessel- walls and vaso-motor centre. In dogs, toxic doses cause death by respiratory and cardiac failure. (4) EBMOTE LOCAL ACTION. Quinine is chiefly excreted in the urine as the amor- phous alkaloid, and acts as a slight diuretic. It is also Digitized by Microsoft® QUININE 509 believed to be removed by the skin, and to diminish per- spiration. Medicinal Uses. — As a hitter stomachic aiid tonic, quinine is prescribed extensively in cases of atonic indigestion in horses, and is of great benefit given in doses of 20 to 30 grains, combined with small amounts of dilute hydrochloric acid and tincture of nux vomica. In convalescence from debilitating diseases, quinine is combined with a non-irritating preparation of iron, such as the liq. ferri dialysatus, the combination improving appetite, and acting as a general tonic to the system. In canine distemper it is a very valuable agent, and should be prescribed in small doses, frequently repeated, its effect on micro-organisms probably accounting for its beneficial action in this affection. As an antipyretic it is one of the most useful agents which we possess. In cases of influenza, acute pneu- monia, and acute rheumatism, quinine is invaluable when the temperature ranges high. It should be given in a dose of half an ounce at first, and followed at intervals of two hours with doses of two drachms, until the tem- perature falls. If much debility be present, it is of advantage to administer stimulants at the same time, so as to over- come any depressing effects which might be produced by the drug. "When the temperature is reduced, quinine may be continued in small doses with benefit. In such cases we believe that, in addition to its power of reducing excessive temperature, quinine produces valuable results by its action as an internal antiseptic, and by its influence on micro-organisms. It has been employed with success by Veterinary Cap- tain Burke, A.V.D., in cases of malarial and other fevers affecting horses and cattle in India [Veterinariaji, October, 1877). Digitized by Microsoft® 510 VETERINARY THERAPEUTICS Cinchonine and other alkaloids and products of cin- chona may be employed as substitutes for quinine, their actions being similar. Cinchonine is J to J as powerful as quinine. Cinchona bark contains only a small percentage of alkaloids, and hence is a bulky agent to administer. It contains a quantity of tannin, and may be prescribed in combination with iron in cases of relaxed conditions of the bowels, as a hitter stomachic and tonic astringent. In canine practice for similar purposes the compound tincture may be employed. Acidum Salicylicum— Salicylic Acid. Prepared by passing carbonic acid into a mixture of carbolic acid and caustic soda at a high temperature, and decomposing the salicylate of sodium with an acid and subsequent purification. Or prepared naturally from natural salicylates, such as the oils of winter-green, sweet birch, etc. Salicylic acid is very insoluble in water, readily in alcohol and in ammonium acetate. Incom;patihles. — Spirit of nitrous ether, iron salts. Doses. — Horses and cattle, 3ii. to 3iv. ; sheep, 3ss. to 3i. ; dogs, grs. iii. to grs. xv. Preparation. Sodii Salicylas — Salicylate of Sodium. Prepared by the action of salicylic acid on carbonate of sodium or on caustic soda. Eeadily soluble in water, but slightly in alcohol. Doses. — Horses and cattle, 3ii. to ^i. ; sheep, 3ss. to 3i. ; dogs, grs. X. to grs. xxx. Salicin. A glucoside obtained from the bark of Salix alba, and other species of Salix and of Populus. Doses. — Horses, 3i. to 3iii. ; dogs, grs. iii. to grs. xv. Digitized by Microsoft® SALICYLIC ACID 511 ACTIONS OF SALICYLIC ACID AND SALICYLATE OF SODIUM. (1) IMMEDIATE LOCAL ACTION. Externally, salicylic acid is an antiseptic and diswi- fectant, scarcely inferior to carbolic acid, 1 part in 60 destroying developed bacteria. It also stimulates the local circulation. Salicylate of sodium has no antiseptic or disinfectant power unless combined with a mineral acid to liberate the salicylic acid. Internally. — In the stomach salicylic acid, unless in a moderate dose, well diluted, acts as a local irritant, causing nausea and vomiting in the dog. The sodium salt is far less irritant, and is preferred in canine practice. (2) ACTION IN THE BLOOD. Salicylic acid is rapidly absorbed, and exists in the blood as the salicylate of sodium. It is believed that the acid is again liberated, but positive evidence on this point, and also on the changes which the drug undergoes in the blood, is wanting. (3) SPECIFIC ACTION. The action of salicylic acid and its sodium salt on the tissues is identical, as the former is converted into the latter. Full doses cause in dogs nausea and vomiting, disturbed respiration, depression of the heart after primary excitation, relaxation of the vessels, and lower- ing of blood-pressure. According to Dr. Eutherford, salicylate of sodium is a powerful liver stimulant, but a very slight stimulant of the intestinal glands. Moderate doses act as cardiac stimulants, and increase the cutaneous Digitized by Microsoft® 512 VETERINARY THERAPEUTICS circulation ; the temperature may be slightly lowered, although nitrogenous waste is said to be increased. Horses withstand the effects of large doses of salicylic acid to a remarkable extent, the only symptoms recorded being slight dyspepsia due to irritation of the alimentary mucous membrane. Dogs are more susceptible, and toxic doses of 75 grains, administered hypodermically, are reported to have pro duced dyspnoea, vomiting, weakness of hind-quarters, and convulsions followed by fatal paralysis. The most important action of salicylates is the power which they possess of reducing high temperature in febrile cases. This effect is believed to depend on some in-' fluence which they exert on the pathological cause of pyrexia, probably by acting on micro-organisms in a manner not yet understood. (4) EEMOTB LOCAL ACTION. Salicylic acid is slowly excreted in the urine, sweat, bile, and mucous secretions generally, chiefly as sali- cylates or the free acid, partly as salicyluric acid. On the kidneys and urinary passages, it acts as a stimulant and disinfectant, and increases the acidity of the urine. In large doses it may irritate the kidneys, so as to cause albuminuria, and even hematuria. Medicinal Uses. — In febrile conditions, with excessive high temperature, salicylate of sodium is recommended, such as in cases of influenza, pneumonia, etc. It is stated to be more rapid in its actions than quinine, less lasting in its effects, and more depressant to the circula- tion ; but in our experience quinine gives far more reliable results. In acute rheumatism, in all patients, the salicylate of sodium is regarded by many practitioners as a specific in Digitized by Microsoft® SALICYLIC ACTD—THIOFORM 513 reducing temperature, relieving pain, lessening the swell- ing and other local symptoms, and shortening the duration of the disease. In many instances, however, favourable effects have not resulted from the employ- ment of this drug, probably because the doses prescribed have not been sufficiently large. It is of no value in cases of chronic rheumatism. ■ In prescribing salicylic acid or its sodium salt, the doses should be repeated at intervals of two hours, and may with advantage be combined with the bicarbonate of potassium in full doses. When the pyrexia declines the dose of the salicylate should be gradually reduced, so as to avoid the danger of relapses occurring, which are very common in acute rheumatism. The sodium salt is preferred to the acid itself, as it is soluble, and less likely to derange digestion. Salicin is stated to be less powerful in its action than the sali- cylates, but to be better sustained, and to cause less cardiac and vascular depression. Salicylate of sodium is recommended in the treatment of chronic inflammatory affections of the bladder with foul alkaline urine and phosphatic deposits. Externally, salicylic acid is extensively used as a surgical dressing, in the form of cotton-wool or lint im- pregnated with the drug by the aid of glycerine. Thioform. A basic bismuth salt of dithio-salioylic acid; is pre- pared by mixing solutions of a soluble bismuth salt and dithio-salicylate of sodium. Actions and Uses. — Thioform has been suggested as a substitute for iodoform, and is highly recommended by Professor Hoffman as a surgical dressing. The 33 Digitized by Microsoft® 514 VETERINARY THERAPEUTICS following are the advantages which it possesses over iodoform : (1) It has greater antiseptic strength. (2) It is free from toxic properties and from odour. (3) It has a marked desiccative action. (4) It can be finely powdered, and is not hygroscopic, and retains its extreme fineness and consistence. It has been employed with success in the treatment of affec- tions of the stomach and intestines accompanied with fermentation, haemorrhagic diarrhcea, loss of appetite, emaciation, and general debility. In one case of chronic catarrh of the stomach and intestines in a dog, with a history of emaciation and frequent stools mixed with blood, reported at the Wiesbaden clinic, thioform was administered in large doses ; at first 2 drachms daily, together with milk diet. On the second day the haemorrhagic diarrhoea entirely ceased, and the appetite returned, so that more solid food was soon given, and in five weeks the animal had perfectly recovered. In this case opiates and subsali- cylate of bismuth had been previously prescribed without any success. As an antiseptic dressing for wounds thioform is an excellent agent ; it does not form a hard covering on the wound beneath which the secretions are apt to collect, but produces a supple protective layer which absorbs the wound serum and allows it to pass away ; it has also a non-irritant desiccative action on wounds and ulcers, and compared with iodoform it far surpasses it in healing quaUties. Professor Hoffman recommends to dust a thin layer of thioform on the wound, previously cleansed and dried. In wounds of the eyes and eyelids, also in conjunctivitis and keratitis, thioform- acts as an excellent antiseptic Digitized by Microsoft® OLIVE OIL 515 dressing. It can be applied by means of a diffuser, and we have seen the best results from its employment in such cases. The powder is extremely fine, does not irritate, and tends to promote rapid healing. The only drawback to the general employment of thioform in veterinary practice is its high price at present. CHAPTBE XVIII. THE VEGETABLE KINGDOM— Coreiinwed Oleum Olivae — Olive Oil. The oil expressed from the ripe fruit of Olea Europea. Actions and Uses. — Olive oil is laxative and emollient. It is given internally in cases of irritant poisoning ; it antagonizes the action of alkalies by forming soaps, and retards solution and absorption of arsenic. It forms a useful laxative enema for intestinal obstruction in the dog. Externally olive oil is extensively employed as a basis for liniments. Made into an emulsion with carbonate of potash and water, it forms an excellent application for softening the scales on parts which have been fired or blistered. Sapo Durus — Hard Soap, Sodium Oleate. Made with olive oil and soda. Sapo Mollis — Soft Soap, Potassium Oleate. Made with olive oil and potash. Preparation. Linimentum Saponis — Soap Liniment — Sapo durus, 16 ; camphor, 8 ; oil of rosemary, 3 ; spirit, 128 ; water, 32. Actions and Uses. — Soaps are in familiar use for the purposes of cleansing the skin, etc., and for removing the Digitized by Microsoft® 516 VETERINARY THERAPEUTICS scales in chronic skin diseases. They also form service- able additions to laxative enemas. The soap liniment is employed as a stimulating appli- cation, and also as a basis for other liniments. Clycerinum — Glycbeinb. A sweet principle obtained by reaction of fats and fixed oils with aqueous fluids, and containing a small percent- age of water. Actions and Uses. — Externally glycerine is slightly stimulant and antiseptic, and diluted it is demulcent and emollient. It is largely used as a constituent of lotions where a desiccant effect is desirable, in addition to an emollient action. Glycerine possesses marked powers as a solvent for fixed alkalies, alkaloids, and their salts. It is readily absorbed by the unbroken skin, and will carry into the system alkaloids or other active substances ; thus, when combined with belladonna and applied to the skin, the atropine will become absorbed. In pharmacy glycerine is combined with substances such as carbolic acid, tannic acid, boric acid, etc., forming an excellent vehicle for these agents. It is sometimes prescribed in mixtures containing iron, to disguise the taste of the latter. As an astringent, emollient application for eases of micd fever, cracked heels, and grease in horses, equal parts of glycerine and liquor plumbi diacet. are combined. As a laxative enema glycerine has been highly recom- mended, in amounts of half an ounce to an ounce for horses, either pure or diluted with one-third part of water. For dogs half a drachm to a drachm may be administered. The method adopted is to inject the agent with a com- mon wound syringe having a bulbous extremity. Digitized by Microsoft® TREA CLE— TEA GA CA NTH— GUM A CA CIA 517 According to Joly {La Presse VMrinaire, March, 1888), glycerine causes hypersemia and irritation of the mucous membrane and muscular coat of the rectum, and rapidly excites defsecation. We have not observed these effects to occur in the horse, after the use of glycerine enemata. In the dog, however, glycerine often exerts beneficial effect in cases of intestinal obstruction. In the form of suppositories glycerine is also very useful in similar cases. Theriaca— Tebaclb . The uncrystallized residue of the refining of sugar. Actions and Uses. — Treacle is demulcent, nutritive, and slightly laxative. It is combined with saHne purgatives for cattle, increasing their action, preventing nausea, and disguising the bitter taste, and may be given in doses of one pound. Treacle is employed in pharmacy as a con- venient excipient for ball masses, etc. Tragacantha — Teagacanth. A gummy exudation obtained from the stem of Astra- galus gummifer. Preparation. Mucilage Tragacanthse — 1 in 80 of water, with the aid of rectified spirit. Acaciae Cummi — Gum Acacia. A gummy exudation from the stem and branches of Acacia Senegal. Preparation. Mucilage Acaciae — Gum, 4 ; water, 6. Actions and Uses. — Both tragacanth and gum acacia are demulcents. They are chiefly used as vehicles for Digitized by Microsoft® 518 VETERINARY THERAPEUTICS heavy powders, such as bismuth ; also in the form of emulsions to prevent the irritating effects of certain drugs, such as chloral hydrate, in the mouth and throat. Clycyrrhizae Radix — Liquoeicb Eoot. The root, fresh and dried, of Glycyrrhiza glabra. Preparation. Extractum Glycyrrhizse — Aqueous. Actions and Uses. — Liquorice is a demulcent, and in- creases the flow of saliva and mucus when placed between the molar teeth. It is chiefly used as a basis for pre- paring electuaries, and is believed to allay irritation of the respiratory passages. Lini Semina — Linseed. The dried ripe seeds of Linum usitatissimum, flax. Preparation. Farini Lini — Linseed Meal — linseed reduced to powder. Actions and Uses. — Externally linseed meal is exten- sively employed in the form of poultices to convey heat and moisture to parts, and thus affect the nerves, circula- tion, and nutrition generally. Internally, in the form of linseed tea (made with about one part of steeped seeds to fifteen or twenty parts of boiling water, and infused for two hours), it forms a useful demulcent drink for horses and cattle in irritable condi- tions of the throat, ahmentary canal, kidneys and bladder, and is believed to have a remote local effect on the bronchi and urinary passages. In febrile cases it also acts as a valuable nutrient, and patients should be encouraged to partake of it ; it may Digitized by Microsoft® PEARL BARLEY— WHEATEN FLOUR— STARCH 519 be also allowed in the form of well-boiled gruel, or mixed with bran mashes. Linseed and linseed cakes are familiarly known as valuable feeding stuffs for cattle and sheep, and in re- stricted amount for horses. Hordeum Decorticatum— Peael Barley. The dried seed of Hordeum distichon divested of its integuments. Preparation. Decoctum Hordei — Barley Water — 1 boiled in 15 of water. Actions and Uses. — Barley water is nutritive and de- mulcent, and is chiefly employed in eases of irritable conditions of the bladder and urinary passages, the animal being allowed to drink it at pleasure. Farina Tritici — Wheaten Ploue. The grain of wheat (Triticum sativum) ground and sifted. Chiefly used in the form of wheaten flour gruel in cases of diarrhoea, superpurgation, etc. Amylum — Staech. Procured from the grains of wheat, maize, and rice. Is used in the form of starch mucilage, in cases of diarrhoea, dysentery, etc., being demulcent and emollient. It is an antidote for excessive doses of iodine. Externally starch is protective and absorbent. It is also employed in the form of paste to stiffen bandages for surgical purposes. Althaeae Radix — Maesh Mallow. The root of Althaea officinalis. Actions and Uses. — Marsh mallow contains a large amount of mucilage. When digested with boiling water Digitized by Microsoft® 520 VETERINARY THERAPEOTICS the mucilage is extracted and made into an ointment, which is a valuable emollient and demulcent application in cases of mammitis or garget. This ointment,- com- bined with belladonna and glycerine, and applied to the udder with a moderate amount of friction, is an excellent application in cases where the udder is greatly inflamed and painful. Chaulmugra Oil. Obtained from the seeds of Gynocardia odorata. Con- tains about 12 per cent, of an active principle, gynocardic acid. Actions and Uses. — Chaulmugra oil has been employed in human practice in cases of eczema and chronic skin affections. It is also recommended in the treatment of rheumatism, being given internally as well as applied locally. We are not able to produce any evidence of its employment in veterinary practice. It might prove useful in cases of obstinate eczema in dogs in the form of oint- ment containing 15 to 25 grains of gynocardic acid to the ounce of vaseline. Digitized by Microsoft® LANOLINE— PREPARED LARD 521 CHAPTBE XIX. GROUP II.— THE ANIMAL KINGDOM. Adeps Lanae Hydrosus— ' Lanoline.' Prepared from Adeps lanae or wool fat, the purified cholesterin fat of sheep's wool, by melting seven parts of the wool fat wifih three of distilled water in a warm mortar, and stirring in the water gradually and thoroughly. Actions and Uses. — Lanoline differs from ordinary fats by containing crystals of cholesterine instead of glycerine. It is not decomposed by boiling with alkaline solutions ; that is, it does not form soap, and it absorbs water readily. Lanoline can be rubbed into the skin with great ease, and has remarkable penetrating and absorptive powers; it is devoid of irritating effects. It forms the best basis for ointments of all kinds, especially those employed for affections of the skin, and also those for the purposes of counter-irritation. The ointments of cantharides and of biniodide of mercury, prepared with lanoline as a basis, produce a far better effect than when the basis is of .lard or vaseline. It is advisable to mix a small amount of vaseline when preparing the ointments, as lanoline alone is apt to become of too firm a consistence. A crude form of lano- line forms an excellent dressing for weak and brittle feet in horses. Adeps Preparatus— Pbepaeed Laed. The purified fat of the hog, Sus scrofa. Preparation. Adeps Benzoatus — Prepared lard, 50; benzoin, 1. Actions and Uses. — Lard is a simple emollient. It is frequently employed as a basis for ointments ; but, in Digitized by Microsoft® 522 VETERINARY THERAPEUTICS consequence of its tendency to become rancid, vaseline is generally preferred. The benzoated lard is not affected by keeping. Cetaceum — Speemaceti. Obtained from the head of the sperm whale. This is an emollient, and is also employed in pharmacy. Celatinum — Gelatine. Obtained from gelatigenous animal tissues ; is chiefly employed for coating balls, pills, etc. Oleum Morrhuaa — God-livee Oil. The oil obtained from the fresh liver of the codfish, Gadus morrhua. Contains 5 per cent, of free fatty acids. Doses. — Horses, gii. to gviii.. ; cattle, Jv. to ^x. ; dogs, 5i. to 5iv. Actions and Uses. — Cod-liver oil is nutrient, tonic, and alterative. It is more easily digested than other oils, from the amount of free acid contained in it, which facilitates saponification, emulsion, and absorption. It increases the richness of the chyle, improves the quality of the blood, especially as regards the corpuscles, and is thus a hmmatinic. It is a nutritive of the first importance, and is not only oxidized in the tissues, but spares the meta- bolism of the nitrogenous elements. It may be prescribed with benefit in cases of general debility in all animals, and should be given in the minimum doses at first, so as to avoid interfering with digestion, and it is of advantage to combine an aromatic oil. In dogs it is a very useful agent, in convalescence from distemper, and in young animals not thriving, also in the various cases of nervous affections. It is contra-indicated in diarrhoea, in haemoptysis, and Digitized by Microsoft® HONEY—CANTBARWES 523 in febrile conditions, also in irritable conditions of the Btomach. In cases where the oil does not agree, it is of advantage to prescribe alkaline stomachics before feeding, and the oil afterwards. Mel — Honey. A saccharine secretion deposited in the honeycomb by Apis mellifica, the hive bee. Actions and Uses. — Honey increases the secretions of the mouth and throat, acts as a demulcent, relieving dryness, pain, cough, and difficulty in swallowing. Its chief use is in the form of gargles in cases of glossitis, irritation of the mouth and throat, stomatitis, aphtha, etc., and for such purposes it is combined with chlorate of potash or borax. Cantharis — Canthaeides. The Cantharis vesicatoria, dried, also termed Spanish fly or beetle. Collected chiefly in Hungary. Contains ■4 to 1 per cent, of an active principle, cantharidin, pro- bably an acid, which is volatile, soluble in glacial acetic acid, ether, chloroform, alcohol and oils, and is a power- ful irritant. Preparations. Tinctura Cantharides — 1 in 80 of proof spirit. Doses. — Horses, 51. to 5iv. ; dogs, ^Jv. to iTLx. Unguentum Cantharidis — 1 to 8. (See Appendix, p. 546.) Should not be heated beyond 200° Fahr. in preparation, as the active principle is volatile. ACTIONS AND USES OP CANTHAEIDES. (1) IMMEDIATE LOCAL ACTION. Cantharides, applied to the skin, acts as a rubefacient and vesicant. Its effects differ from those of mustard in being much less rapid, but of a more severe degree. Digitized by Microsoft® 524 VETERINARY THERAPEUTICS Applied in the form of a properly prepared ointment, it causes, generally between three and twelve hours, the formation of large vesicles, which after a variable time burst, and discharge a yellow serous fluid which dries into scurfy cicatrices. If too freely used, it may cause excessive inflammation of the deeper layers of the skin, suppuration, and perhaps sloughing, with injury to- the hair bulbs, and a permanent blemish as the result. If applied to a large surface, the cantharidin may become absorbed, and produce effects presently to be described.. Internally cantharides, unless freely diluted, acts as an irritant to the mouth, throat, and stomach, and in toxic doses causes gastro-enteritis, strangury, andhsema- turia. Cantharidin enters the blood both from surfaces too extensively blistered and from the stomach, and flnds its way into all the organs, from which it is slowly eliminated. It disturbs the heart, respiration, and nervous system, causing irritability, quickened pulse, and injected mucous membranes. Cantharidin is slowly excreted by the kidneys, appear- ing in the urine, which conveys it to the bladder and genital organs. In small doses it causes diuresis and frequent desire for micturition, and in some cases is believed to act as an aphrodisiac — i.e., stimulates the sexual appetite. In full doses cantharides produces nephritis, with scanty bloody urine, or even suppression ; the penis becomes swollen, frequent erections occur, and in females the uterus may become congested. Antidotes. — In cases where cantharidin has been absorbed, and produces irritation of the urinary passages and strangury, a few doses of tincture of opium with bicarbonate of soda should be administered in muci- Digitized by Microsoft® ■ CANTRARIDES 525 laginous fluids, and the animal allowed cold linseed tea to drink. The blistered part should be washed imme- diately with warm water and a dilute alkali, and an emulsion composed of. olive oil, carbonate of potash, and water applied. It is a mistake to apply oil alone, as it tends to render the cantharidin more soluble. In cases where applications of cantharides produce excessive swellings of the limbs, with a tendency to sup- puration and sloughing of the skin (and let it be remem- bered that such may occur, no matter how carefully applied), apply fomentations, astringent lotions, and give gentle exercise as soon as the pain subsides. If the swellings involve the sheath and the under surface of the abdomen. Professor Williams recommends the parts to be punctured, so as to allow the escape of the contained fluid. Medicinal Uses. — Small doses of cantharides, such as 5 grains for the horse, are sometimes prescribed in cases of nasal gleet in combination with mineral tonics, but other agents are far safer and more effectual. Externally, cantharides is extensively used as a vesi- cant in the form of the ung. cantharidis, and may be employed for all the purposes of a counter-irritant (see p. 199). Where active effects are required it is advisable to combine equal parts of the ung. cantharidis with the ung. hyd. biniodidi. If properly prepared and carefully applied, cantharides does not as a rule cause any blemish, and in preparing the ointment it is necessary to heat the vehicle to about 200° Fahr., so as to dissolve the cantha- ridin, the usual strength of the application being 1 to 8 or 1 to 12. , It is also necessary to tie the horse's head to the rack after the blister is applied for forty-eight hours, in order to prevent him biting the part, or licking it with his lips or Digitized by Microsoft® 526 VETERINARY THERAPEUTICS tongue, which would cause a blemish, and also blister the mouth, etc. Some practitioners do not observe these precautions, but leave the animal loose, and they state that no un- toward effects occur. However, the risk of injury from the teeth is too great, and the safest plan is to adopt precautions to avoid it. If the blistered part is within reach of the tail, the latter should be tied up so as to prevent the blister being carried to the sheath, thighs, or mammary gland. Weak preparations of cantharides are believed to stimulate the growth of hair, and hence are recommended as a local application in cases where the hair-roots are weak. Contra-Indications. — Cantharides should not be em- ployed as a counter-irritant in patients suffering from affections of the kidneys, or in irritable conditions of the geni to-urinary passages. It should also be avoided in cases characterized by debility, and in weakly, exhausted subjects. In young animals it must be used with great caution, and in dogs only mild preparations should be employed, taking care that they do not lick the part. Counter-irritants of all kinds should be avoided when a part is in an already inflamed or irritable state, and measures should be adopted to reduce this condition before a blister is applied. Precautions to be observed in Blistering. (1) Not more than two legs should be blistered at one time, and three weeks should elapse before the others are blistered, and between each application. (2) If the effects of a blister are not sufi&ciently apparent in about thirty hours after application, a little Digitized by Microsoft® CANTHARIDES. 527 more may be applied ; but great discretion is necessary to avoid excessive action. (3) The blistered part should not be kept in too soft a condition, and the use of oil, etc., should be interdicted; the best application is an emulsion of carbonate of potash, oil and water (see p. 648). (4) In applying blisters to parts which have been fired, discretion is necessary ; and if the firing has been severe the blister should be mild. In well-bred horses with fine skins severe blisters should not be used. (5) In applying blisters it is important to avoid the flexures of joints, such as the posterior portion of the knee, the anterior portion of the hock, and the hollow of the pastern, as fissures may be produced in these parts which are difficult to heal. (6) In very hot weather extensive and severe blisters should not be employed. Digitized by Microsoft® APPENDIX VETERINARY PHARMACY, INCLUDING THE ABT OF PEESCEIBING AND DISPENSING, WITH HINTS ON THE ADMINISTRATION OF MEDICINES ; ALSO EXAMPLES OF PBESCEIPTIONS. VBTEEINAEY PHARMACY. Pharmacy is the art of making the preparations indicated or ordered by the therapeutist, and includes the dispensing of prescriptions. The details of pharmacy and dispensing must be studied practically , and it is essential that the student should spend a proper period of his time in dispensing prescriptions, and thus become familiar with the appearance and doses of the various drugs, so as to be able to obtain a definite knowledge of the subject, as he will find it impossible to fix them in his memory by endeavouring to study from books alone. Veterinary pharmacy in the present day differs in a marked degree from that of former times. We are not now compelled to prepare our own drugs, and are saved the labour and time of making up tinctures, etc., and also boluses, pills, etc., as there are reliable wholesale chemists and druggists who now under- take this portion of the work, and perform it in a manner, and oa terms, which no practitioner could manage to accomplish. For example, boluses, according to any formula required, are now prepared in an excellent manner, and covered with an airtight but soluble material, thus ensuring rapidity of action, non-impairment of keeping properties, and facility of adminis- tration. We must especially mention in this respect the dura- plastic balls prepared by Messrs. Wyleys and Co., of Coventry. Digitized by Microsoft® APPENDIX 529 To the student a large saving of time will be afforded, as instead of now burdening his mind with an endless number of methods of preparation, impurities, etc., he will be enabled to devote his energies to the actions and uses of the medicinal agents. In canine practice, too, a wonderful improvement has been made in the preparation of pills covered with gelatine, etc., easily administered, and readily soluble. While we are averse to the custom of prescribing similar formulas for cases of the same disease, and would prefer to treat individual cases on their merits, still, every practitioner has favourite combinations which he has found successful in treat- ment, and these he will continue to employ ; besides, we have to consider the great saving of time to the busy professional man, to have the formulae, which he is in the habit of using, dis- pensed, ready for use, in a reliable and neat manner. The veterinary pharmacy should be kept in an orderly condition, as nothing looks so slovenly as want of attention in this respect. All stock bottles should be neatly labelled ; this can be cheaply and effectually done by having labels printed with black lettering on a yellow ground ; these can be sized and varnished, and look extremely well when mounted. All poisons should be kept apart in a special portion of the pharmacy shelves, and be marked with a distinguishing label to avoid any mistakes being made. Every practitioner should keep a prescription-book, in which are entered all prescriptions dispensed ; this, besides being valuable for reference, gives the student excellent opportunities of acquiring a proper knowledge of the art of prescribing and dispensing. In addition to these details, the student should make himself familiar with the administration of the different forms of preparations to the various patients. To be proficient in this he must learn to work himself, as no amount of theo- retical instruction will be of value in this respect ; and he will find it absolutely necessary in many cases, when in practice, to personally administer medicines to his patients, if he wishes to be sure of their effects being produced. In dispensing prescriptions the student should aim at neat- ness in all details. Powders should be thoroughly mixed and blended, and folded up in paper similar to that made use of by chemists ; they are then arranged in cardboard boxes in quantities of six or twelve, and a proper label affixed with directions for use. Mixtures should be thoroughly blended, and if this is not possible, directions should be affixed to shake the bottle before using. This is particularly necessary in the case of irritating fluids, such as oil of turpentine, ammonia, etc. Mixtures 34 Digitized by Microsoft® 530 VETERINARY THERAPEUTICS should be dispensed in proper bottles, and suitable labels with directions thereon affixed. Lotions, liniments, etc., should have special labels, so as to avoid the danger of mistakes occurring, as attendants on animals are often very careless in this respect. Physic bails, if sent out, should have cZear directions printed on the cardboard box containing them, with reference to the preparation of the horse and after-treatment. This is a very- important matter when we consider the carelessness or ignorance of many grooms in this respect ; while the veterinary surgeon w"ho supplies the medicine is apt to receive blame if any un- toward effects occur. Blisters should also have labels attached to them containing specific directions, so as to avoid mistakes in appljing them. In dispensing, the student should pay particular attention to accuracy, and also to the doses of the medicinal agents, as it is only by this means that he can remember facts of importance in connection with this subject. Veterinary medicines should be dispensed with similar care and attention to neatness as those sent out by chemists for the use of human beings. There is no excuse for the employment, of dirty bottles, newspaper coverings, carelessly-folded powders, and other evidences of slovenly methods, which we often observe" in connection with the veterinary pharmacy. The minute amount of extra trouble involved in paying attention to these little details is amply compensated for by the satisfaction given to clients, many of whom appreciate method and neatness in the preparation of medicinal agents for their animals as well as for themselves. A well-kept pharmacy saves an enormous amount of trouble, as it enables the practitioner to at once lay his hand on what- ever agent he requires. In addition to this, it serves to train the student to habits of accuracy and business methods, of vital importance to him in his future career. We usually find that a student who is accurate and neat in dispensing is equally in- terested and careful in the other details of routine work. WEIGHTS AND MEASURES, WITH SYMBOLS. lu 1864 the Apothecaries' Weight was abolished, and the following standard weights were adopted : Symbol. 1 grain (granum) ... ... ... gr. i. 1 ounce (MBcia) =437 '5 grains ... gi. 1 pound (iftriim) =16 ounces ... lb. i. The scruple g, a weight equivalent to 20 grains, was also abolished ; but great inconvenience was caused for want of some Digitized by Microsoft® mi. = 60 minims. f.3i. = 8 fluid drachms. f.S!. = 20 fluid ounces. O.i. = 2 pints. Qt.i. = 8 pints. C.i. APPENDIX 531 denomination between the grain and the ounce, so that a weight termed the drachm was retained (drachma — symbol 5i.) to signify 60 grains. This, however, does not represent the J part of an ounce, as in the fluid measures, for the standard ounce contains but 437'5 grains. Measures. Symbol. 1 minim (minimum) 1 fluid drachm (drachma) 1 fluid ounce (uncia) 1 pint (octarius) \ quart (quartiis) 1 gallon (congiiis) Relation op Measures to Weights. 1 minim = -f-^ grain of water. 1 fluid drachm =54|- grains ,, 1 fluid ounce = 1 ounce „ 1 pint =1J pounds „ 1 gallon =10 pounds „ Domestic Measures. A teaspoonful is equivalent to 1 fluid drachm. A dessertspoonful is equivalent to 2 fluid drachms. A tablespoonful is equivalent to half a fluid ounce. A wineglassful is equivalent to IJ to 2 fluid ounces. A tumblerful is equivalent to 10 to 12 fluid ounces. These measures, however, are only approximate, and cannot be relied on when accuracy is required. A popular method of ineasuriug certain medicines is by the ' drop,' but as this varies according to the density and viscidity of the fluid, it cannot be relied on, and a graduated measure glass should be employed. Metric System. The metrical or decimal system of weights and measures is official on the Continent of Europe. The gramme, which is taken as the imit of weight, is a cubic centimetre of water at 4° C. or 39-2° Fahr. 1 gramme =15'4323 (about 15-|) grains. 1 decigramme = '1 gramme =1'543 (about If) grains. 1 centigramme = "01 gramme ='15 (about x%) grain. 1 milligramme = "001 gramme = "015 (about -j^) grain. 1 ounce is equal to about 28J grammes. 1 pound is equal to about 453f grammes. Digitized by Microsoft® 532 VETERINARY THERAPEUTICS Meastjees. 1 litre = 1 pint, 15 ounces and 2 drachms. 1 decilitre = 3 ounces and 230| grains. 1 centilitre = 154J grains. 1 millilitre = about 16 J grains. PRESCRIBING A.ND PRESCRIPTION- WRITING. The subject of prescribing has been already noticed in Part I., p. 31, and also the component parts of the classical prescription alluded to at p. 46. We may here again repeat that a prescription should contain as few medicinal agents as possible, that the technical portion of it should be written in Latin, and the signature or directions for its use or employment should be in English. The names of drugs must always be written in fall wherever there may be the smallest chance of error occurring. Thus, abbreviations such as acid, hydroc. dil. should be avoided as being dangerous, as it might signify dilute hydrochloric acid or dilute hydrocyanic acid. Again, hyd. chlor. might signify calomel or corrosive sublimate, mistakes which would occasion very serious consequences. Such terms should be distinguished as acid, hydrochloric dil. and acid, hydrocyanic dil., also as hyd. mhchlorid. and hyd. perchlorid. ; indeed, in the majority of instances it is far safer to write hyd. suhchlorid. in its vernacular name, calomel. A prescription consists of five parts : (1 ) The superscription, consisting of a single sign, R, an abbre- viation for recipe, signifying ' take.' (2) The inscription, or body of the prescription, containing the names and quantities of the drugs ordered. The names of the drugs or preparations are in the genitive case, and should be legibly written in the proper Latin idiom. (3) The subscription, or directions to the dispenser, also written in Latin. (4) The signature, or directions for use, headed by the abbre- viation sig., or signa. After this are added (5) the name of the owner of the animal, with the sex and colour of the patient, the date, and the initials of the prescriber. Certain abbreviations are allowed, viz., m. (misce), signifying mix ; s. (signa) ; aa. (ava), of each ; ft. (fiat), make ; div, (divide) ; q.s. (quantum sufficit), a sufficiency ; ad, up to, the amount to ; c (cum), with ; ss. (semi), a half ; pulv. (pulvis), a powdtr; hoi. (bolus); lin. (linimentum), a liniment; ung. (ungnentum), an ointment ; mist, (mistura), a mixture ; haust. (haustus), a draught, etc. Digitized by Microsoft® APPENDIX 533 Constant practice will enable the student to become proiicient in the writing of prescriptions. He is advised to at first write the names of the drugs which he intends to employ, and then to fill in the doses. Students often have considerable difficulty in approximating the doses for mixtures, and it is hoped that the following explanation will materially assist them : The practitioner usually computes his doses according to domestic measures, such as a wineglassful, a tablespoonful, etc. The amount of a mixture is prescribed according to the require- ments of the case, in bottles of various sizes, usually pint and half-pint bottles for horses and cattle, and from 8 ounce to 4 ounce bottles for dogs. The dose of mixtures for horses is generally computed in quantities of wineglassfuls, and for dogs in do.ses of froai a tablespoonful to a teaspoonful. Now, in ordering a certain quantity of a mixture the pre- fcriber has first to ascertain the number of doses which the phial contains, and then to decide the amount of each drug to be given in every dose ; then by multiplying this by the number of doses contained in the phial he obtains the proper amount to prescribe, so that each wineglassful or tablespoonful, as the case may be, represents a sufficient dose of the medicinal agent. Example. 5i Tr. digitalis, 3x. Tr. ferri perchlor., gii.ss. Aqua ad O.i. F. m. Sig. Give two wineglassfuls twice a day in a pint of ale. The above, which is an example of a cardiac tonic for the horse, explains the method of approximating the doses. Thus, we are ordering a pint bottle of the mixture, and of this two wineglassfuls are to be given as a dose twice a day. Now, a pint bottle contains 20 ounces, and a wineglassful is equivalent to 2 ounces, so that it would contain ten wineglassfuls, or five doses of two wineglassfuls each. The dose of tr. digitalis for the horse is about 3ii. ; this multiplied by five gives the amount of the drug necessary for the pint bottle, viz., 5x. Again, the ordinary dose of the tr. ferri perchlor. is gss. ; this multiplied by five gives gii.ss., so that every two wineglassfuls of the above mixture represents gii. of tr. digitalis and gss. of tr. ferri perchlor. In canine practice we can work on similar lines, the amounts generally prescribed varying from a tablespoonful to a tea- spoonful, according to the size of the patient ; and the capacity of the phials may be from 8 ounces to 2 ounces, according to requirements. Digitized by Microsoft® 534 VETERINARY THERAPEUTICS Sig, Example. Quininae sulpb., grs. xl. Ac. sulph. dil., q.a. Tr. nucis vom., 5"- Syr. aurantii, oii. Aqua ad gviii. Give a tablespoonful twice a day. The above represents a nervine touic mixture for a fall-sized dog. The mixture contains 8 ounces, equivalent to sixteen doses of a tablespoonful each. In each dose we are giving about 2-^ grains of quininae sulpb .^ and about 8 minims of tr. nucis vom. The following table may be found useful to the student while dispensing or prescribing, as it will enable him to judge of the amount requisite to ensure a proper number of medicinal doses : Doses of Doses of Doses of Doses of Doses of wineglass- half-wine- tablespoon- dessert- teaspoon- fuls. glassfuls. fuls. spoonfuls. fuls. Phial. 1 pint = 10 = 20 = 40 = 80 = 160 4 pint = 5 = 10 = 20 = 40 = 80 8 oz. = 4 = 8 = 16 = 32 = 64 6 oz. = 3 = 6 = 12 = 24 = 48 4 oz. = 2 = 4 = . 8 = 16 = 32 2oz. = 1 = 2 = 4 = 8 = 16 Another table which may prove useful to the student in the pharmacy is one relating to the strength of solutions, such as in the preparation of the various antiseptic dressings and lotions. The following gives the proportion as regards the strength of preparations by parts as well as calculated by percentage, and also the number of grains to the ounce, and to the pint, to form solutions of specific strength. These are not strictly accurate, as they are calculated so as to avoid fractions ; but they will be found sufficiently so for practical work : Part. Parts. Grains. Grains. 1 to 1000 is = tV%= about J to f.5i.= 10 to O.i. 1 to 500 is = i%= ,, 1 to 5i.= 20 to O.i. 1 tn 100 i^. = 1%= „ 5 to 5i.=100 to O.i. Digitized by Microsoft® APPENDIX Part. Parts. Grains. Drachma. 1 to 80 is 1 to 50 is 1 to 40 is = li% = 2% = 24% = about 6 to gi. = „ 10 to §i.= „ 12 to gi. = 2 to O.i. 35 to O.i. 4 to O.i. Ounces. 1 to 20 is 1 to 10 is = 5% = 10% = )) 24 to gi. = 48 to gi.= Drachms. 1 to O.i. 2 to O.i. 1 to 5 is 1 to 2J is 1 to 2 is 1 to li is = 20% = 40% = 50% = 80% = I) >> If to gi. = 3i to gi. = 4 to gi. = 64 to gi. = 4 to O.i. 8 t. O.i. 10 to O.i. 16 to O.i. 535 HINTS ON THE METHODS OP ADMINISTRATION OF MEDICINES. To administer the difEerent forms in ivhich medicinal agents are prescribed requires tact, dexterity, and practice. We are fully aware that a large proportion of medicinal agents which we order, for horses especially, is either not administered at all, or the major portion of it is wasted by ignorant or careless attendants. These facts will often account for the want of success attributed to the use of certain medicinal agents in the treatment of disease, and as a rule it is only when we either administer the medicines ourselves, or see it properly done, than we can be sure of results. Balls are administered either with the hand alone or assisted by a balling-iron, when the animal has very sharp teeth, or has acquired a habit of working the jaws vigorously when the hand is introduced into the mouth. Some practitioners use a form of balling-gun which appears to work very well. In administering a ball, the most important point is to secure a proper hold of the animal's tongue, and to prevent the head being raised too high, by an assistant keeping his band on the nose. The ball is held between three fingers, and the hand, being brought together as much as possible, is passed rapidly along the roof of the mouth, the ball pushed gently into the region of the pharynx, and the hand quickly withdrawn. It may be necessary to keep the animal's head held up for a few minutes, if it does not swallow the bolus, or to allow it to take a few sups of water. In some horses it is very difficult to administer medicine in the solid form, as they acquire great dexterity in rejecting the bolus, and chew vigorously when the hand is introduced into the moiilh. Others persistently cough and reject the bolus, no matter how carefully administered. For the latter, medicines in the fluid form must be substituted. Digitized by Microsoft® 636 VETERINARY THERAPEUTICS The student should render himself proficient in the administra- tion of balls, and constant practice alone will enable him to accomplish this. The duraplastic horse balls prepared by Messrs. Wyleys and Co., Coventry, are easily administered, and are a vast improve- ment on the old-fashioned paper-covered article. Medicinal agents administered in the solid form take a con- siderable time to become soluble, and in a fit state for absorp- tion. Experiments have demonstrated this point, and also that there is little or no absorption from the stomach of the horse ; hence, if this organ is impacted with ingesta or distended with gas, and its walls in a semi-paralyzed condition, it is evident that drugs in the solid form will not produce any effect, as they will not pass beyond the stomach. Clinical experience furnishes sufiicient evidence of this fact, and in such cases drugs should be administered by hypodermic injection. In cattle, medicines in the solid form are seldom administered, as such would remain among the extensive contents of the rumen, and produce little or no effect. In dogs, medicines may be conveniently administered in the form of pills, which are now prepared in an excellent manner by wholesale chemists, coated with either gelatine or sugar. These are easily swallowed, and are prepared so that the contents are readily soluble. Drenches require to be carefully administered, so as to avoid the danger of any of the fluid passing into the larynx and trachea. The horse's head should not be held too high, and the tongue should be left perfectly free ; if any attempt be made to cough, the animal's head should be released immediately. The drench should be administered slowly, as by pouring too much at a time into the mouth there is danger if the animal coughs, and, besides, a large amount of the medicine is wasted. JDrenches should be administered out of a proper tin drenching-horn, as glass bottles are very dangerous if they happen to get broken between the animal's teeth. In cases of respiratory affections, with laryngitis or bronchitis, drenches should not be administered if possible, as from the irritable condition of the throat, etc., and the tendency to violent fits of coughing, the fluid may find its way into the trachea and bronchi, and give rise to mechanical bronchitis. In cases of this kind, medicines should be given in the patient's drinking- water, or in the form of an electuary placed between the molar teeth. In cattle, great care is necessary in administering medicines in the fluid form, and many accidents have occurred from the fluid entering the trachea and bronchi, due to carelessness in this respect. The drench should be administered slowly, care being Digitized by Microsoft® APPENDIX 537 taken not to have the animal's head held too high ; it should also be held in as straight a manner as possible. In cases of mllk-fever, in which swallowing is difficult or im- possible, no fluids should be given by the mouth, but should be directly introduced into the rumen by means of Toope's trocar and cannula, which is an invaluable instrument in such cases. In dogs, medicines in the fluid form are easily administered, it being of advantage to have the mixtures in as palatable a form as possible. The best plan is to pour the fluid slowly into the corner of the mouth, first distending the cheek with the finger so as to form a sort of pouch : the medicine is then readily swallowed without any inconvenience. Powders should not contain substances having a disagreeable or nauseous taste, as otherwise they will be refused by the patient. Properly prepared they are readily taken in the food, and are a most convenient method of administering medicines. As a rule, powders should not be mixed in a hot medium, but should first be incorporated with a portion of cold bran mash, and then mixed in the feed. Heat increases the smell and taste of medicinal substances. Medicines possessing little or no taste, such as saline substances, are readily taken when dissolved in the patient's drinking-water, the latter being left within reach so that it can be partaken of at pleasure. Electuaries are prepared in a semi-fluid condition, so that they can be easily placed between the patient's molar teeth when swallowing is difficult or impossible, such as in cases of acute laryngitis and in tetanus. They become dissolved in the secretions of the mouth, and are then slowly swallowed. Hypodermic and intratracheal injections are the most reli- able methods of introducing medicinal agents into the system. The proper doses are now prepared in the form of hypodermic pellets, which can be readily dissolved in a small amount of water when required for use. The loose skin of the neck or breast is the most convenient site for hypodermic injections, the most im- portant points in connection with which, are to have the syringe, needle, and fluid in an aseptic condition, and to avoid employing anything of an irritant nature in the solution. Neglect of these precautions is often the cause of abscesses occurring at the seat of injection. In intratracheal injections, one of the spaces between the rings of the trachea is selected, about midway along its course, the needle is inserted, and the fluid slowly forced in. Another method of administering medicines has of late years been growing in favour ; this consists in introducing the medi- cinal agent in the form of solution directly into the large intestine of the horse and the rumen of the cow by means of a narrow trocar and cannula, and an indiarubber syringe attached, Digitized by Microsoft® 538 VETERINARY THERAPEUTICS iavented by Mr. Toope. It has given moat satisfactory results in cases of flatulent colic in the horse, and tympanitic conditions of the rumen in the cow. It is also of great advantage in administering medicines in cases of milk-fever in cattle, when the power of swallowing is impaired or lost. It is necessary for the veterinary surgeon, especially in a country practice, to have a portable medicine chest in which he can carry the medicinal agents required in ordinary cases, as it is often difficult, if not impossible, to obtain medicines in country places, and many cases which he is called to, require immediate treatment. The medicine case should be made either of leather or wood, of a portable shape, and should contain stoppered bottles of sufficient strength of material. The following medicinal agents will be found of service : 1 8-oz. bottle of either tr, opii or chlorodyne. 1 ,, „ of spts. seth. nit. 1 4-oz. „ of spts. ammon. aromat. 1 „ „ of ol. tereb. 1 20-oz. „ of ol. lini. 1 4-oz. „ of aether sulph. 1 „ „ of creolin. 1 tube of hypodermic pellets of morphine. 'I balls of ext. ca,nnabis indica. 2 physic balls. 1 4-oz. bottle of glyoerinum belladonuae. 1 pot of vaseline. 1 oz. iodoform. J lb. antiseptic wool. 2 bandages. Wound syringe. 1 4-oz. bottle of liq. ferri perchlor. Small instrument case. Hypodermic syringe. Measure-glass. 1 purgative mixture for cattle. 2 drachms of croton oil. 1 tin drenching-horn. Winton's enema syringe. A case thus fitted will prove of inestimable value, because in many instances the practitioner is not informed of the nature of the case, especially when summoned by telegram, and his destination may be far away from any pharmaceutical chemist. Digitized by Microsoft® APPENDIX 539 PEBSCEIPTIONS. ■ FEBRIFUGES. Horses. I^ Liq. ammonii acet., §x. S^jts. aeth. nit., gvi. Aqua ad O.i. V, m. Sig. Give two wineglassf uls every four hours in half a pint of water. !^ Quininse sulph., 3x. Ac. sulphuric. dU., q.s. Aqua ad O.i. F. m. Siij. Give two winegla-sfula every three hours in two glasses of whisky and two glasses of warm water until the fever declines. In HyiiRrpyrexia. ]J Chlorodyni, 3i. Spts. seth. nit., gii. Liq. ammonii acet., gii. Aqua ad 5xv. F. m. S g. Give every three hours in three glasses of whisky. {Useful in the primary stages of influenza, when rigors are present.) ]^ Mag. sulph., gxii. Potass, nit., §i i. Div. in pulv. vi. Sig. Give one twice a day dissolved in the patient's drinking-water. Dogs. 5i Spts. seth. nit., §ii. Liq. ammonii acet., giii- Aqua ad gviii. , m. Sig. Give two teappoonfuls every three hours. For dog of larger size the dose may be increased in prop Ttion. Digitized by Microsoft® 540 VETERINARY THERAPEUTICS Febrifuges for Dogs — continued. I^ Quininae salph., 3i.s8. Ac. sulph. dil., q.s. Sodii hyposulph., 3'i- Aqua ad gvi. F. m. Sig. Give two teaspoonfuls three times a day. ( Useful in the primary stages of distemper. ) DIURETICS. Horses. 1^ Potass, acet., ^\i. Tr. digitalis, 5^. Spts. seth. nit., gv. Aqua ad O.i, P. 111. Sig. Give two wineglassfuls every four hours in half a pint of water. 3^ Tr. colchici, 5v. Spts. aeth. nit., gv. Liq. ammon. acet., §vi. Aqua ad O.i. I'\ in. Sig. Give two wineglassfuls every four hoard until the kidneys act. ( Useful in azoturia, loith scanty secretion of urine.) ]^ Fulv. resinffi, giii. Potass, nit., gii. Div. in pilv. vi. Sig. Give one twice a day in the food. Dogs. IJ Potass, acet., gss. Syr. scillse, gss. Tr. digitalis, 3i. Spts. Eeth. nit., gss. Aqua ad gvi. F. m. Sig. A tablespoonful three times a day. ( Useful in dropsy due to cardiac disease.) Digitized by Microsoft® APPENDIX 641 TONICS. Horses. ]J Liq. ferri dialysatus, §iii. Tr. quininse to., gx. Aqua ad O.i. F. m. Sig. Give two w ineglassfuls twice a day in half a pint of water. (Useful where a non-astringent preparation of iron is indicated.' ]J Tr. ferri perchlor. , giii. PotassEe eh lor., 5ii. Syrupi, q.s. Aqua ad O.i. F. m. Sig. Give two wineglassfuls every four houip. ( Usefod in purpura. ) 5i Ferri sulpli., 3vi. Mag. sulph., gv. Ac. sulph. dil., §ss. Tr. quassias, gv. Aqua ad O.i. F. m. Sig. Give two wineglassfuls twice a day in a pint df ale. ( Useful in debility, with a tendency to constipation. ) ]^ Ferri sulpb., Z^i. Pulv. gentian, gii. P. carui sem., gii. Dif. in pulv. vi. Sig. Give one twice a day in the food. Cattle. TJ Mag. sulph., gxii. Ferri sulph., gii. Pulv. gentian., giii. P. carui sem., giii. Div. in pulv. vi. Sig. Give one twice a day in the food, or dissolved in a pint of ale. Digitized by Microsoft® 542 VETERINARY THERAPEUTICS Tonics — continued. Dogs. ]J Tr. ferri perchlorid., gss. Tr. quaasiae, 5ii. Glycerini, gss. Aqua ad gvi. F. m. Sig. Give from t»o teaspoonfula to a tablespoonful (according to size of dog) twice a day. 1^ Quininse sulpti., grs. xxiv. Ac. sulph. dil., q.a. Syr. aurantii, §ii. Aqua ad 5vi. F. m. Sig. Give two teaspoonfals three times a day. ALTERATIVES. Horses. I^ Liq. arsenicalis, P.B., gii. Tr. gentian. CO., gv. Aqua ad O.i. E. ni. Sig. Give two wineglassfuls twice a day after feeding. ^ Sulphur, sub., gii. Potass, nit., §i.ss. Sodii bicarb., gii. P. carui sem., gii. Div. in pulv. vi. Sig. Give one twice a day in the food. GASTRIC TONICS. Horses. ]^ P. nucis vom., gss. Pulv. gentian., gii. Sodii bicarb., gii. P. carui sem., gii. Div. in pulv. vi. Sig. Give one t nice a day in the food, or dissolved in a pint of ale. Digitized by Microsoft® A PPENDIX 543 Gastric Tonics — continned. Dogs. ^ Tr. nucis vom., gas. Liq. arsenicalis, P.B., 3i- Tr. gentian, oo., gi. Syr. aurantii, gi. Aqua ad gvi. F. m. Sig. Give two teaapoonfuls three times a day after feeding. Increase the dose for large-sized dogs. CATHARTICS. Horses. ]J Aloes Barb., 3^. Ext. belladonnEe, 3ss. P. zingib., 5ii. Ft. bol. i. Sig. Physic ball. T^ Hyd. subchlorid., gi. Aloes Barb., 5^v. Ext. belladonnaa, 5ss. P. zingib., 5ii. Ft. bol. i. Sig. To act as purgative and oholagogue. ^ 01. tereb. rect., gi. 01. lini. O.i.ss. F. m. Sig. Oleaginous purgative. IJ Physostigminae salicylas, grs. i.ss. Pilooarpinae nitras, grs. iii. Aqua, q.s. M. Sig. To be given by hypodermic or intratracheal injection. ( Used in cases of impaction of the colon, with imralysis of its walls. ) Cattle. 1^ Mag. sulph., lb. i. P. zingib., gi. Theriacae, lb. i. Aqua ferv., O.iii. M. S'g. Give all at one dose, administering slowly. Digitized by Microsoft® 544 VETERINARY THERAPEUTICS Cathartics for Cattle — continncil. IJ 01. crotonis, 5i- Hyd. subchlorid., 5"- 01. lini, Qt. i. F. m. Sig. One dose. ( Useful in cases where a very active purgative is necessary.) Sogs. ^ 01. ricini, §8s. to §i. Spts. ffith. nit., 5ss- Syr. rhamni, 5ss. to gi. r. m. Sig. Purgative mixture. 1^ Ext. colocynth. co. , grs. iii. Pil. hydraigyri, gr. i. Ext. hyoscyamus, gr. i. Et. pil. i. Sig. Give one or two, according to the size of the dog. ASTRINGENTS. Horses. J}l, p. catechu, 5vi. Cretae prep., gii. P. camphorse, 5iii. P. zingib., S'. Div. in pulv. vi. Sig. Give one every four hours in a pint of flour grutl. ]Ji Chlorodyni, §ss. Tr. camphor, co., gi. Cretae prep. , gss. Aqua ad O.ss. F. m. Sig. Give in a pint of flour gruel. Foals. R Chlorodyni, 3i. Tr. rhei, gii. Cretse prep. , gss. Aqua ad giv. F. m. Sig. Give in haU a pint of flour gruel. Repeat in tvpo hours if necessary^ Digitized by Microsoft® APPENDIX 545 Astringents— continaerf. Cattle. ]^ P. ext. hasmatoxyli, gii. Cretae prep., gii. Aqua, q.s. m. Sig. Give in a pint and a half of flour gruel. DogF. 9 Chlorodyni, nixv. CretEe prep., grs. xx. Tr. gentian, oo., lUxx. Aqua ad gss. Sig. Give in a little starch and milk. Repeat in two hours if necessary. ANODYNES AND ANTISPASMODICS. Horse?. ^ Chlorodyni, gii. Spts. seth. liit., gii. 01. lini, O.i. F. m. Sig. Give at one dose. Kepeat in two hturs if necessary ( Useful in simple colic, ) 1^ MorphinEe hydrochlor., grs. x. Ac. hydrochlor. dil., q.s. Chloral hydras, gi. Mucilago acaciee, q.s. Aqua, O.i. F. m. Sig. One dose. ( Useful in cases where morphine produces an exciting effect.) ^ Ext. cannabis indica, gas. Ft. bol. i. Sig. One dose. Repeat in an hour if necessary. ( Useful in cases of violent or persistent abdominal pain. ) 35 Digitized by Microsoft® 546 VETERINARY THERAPEUTICS Anodynes and Antispasmodics — contimted. Dogs. 5; Tr. opii, mv. to inxx. Spts. «th. nit., ^m. Tr. zingib., nixx. Aqua, gss. Sig. One dose. Repeat in two hours if necessary. ANTI-TYMPANITICS. Horses. jt Creolin, gss. 01. tereb., ^i\. Spts. ammou. aromat., 5i*' Tr. asafoetidEe, gii. 01. lini, O.i.ss. F. m. Sig. One dose. ( Useful in flatulent colic.) Cattle. 'fy Creolin, gi. Ol. tereb., giv. Spts. ammon. arom., giv. Ol. lini, O.i.ss. F. m. Sig. One dose. (Useful in hoven.) GASTRIC SEDATIVES. Horses. ^ Glyoerini belladonnas, 3ii. Tr. opii, §i. Sodii bicarb., gss. Aqua ad O.i. F. m. Sig. One dose. Repeat every three hours. ( Useful in gastritis.) Digitized by Microsoft® A PPENDIX 547 Gastric Sedatives — conlimted. Cattle. I^ Glycerlni belladonnaa, §ss. Sodii bicarb,, gss. Aqua, O.i. F. m. Sig. One dose. Repeat every three hours. ( Useful in inflammation of the fourth stomach, after a few doses of raw linseed oil have been administered. ) Dogs. ]J Ac. hydrocyanic dil., tiii. to itliii. Bismuthi subnit., grs. v. to grs. xx. Mucilago acacise, q.s. F. ra. Sjg. One dose. Eepeat in an hour if necessary. {Usefid in gastrilin and obstinate vomiting.) ANTHELMINTICS. Horses. ^ 01. tereb., gii. Ext. filiois liq., 5ii- Liq. ferri dialysatus, gss. 01. lini, O.i. F. m. Sig. One dose. To be given fasting. Dogs. IJi Santonini, grs. iii. Pulv. areca, grs. xx. Ft. pulv. i. Si/. To be given in milk. For dogs of larger size this dose may be doubled. EXPECTORANTS AND RESPIRATORY SEDATIVES. Horses. ^ Pulv. camphorse, 3iii. Potass, chlor., gi.ss. P. fol. belladonnse, gi.ss. Pulv. anisi fruct., gii. Div. in pulv. vi. Sig. Give one twice a day in the food. ( Useful in simple coughs depending on catarrh. ) Digitized by Microsoft® 548 VETERINARY THERAPEUTICS Expectorants snd Respiratory Sedatives for Horses — continued. ^ P. fol. aconiti, 3vi. P. digitalis, 3iii- Arsenic, alb., grs. iv. P. anisi fruct,, ^!>. Div. in pulv. \i. Sig. Give one every night in the food. ( Useful in clironic cough.) 1^ Liq. arsenicalis, P.B., gii'. Tr. nucis vom., giii. Tr. camphor, ci) , giii- Aqua ad O.i. m. Sig. Give two wineglassfuls twice a day after feeding. (Useful in coughs depending ore gastric derangements.) Dogs. ]^ Tr. beiladonnse, g-s. Syr. scillae, gss. 'J'r. camphor. Co., gi. Aqua ad gvi. F. m. Si^. Give two teaspoonfuls three times a day. COUNTER-IRRITANTS. ]^ Pulv. cantharides, gxx. 01. tereb. rect., gxii. Acid, acetic, fort., gix. Mix for twenty-four hours, then add 2J lb. each of lanoline an vaseline, melted at a temperature of 200° Tahr., and stir well ti thoroughly mixed. Keep in an air-tight jar. Sig. : Ung. Cantharides Co. Fly b'ister. J^ Hyd. biniod., gii. Lanolini, gxii. Vaselini, giv. Ft. ung. Sig. : Ujig. Hyd. Biniod. {Useftdfor the treatment ofossific affections of joints, etc.) Digitized by Microsoft® APPENDIX 549 Counter-irritants— conimacd. ^i Hyd. biniod., giv. Potass, iod., giii. Aqua, 5ii. Dissolve, thea add — ^ Puly. cantharides, gviii. Spts. vini meth., §xxxiv. Digest for fourteen days, and after filtering add sufficient methylated spirit to make 40 oz. of clear fluid. ( Very strong blistering fluid, to be applied with a brush.) LINIMENTS. 9 01. tereb., gi. Liq. ammou. fort., gi. 01. olivEe, giv. Ft. lin. Sig. {As a counter-irritant for application to the throat, etc.) ]?; 01. tereb., gxvi. Camphorae, gi. Sapo mollis, gii. Aqua destil., gii. Mi.v the soap with the water, dissolve the camphor in the tur, entine, rub together till thoroughly mixed, add sufficient water to make a fluid emulfsion. Sig. : Lin. Tereb. Album. {As a stimulating liniment.) ]J Tr. arn'cse, giv. Tr. camphoFEe, giv. Liq. ammon. f., 3ii. Sapo mollis, gii. Aqua ad O.i. Ft. lin. Sig. : Lin. Gainph. c. Arnica. {Useful as a mild stimulating liniment.) 9 Tr. iodi, gii. Spts. picis, gii. Sapo mollis, gii. Ft. lin. Sig. Apply with a brush once a day. {Useful as an absorbent liniment in cases of capped hocks, wind- galls, etc.) Digitized by Microsoft® 550 VETERINARY THERAPEUTICS Liniments — continued. ^ lodi., gv. Potass, iod., ^ii. Glycerin], §i. Spts. rect., Qh. i. Ft. lin. Sig. : Linimentum lo H. {Useful as an application for enlarged glands and burscB.) ^ Potass, carb., 5ii" 01. olivffi, O.ss. Aqua, O.ss. Pt. lin. Sig. : Lin. Alha. White liniment. (For applying after hlisters.) ^ Liq. pltimbi diaoet., O.ss. 01. eucalyjti, 5'i. 01. olivae, O.ss. Ft. lin. Sig. Apply twice a day. {For mvd fever, cracked heels, grease, tic.) LOTIONS. Astringent. ]^ Plnmbi acefc., .^i. Zinci sulph., 5vi. Aqua ad O.i. Pt. lotio. Sig. : Lotio Alba. White lotion. Antiseptic. J^ Creolin, 3ii. Pyoktanin, grs. viii. Aqua, O.i. Ft. lotio. Sig. : Lotio Antiseptic. {Fur dressing uounds.) ]^ Hyd. zinci. cyanidi, grs. x. Acjvia, O.i. Ft. lotio. Digitized by Microsoft® APPENDIX 561 Lotions — continued. !^ Hyd. perohlorid., grs. xxxvi. Liquor ca'cis, O.i. Ft. lotio. Sig. : Lotio Hydrargyri Flava, Yellow wash. ( Useful in cases of collar and saddle galls, and ulcerated surfaces.) ^ Ac. boric, grs. iv. Aqua laurocerasi, g-s. Aqua destil., gss. Ft. lotio. Sig. Apply twice daily. {As a coUyrium in conjanctiviiis.) J^ Argenti uit., grs. iv. to grs. vi. Aqua destil., g'- Ft. lotio. Sig. Apply with a camel's-hair brush once daily. {As an applicalion for albugo and nebula.) ^ Atropinse sulph., grs. ii. to grs. iv. Aqua destil., gi. Ft. lotio. Sig. : Liq. Atropince Sulph. {As an application to keratitis, ophthalmia, etc.) OINTMENTS. ^ lodi, 51. Potass, iod., §ss. Lanolini, gviii. Ft. ung. Si^. : Ung. lodi. Absorbent ointment. ]J Sulphur sub., gi. l^lumbi acet., gss. Creolin, g>s. 01. eucalypti, gsp. Vaselini, giv. Lanolini, giv. Ft. ung. Sig. Apply twice daily. (/;i cases of grease, cracked heels, etc.) Digitized by Microsoft® 552 VETERINARY THERAPEUTICS Ointments — continued. ^ Sulphur sub., 5i. Potass, carb., gss, Lanolini, '§i\. Ft. ung. Sig. : Ung. S%dpho- Alkalinum. (Useful in cases of parasitic skin affect'ons in the dog.] 1^ lodoformi, gss. 01. eucalypti, 5ss. Vaselini, 5vii'. Ft. un?. Sig. : Ung. Antiseptic. ( Useful as an antiseptic ointment.) Digitized by Microsoft® INDEX. AoAoiA, 517 A. C. E. mixture, 357 Aoetaniliduiu, 379 Aoetum, 322 Acids, 308 Acidum aceticura, 321 arseniosum, 277 benzoioum, 473 boricum, 319 carbolioum, 369 chrom'cum, 321 citricum, 322 gallioum, 498 hydrochlorieum, 315 hydrocyanioum, 3G6 nitricnm, 313 nitro-liydrochlorioum, 318 pyro-gallioum, 500 salicylioum, 510 sulphuricum, 311 aromaticum, 312 sulphurosum, 306 tannicum, 498 tartaricum, 822 Accumulation, 43 Aconite, 385 Aconitina, 386 Aotifn of medicines, 25 Adeps, 521 Adeps lanee, 521 Adjuvants, 47 Administration of drugs, modes of, 33 Administration of medicines, hints on, 535 ^tlier, 354 Alcohol, 325 uses of, 331 Alkalies, 214 Alkaline earths, 28 Alkaloids, 212 Aloes, 484 precautions in prescribing, 485 Aloin, 484 Alteratives, 122 Althese radix, 519 Alum, 253 Alumen, 253 Aluminium, 253 Ammonia, preparations of, 226 Ammoniaoum gum, 476 Ammonium, salts of, 226 Amyl nitris, 362 Anaesthetics, 161, 336 local, 158 Anhydrotics, 187 Anise, 461 Anisi oleum, 461 Anodynes, 165 Antacids, 68 Anthelmintics, 87 Antidotes, 46 Antifebrin, 379 Antimonium, salts of, 287 Antipyr> tics, 188 Antipyrin, 378 Antiseptics, 205 Anti-sialagogues, 59 Antispasmodics, 165 Aperients, 86 Aphrodisiacs, 524 Apomorphine hydrochlorate, 407 Digitized by Microsoft® 654 VE T ERIN A R Y THERA PEUTICS Aqua, 323 destillata, 323 fortis, 313 laurocerasi, 369 regia, 318 Areca-nut, 497 Argeuti nitras, 246 Argentum, salts of, 246 Aristol, 384 Arnica, 461 Aromatic bitters, 452 volatile oils, 457 Arsenicum, salts of, 277 Arsenious acid, 277 antidotes for, 283 toxic effects of, 281 Arteries, 132 AsafiBtida, 476 Aspidium filix mas, 496 Asthma, 152 Astringents, 85 gastric, 67 intestinal, 85 vascular, 132 Atropine, 415 compared with morphine, 403 Aurantium, 456 Balls, administration of, 535 or boluses, 530 Balsam, Friar's, 473 Peru, 475 Tolu, 475 Barbadoes aloes, 484 Barley water, 519 Baths, 202 Tu.kish, 203 Belladonna, 414 compared with opium, 403 Benzoic acid, 473 benzoin, 473 compound tincture of, 473 Bichloride of methjiene, 357 B smuth, salts of, 290 subnitrate, 290 Bitters, 452 Blistering, hints on, 526 Blisters, 195 Blood, agents acting on, 111 Blue stone, 251 Body-heat, agent^^ acting on, 185 Boracic acid, 319 Borax, 319 Boric acid, 319 Boro-glyceride, 319 Brandy, 325 Bromides, 299 Bromum, 299 Brucine, 439 Buchu, 504 Buckthorn, syrup of, 495 Butttr of antimonj , 286 Butyl chloral hydrate, 362 Cade, oil of, 469 Caffeine, 443 Calabar bt an , 427 Calamine, 249 Calcii hypophosphis, 276 Calcium, salts of, 234 Calomel, 269 Calumba, 452 Calx, 234 chloriuata, 236 sulphurata, 302 Cambogia, 482 Camphor, 471 Cannabis indica, 408 Cantharides, 523 Capsicum, 477 Caraway, 461 Carbo animalis, 306 ligni, 306 Carbolic acid, 369 Carbon compound'', 325 Cardiac stimulants, 130 Cardiac depressants, 131 Carminatives, 68 Carron oil, 234 Caryophyllum, 457 Cascara sagrada, 494 Cassia, 490 Castor oil, 491 Cataplasmata, 203 Catechu, 501 Cathartics, 86 Cattle, actions of medicines on, 39 Caustic, lunar, 246 Caustics, 206 Cautery, actual, igg Cayenne pepper, 477 Cererbal stimulants, 160 Digitized by Microsoft® INDEX 555 Cerebral depressants, 160 Cetaoeum, 522 Oevadilla, 390 Chalk, 235 Charcoal, 306 Chaulmugra oil, 520 Cherry laurel, 369 Chinoline, 380 Chloralamid, 362 Chloral hydrate, 358 in milk fever, 361 Chloric ether, 337 Chlorine, 292 Chlorodyne, 338 Chloroform, 337 as an anse thetio, 344 method of administering, 346 spirits of, 337 Cliolagogues, 87 Chromic aci^i, 321 Cinchona, 505 Circulatory system, agents acting on, 130 Circulatory stimulants, 130 Circumstances modifying the action of medicines, 33 Citric acid, 322 Citrine ointment, 273 Climate, eflfejts of on action of medicines, 44 Cloves, 457 Cocaine, 412 Codeine, 396 Cod-liver oil, 522 Colchicum, 392 Cold applications, 203 Colic, spasmodic, treatment of, 99 flatulent, treatment of, 97 CoUyria, 548 Colooynth, 481 Combination of drugs, 44 Condy's fluid, 222 Conlum, 426 Consciousness, measures influenc- ing, 161 Constipation, 89 treatment of, 94 Constringents, 85 Contraindications, 32 Convallaria, 450 Copper, salts of, 251 Copperas, 258 Cord, spinal, agents acting on, 160 Coriander, 461 Cornutine, 436 Correctives, 47 Corrosive sublimate, 268 Cough, 23 varieties of, 23 treatment of, 152 Counter-irritants, 195 uses of, 200 Counter-irritation, theory of, 197 Creasote, 382 Creolin, 375 Creta, 235 Croton chloral, 362 Croton oil, 479 Cumulative drugs, 43 Cupri sulpha', 251 Curare, 427 Cusso, 497 Dandelion, 495 Daturine, 424 Decoctions, 211 Delphinine, 391 Demulcents, 59 Deodorants, 205 Depressants, motor, 150 Diagnosis, 6 Diaphoretics, 186 Diarrhoea, 89 treatment of, 96 Diffusible stimulants, 130 Digitalin, 444 Digitalis, 444 Diseases modify the action of medicines, 40 Disinfectants, 205 gastric, 67 Dispensing, 529 Diuretics, 173 Dogs, actions of medicines on, 39 Donovan's solution, 272 Doses, 41 Dover's powder, 394 Drastics, 84 Drenches, bints on administering, 536 Duboisine, 424 Dyspepsia, 69 Digitized by Microsoft® 556 VETERINARY THERAPEUTICS Dyspepsia, treatment of, 75 Dyspnoea, 148 treatment of, 151 Easton'a syrup, 268 Ecbolics, 437 Elaterium, 481 Bmetene, 502 Emetics, 78 Empirical treatment, 55 Enemata, 100 Enteritis, 91 Epsom salt, 237 Ergot, 436 Ergotin, 436 Bscharotics, 206 Eserene, 427 Essences, 211 Ether, 354 gpirit of nitrous, 364 Eucalyptus, oil of, 470 Euonymin, 495 Euonymus, 495 Expectant treatment, 8, 55 Expectorants, 146 Bxtracta, 211 Eye, agent.s acting on, 207 Eebrifuges, 188 Fenugreek, 461 Eerrous sulphate, 258 Ferrum, salts of, 254 Fever, 19, 188 simple, 20 treatment of, 193 Filix mas, 496 Flour, 519 Fomentations, 203 Form and mode of administration of drugs, 33 Foundations of rational treatment, 53 Fowler's solution, 277 Foxglove, 444 Frequency of administration of drugs, 42 Friar's balsam, 473 Galla, 498 Gallic acid, 498 Gamboge, 482 Gastric stimulants, 66 sedatives, 67 disiufectants, 67 vascular stimulants, 67 astringents, 67 tonics, 67 specific nervo-muscular stimu- lants, 67 Gastritis, 73 treatment of, 76 Gelatinum, 522 Gelsemium, 435 General therapeutics, 48 General symptoms of disease, 6 Gentian, 45 Gin, 326 Ginger, 460 G'auber's salts, 223 Glycerina, 212 Gl3cerinum, 516 Glycerinum belladonnse, 414 Glycyrrhiza, 518 Goulard extract, 244 Green vitriol, 258 Grey powder, 267 Gum acacia, 517 ammoniac, 476 b nzoin, 473 tragaeanth, 517 Habit, modifying the action of drugs, 43 HcEraatinics, 112 Hffimatoxylon, 501 Hgemorrhage, 136 treatment of, 139 Hiemostatics, 206 Hamamelis, 502 Hartshorn, spirits of, 228 Health, 49 Heart, agents acting c n the, 130 affections of, 133, 135 Heat of body, measures affecting, 185 Hellebore, 390 Hemlot^k, 426 Hemp, Indian, 408 Henbane, 422 Homatropine, 415 Honey, 523 Horse, actions of medicines on, 37 Digitized by Microsoft® INDEX 557 Hydragogues, 86 Hydrargyrum, 263 preparations of, 263 Hydrastis, 456 Hydrate of chloral, 358 Hydrochloric acid, 315 Hydrocyanic acid, 366 Hyosoyamine, 423 Hyoscyamus, 422 Hypnotics, 162 H^podermii'- injections, 35 Hypophosphites, 276 Ichthyol, 381 Idiosyncrasies, 32 Iranaediate local action, 29 Immediate treatment, 55 Incompatibility, 45 chemical, 45 physiological, 46 Indian hemp, 408 Infusions, 211 Inhalations, 36 Injection, hypodermic, 35 intratracheal, 36 intravenous, 36 Intestinal astringents, 85 Intestines, agents acting on, 84 Iodine, 293 lodism, 295 Iodoform, 383 lodol, 384 Ipecacuanha, 502 Iron and its medicinal salts, 254 Jaborandi, 432 Jalap, 482 Jalapin, 482 Juniper, 469 Kairin, 380 Kamala, 497 Kidneys, agents acting on, 173 Kino, 501 Kousso, 497 Lanolin, 521 Lard, 521 Laudanum, 394 Laurocerasus, 369 Lavender, 460 Laxatives, 86 Lead, salts of, 241 antidotes, 243 toxic effects, 242 Lime, 234 water, 234 Liniments, 212 Linseed meal, 518 oil, 493 Liquor ammonige, 2i8 aoetatis, 233 arsericalis, 277 [272 arsenici et hydrargyri iodidi, atropinae sulphatis, 415 calcis, 234 ferri perchloridi, 260 potasseE, 218 sodii ethylatis, 357 Liquorice, 518 Litharge, 243 Liver, agents acting on, 104 Lobelia, 425 Logwood, 501 Lotions, 212 Lunar caustic, 246 ■ Magnesium and its preparations, 237 Male fern, 496 Marsh mallows, 519 Mel, 523 Mentha piperita, 459 Menthol, 460 Mercury and its preparations, 263 and zinc cyanide, 274 Metabolism, 117 Methylated spirit, 326 Methylene, bichloride of, 357 Mixtures, 212 Murphina, 395 acetas, 396 hydrochloras, 395 sulphas, 396 Morrhuae oleum, 522 Muriatic acid, 315 Muscarine, 434 Mustard, 477 as a counter- irritant, 478 Mydriatics, 207 Myotics, 207 Myrrh, 475 Digitized by Microsoft® 558 VETER IN A R Y THERA PEUTICS Naphthalin, 375 Naphthol, 375 Narcotics, 161 Natural recovery, 164 Nervous system, agents acting on, 157 Nicotine, 424 Nitre, 218 sweet spirit of, 364 Nitric acid, 313 Nitrite of amyl, 362 Nitroglycerinum, 364 Nitro- hydrochloric acid, 318 Nitrous ether, 364 oxide gas, 336 Nux vomica, 438 Oils, aromatic volatile, 457 Oleatum hydrargyri, 268 Oleum anisi, 461 cadinum, 469 calcis, 234 crotonis, 479 eucalypti, 470 juniperi, 469 lavandulffi, 460 lini, 493 menthffi piperitae, 459 morrhuae, 522 olivss, 515 picis, 468 ricini, 491 rosmarini, 460 terebintbinas, 463 Olive oil, 515 Opium, 394 preparations of, 394 Orange, 456 Pain, 163 treatment of, 167 Paraffinum molle, 384 Paraldehyde, 362 Paralysis, 163 Paramorphine, 402 Paregoric, 394 Pareira, 504 Peppermint, 459 Peppers, 477 Permanganate of potash, 221 Pharmacodynamics, 50 Pharmacology, 4 Pharmacy, 529 Phenacetin, 380 Phenazone, 378 Phosphate of soda, 277 Phosphorus, 275 Physiological action, 26 incompatibles, 46 Physostigmine, 427 Pilocarpine, 433 Pix liquida, 468 Plethora, 112 Plumbism, 242 Plumbum, salts of, 241 Podophyllin, 483 Potassii bromidum, 299 iodidum, 293 Potassium, salts of, 215 Poultices, 203 Powders, 529 Prescribing, 31, 532 hints on, 532 Prescription, the, 46, 532 Prescriptions, 539 Preventive treatment, 54 Proof spirit, 325 Prussic acid, 366 Pulse, varieties of, 13 Pupil, agents acting on, 206 Purgatives, 84 hints on, 485 Pyoktanin, 377 Pyrexia, 188 Pyridine, 424 Pyrogallic acid, 500 Quaspia, 454 Quinidine, 505 Quininae sulphas, 505 Quinine, 505 RattonM treatment, 55 Recovery, natural means of, 52 Rectified spirit, 325 Rectum tube. Smith's, 101 Remote local action, 31 Resin, 468 Resorcin, 375 Respiratory system, agents acting on, 144 Rhamnus catharticus, 495 Digitized by Microsoft® INDEX 559 Rhubarb, 490 Rioini oleum, 491 Rosemary, 460 Rubefacients, 196 Ruminants, actions of medicines on, 39 Rye, ergot of, 436 Sal ammoniac, 232 Sal volatile, 230 Salioinum, 510 Salicylate of soda, 510 Salicylic acid, 511 Saline diuretics, 175 Saline purgatives, 86 Salol, 381 Salt, common, 225 Epsom, 237 Glauber's, 223 Saltpetre, 218 Santonin, 496 Sapo durus, 515 Sapo mollis, 515 Scammony, 483 Scilla, 451 Sedatives, cardiac, 131 cerebral, 160 intestinal, 87 pulmonary, 145 Senna, 490 Serpentaria, 456 Sherry, 325 Sialagogues, 58 Silver salts, 246 Sinapis, 477 Skin, agents acting on, 185 Sleep, 156 Soap, 515 Sodii bicarbonas, 222 benzoas, 473 biborate, 319 bromidum, 299 hypophosphis, 276 hjposulphis, 224 iodidum, 296 nitris, 364 salicylas, 510 valerianas, 475 Sodium Ealts, 222 Specific action of drugs, 30 Spermaceti, 522 Spirit of nitre, 364 Spirits, 212 Spiritus setheris nitrosi, 364 ammonisa aromaticus, 230 rectificatus, 325 tenuior, 325 vini gallici, 325 Squill, 451 Staphisagria, 391 Starch, 519 Stavesacre, 391 Stimulants, cardiac, 130 cerebral, 160 oircula'ory, 130 gastric, 66 hepatic, 105 intestinal, 86 local, 157 motor, 160 renal, 175 respiratory, 145 Stomach, agents acting on, 66 Stomachics, 66 Stramonium, 424 Strophanthus, 450 Strychnine, 439 Styptics, 206 Sudorifics, 186 Sulphonal, 362 Sulphur, 302 Sulphuric acid, 311 Sulphurous acid, 306 Surface of the body and ex- tremities, symptoms furnished by, 24 Surgical applications, 205 Symbols, 530 Symptoms, general, of disease, 6 Syncope, 140 Syrups, 212 Tabaci folia, 424 Tannic acid, 498 Tar, 468 Taraxacum, 495 Tartar emetic, 287 Tartaric acid, 322 Taste, loss of, 69 Temperature, 19 Terebene, 468 TerebinthinsB, oleum, 463 Digitized by Microsoft® 560 VETERINARY THERAPEUTICS Thallin, 380 Thebaine, 402 Therapeutics, general, 48 special, 240 Theriaca, 517 Thioform, 513 Thymol, 460 Tincturae, 212 Tobacco, 424 Toleration of drugs, 43 Tolu, balsam of, 475 Tonics, hsematinic, 112 stomachic, 67 Toxicology, 5 Tragacanth, 517 Treacle, 517 Treatment, different kinds of, 54 Turpentine, 463 Tympanitis, 91 Unguenta, 212 Urine, agents influencing, 174 Uva ursi, 504 Valerian, 475 Vaseline, 384 Venesection, therapeutical value of, 141 Veratrine, 390 Vermicides, 87 Vermifuges, 88 Vesicants, 196 Veterinary pharmacy, 528 Villate's injection, 253 Vina, 212 Vinegar, 322 Visible mucous membranes, 17 Volatile oils, 457 Vomition, 77 Wash, black, 271 yellow, 272 Water, 323 baths, 202 Weights and measures, 530 Wheat-flour, 519 White lotion, 245 White precipitate, 273 Willow-bark, 510 Wounds, treatment of, 204 Zinc, salts of, 249 Zinci sulphocarbolas, 370 oarbonas, 249 ehloridum, 251 oxidum, 249 sulphas, 250 valerianas, 475 Zingiber, 460 THE END. Bailli&re, Tindcd{ i& Qox^ 20 and 21, King William Street^ Strand. Digitized by Microsoft® WILLIAM R. JENKINS' Veterinary Books. 1899. (*) Single asterisk designates New Books. (**) Double asterisk designates Recent Publications. For extended notices, see the special advertise- ments at the back of the Catalogue. ANDERSON. "Vice in the Horse" and other papers on Horses and Biding. By E. L. Anderson. Demy, 8vo, cloth 2 00 — " How to Ride and Scliool a Horse." With a System of Horse Gymnastics. By Edward L. Anderson. Or. 8yo , . , 1 00 Digitized by Microsoft® 4 Veterinary Catalogue of William B. Jenkins C*)CADIOT. "Eoaring in Horses." Its Pathology and Treatment. This work represents the latest development in operative methods for the alleviation of roaring. Each step is most clearly defined by excellent full-page illustrations. By P. J. Cadiot, Professor at the Veterinary School, Alfort. Trans. Thos. J. WattDollar, M.K.C.V.S., etc. Cloth 50 (") _" Exercises in Eqnine Surgery." By P. J. Cadiot. Tran8lat«d by Prof. A. W. Bitting, M.D.,V.S. ; edited by Prof. A. Liautard, M.D.V.S. 8vo, cloth, illus- trated 2 50 (•)— A Treatise on Veterinany Tlierapeutics of the Domestic Animals. By P. J. Cadiot and J. Alvary. Translated by Prof. A. Liautard, M,D.,V.S. Part I, Vol. 1, 8vo, 93 pp., 45 illustrations 1 00 {Part II, in Preparation). CHAVVEAU. "Tlie Comparative Anatomy of tlie Domesticated Animals." By A. Chauveau. New edition, translated, enlarged and entirely revised by George Fleming, F.K.C.V.S. 8vo. cloth with 585 Illustrations 5 75 CLARKE. "Horses' Teetli." A Treatise on their Anatomy, Pathology, Dentistry, etc. Revised and enlarged. By W. H. Clarke. 12mo, cloth 2 50 -- "CJiart of the Feet »nd Teeth of Fossil Horses." 25 Digitized by Microsoft® 861-853 Sixth Avenw (cor. mh St.), New York. CLEAVELAND. "Pronouncing Medical Lexicon." Pocket edition. Cloth 75 COUMTEKAT. "Manual of Veterinary Medicine and Surgery." By Edward Courtenay, V. S. Crown, 8vo, clotli 2 75 COX, "Horses : In Accident and Disease." The sketches introduced embrace various attitudes which have been observed, such as in choking ; the disorders and accidents occurring to the stomach and intestines ; affection of the brain ; and some special forms of lame- ness, etc. By J. Koalfe Cox, F.K.C.V.S. Svo, cloth, fully Illustrated 1 00 CURTIS. "Horses, Cattle, Sheep and Swine." The origin, history, improvement, description,characteri8- tics, merits, objections, etc. By Geo. W. Curtis, M.S.A. Superbly illustrated. Cloth, $2 00; half sheep, $2.75 ; halt morocco 3 50 {*)DAL,ItYMPLE. "Veterinary Obstetrics." A com- pendium for the use of advanced students and Practi- tioners. By W. H. Dairy m pie, M. K. C. V. S., principal of the Department of Veterinary Science in the Louisiana State University and A. & M. College ; Veterinarian to the Louisiana State Bureau of Agriculture, and Agricultural Experiment Stations; Member of the United States Veterinary Medical Associations, etc. Svo, cloth, with many illustra- tions 2 50 Digitized by Microsoft® Veterinary Oatatogue of Wittiam ti. Jenkins DWrnn. ''Seats and Saddles." Bits and Bitting, Draught and Harness and the Prevention and Cure ol Eestiveness in Horses. By Francis Dwyer. Illus- trated. 1 vol., 12mo, cloth, gilt 1 50 {'*)FLiEMING. "Veterinary Obstetrics." Including the Accidents and Diseases incident to Pregnancy, Parturi- tion, and the early Age in Domesticated Animals. By Geo. Fleming, F.K.O.V.S. With 212 illustrations. New edition revised, 226 illustrations, 758 pages. -.6 25 773 pages,8vo, cloth (old edition) 3 50 — "Rabies and Hydrophobia." History. Natural Causes, Symptoms and Prevention. By Geo. Fleming, M. K.O.V.S. 8vo, cloth 3 75 — "Tuberculosis." From a Sanitary and Pathological Point of View 25 — " The Contagious Diseases of Animals." Their influence on the wealth and health of nations. 12mo, paper 25 — "Operative Veterinary Surgery." Part I, by Dr. Geo. Fleming, M.B.C.V.S. This valuable work, the most practical treatise yet issued on the subject in the English language, is devoted to the common operations of Veterinary Surgery; and the concise descriptions and directions of the text are illus- trated with numerous wood engravings. 8vo,cloth.2 75 Second volume in preparation. Digitized by Microsoft® 851-853 Sixth Avenue {cor. iSth St.), New ^orh. & Human ami Animal Variolae." A Study in Comparative Pathology. Paper 25 'Animal Plagues." Their History, Nature, and Prevention. By George Fleming, P. E. C. V. S., etc. First Series. 8vo, cloth, $6.00; Second Series. 8vo, cloth 3 00 " Roaring in Horses." By Dr. George Fleming, F.B.C.V.S. A treatise on this peculiar disorder of the Horse, Indicating its method of treatment and curability. 8vo, cloth, with col. plates 1 50 FLEMING-NEUMANN. "Parasites and Parasitic Diseases of the Domesticated Animals." A work which the students of human or veterinary medi- cine, the sanitarian, agriculturist or breeder or rearer of animals, may refer for full information regarding the external and internal Parasites— vegetable and animal — which attack various species of Domestic Animals. A Treatise by L. G. Neumann, Professor at the National Veterinary School of Toulouse. Translated and edited by George Fleming, C. B., L.L. D.,P.R.O.V.S. 873 pages, 365 illustrations, cloth.7 50 ORES SWELL. "The Diseases and Disorders of the Ox." By George Gresswell, B.A. With Notes by James B. Gresswell. Crown, 8vo, cloth, ill us. ...3 50 — " Diseases and Disorders of the Horse." By Albert, James B., and George Gresswell. Crown, 8vo, illus- trated, cloth 1 76 Digitized by Microsoft® 10 Veterinary Catalogue of William tt. Jenkins 6RESSWELL. Manual of "The Theory and Practice of Equine Medicine." By J. B. Gresswell, F.K.C.V.S., and Albert Gresswell, M.R.C.V.S., second edition, enlarged, 8vo, cloth 2 75 — " Veterinary Pharmacology and Therapeutics." By James B. Gresswell, P.E.O.V.S. 16mo, cloth . . .1 50 — " The BoTine Prescriber." For the use of Veterina- rians and Veterinary Students. By James B. and Albert Gresswell, M.K.C.V.S Cloth 76 — "The Equine Hospital Prescriber." Drawn up for the use of Veterinary Practitioners and Students. By Drs. James B. and Albert Gresswell, M.R.C.V.S. Cloth 75 — " Veterinary Pharmacopoeia, Materia Medica and Therapeutics . " By George and Charles Gresswell, with descriptions and physiological actions of medi- cines. By Albert Gresswell. Crown,8vo,cl 2 75 GOTTHEIL. "A Manual of General Histology." By Wm. S. Gottheil, M.D., Professor of Pathology in the American Veterinary College, New Tork ; etc., etc. Histology is the basis ot the physician's art, as Anatomy is the foundation of the surgeon's science. Only by knowing the processes of life can we under- stand the changes of disease and the action of remedies ; as the architect must know his building materials, so must the practitioner of medicine know the Intimate structure ot the body. To present this knowledge in an accessible and simple form has been the author's task. 8to., cloth, 118 pages, fully illustrated 1 00 Digitized by Microsoft® 851-8S3 Sixth Avenue (cor. iSth St.), New Yark. 11 {*')HASSLOCH. "A Compend of Teterinary Materia Medica and Therapeutics." By Dr. A. C. Hassloch, V.S., Lecturer on Materia Medica and Tlierapeutics, and Professor of Veterinary Dentistry at tiie NewYorli College of Veterinary Surgeons and School of Compa- rative Medicine, N. Y, 12mo, cloth, 225 pages . .1 50 DHEATLEy. "The Stock Owner's Guide." A handy Medical Treatise for every man who owns an ox or cow. By George S. Heatley, M.K.C.V. 12mo, cloth 1 25 — "The Horse Owner's Safeguard." A handy Medical Guide for every Horse Owner. 12mo, cloth 1 50 — " Practical Veterinary Remedies." 12mo, cloth 1 00 HIIjL. "The Principles and Practice of Bovine Med- icine andSurgery." By J. WoodroiTe Hill, F.E.C.V.S. Cloth. (Temporarily out of print). (We have one copy of this work that can be had for $15.00.) SILL,. "The Management and Diseases of the Dog." Containing full instructions for Breeding, Bearing and Kenneling Dogs. Their Different Diseases. How to detect and how to cure them. Their Medicines, and the doses in which they can be safely administered. By J. Woodroffe Hill, F.E.C.V.S. 12mo, cloth, extra fully illustrated.. 2 00 Digitized by Microsoft® 14 Veterinary Catalogue of William R. Jenkins (**) EIA UTARD. "Median Neurotomy in the Treatment of Chronic Tendinitis and Periostosis of the Fetlock." By C. Pellerin, late Eepetitor of Clinic and Surgery to the Alfort Veterinary School. Translated with addi- tional facts relating to it, by Prof. A. Liautard, M.D., V.M. Having rendered good results when performed by himself, the author believes the operation, which consists in dividing the cubito-plantar nerve and in excising a portion of the peripherieal end, the meanp of improving the conditions, and consequently th9 values of many apparently doomed animals. Agricul- ture in particular will be benefited. The work is divided into two parts. The first covers the study of Median Neurotomy itself ; the second, the exact relations of the facts as observed by the author. 8vo., boards 1 00 (**) — "Manual of Operative Teterinary Surgery." By A. Liautard, M.D., V.M., Principal and Professor of Anatomy, Surgery, Sanitary Medicine and Juris- prudence in the American Teterinary College; Chevalier du Merite Agricole de France, Honorary Fellow of the Boyal College of Veterinary Surgeons (London), etc., etc. 8vo, cloth, 786 pages and nearly 600 illustrations , 6 00 — "Animal Castration." A concise and practical Treatise on the Castration of the Domestic Animals. The only work on the subject in the English language. Illustrated with (prt^-four cuts, 12mo, cloth... 2 00 Digitized by Microsoft® 851-853 Sixth Avenue (cor. 4Sth St.), New York. 15 (**) "Vade Mccum of Equine Anatomy." By A. Liautard, M.D.V.S. Dean of the American Veterinary College, 12mo. cloth. New edition, with illustrations 2 00 — "Translation of Zundel on tlie Horse's Foot." Cloth 2 00 — " How to TeU the Age of the Domestic Animal." Bj Dr. A. Liautard, M.D., V.S. Profusely illustrated. 12mo, cloth 50 — "On the lameness of Horses." By A. Liautard, M.D.,V.S 2 50 See also "Cadiofs Surgery." (*)— " A Treatise on Veterinary Therapeutics of the Domestic Animals." (See Cadiot.) LONG. "Book of the Pig." Its selection, Breeding, Feeding and Management. 8vo, cloth i 26 (**)LOfFJE. "Breeding Racehorses by the Figure System." Compiled by the late C. Bruce Lowe. Edited by William Allison, " The Special Commis- sioner," London Sportsman, Hon. Secretary Sporting League, and Manager of the International Horse Agency and Exchange. With numerous fine illustra- tions of celebrated horses. Quarto, cloth 7 50 C*)LUPTON. "Horses: Sound and Unsound," with Law relating to Sales and Warranty. By J. Irvine Jjupton, F.^R.O,y.^. 8vo, cloth, ^ll^strate4 1 25 Digitized by Microsoft® 16 Veterinary Catalogue of William B. Jenkins — "The Horse." As he Was, as he Is, and as he Ought to Be. By J. I. Lupton, F.K.C.V.S. Illus- trated. Crown, 8vo 1 40 MAONER. " Facts for Horse Owners." By D. Magner. Upwards of 1,000 pages, illustrated with 900 engrav- ings. 8vo, leather binding _. 7 50 MAYHJSW. "The Dlnstrated Horse Doctor." An accurate and detailed account of the Various Diseases to which the Equine Race is subject ; together with the latest mode of Treatment, and all the Requisite Pre. scriptions written in plain English. By E. Edward Maytiew, M.R.C.V.S. Illustrated. Entirely new edition, 8vo, cloth , 2 75 McBBIDE. "Anatomical Outlines of the Horse." 12mo, cloth. Reduced to 1 50 McCOMBIE. "Cattle and Cattle Breeders." Cloth 1 00 WFADYEAN. "Anatomy of the Horse." A Dis- section Guide. By J. M. M'Fadyean, M.R.C.V.S. This book is intended for Veterinary students, and offers to them in its 48 full-page colored plates numer- ous other engravings and excellent text, the most valuable and practical aid in the study of Veterinary Anatomy, especially in the dissecting room. 8vo, clpth . , , . , , , 5 50 Digitized by Microsoft® 851-853 Sixth Avenue (cor. mh St.), New Vafk. 17 " Comparative Anatomy of the Domesticated Ani- mals." By J. M'Fadyean. Profusely illustrated, and to be issued in two parts. Part I — Osteology, ready. (Part II. in preparation.) PBper,2.50; oloth,2.75 STILLS. "How to Keep a Dog in the City." By Wesley Mills, M.D., V.S. It tells how to choose, manage, house, feed, educate the pup, how to keep him clean and teach him cleanliness. Paper 25 (**)MOLLEIt. "OpcratlTe Veterinary Snrgery." By Professor Dr. H. MoUer, Berlin. Translated and edited from the 2d edition, enlarged and improved, by John A. W. Dollar, M.B.C.S. Prof. Holler's work presents the most recent and complete exposition of the Principles and Practice of Veterinary Surgery, and is the standard text-book on the autfject throughout Germany. Many subjects ignored in previous treatises on Veterinary Surgery here receive full consideration, while the better known are presented under new and suggestive aspects. As Prof. Moller's work represents not only his own opinions and practice, but those of the bes Veterinary Surgeons of various countries, the trans- lation cannot fail to be of signal service to American and British Veterinarians and to Students of Veter* inary and Comparative Surgery. I vol., 8vo. 722 pages, 142 Jllustration? 5 25 Digitized by Microsoft® 18 Veterinary Catalogue of William R. Jenkins MOHETON. " On Horse-breaking." 12mo, cl 50 rWOSSEJuMAN-LlENAUX. "Veterinary Micro- biology." By Professors Mosselman and Lienaux, Nat. Veterinary College, Cureghem, Belgium. Trans- lated and edited by K. K. Dinwiddie, Professor of Veterinary Science, College of Agriculture, Arkansas State University. 12nio, cloth, 342 pages 2 00 PEGLEB,. "The Book of the Goat." 12mo, cloth 1 75 {")PELZ,EBIN. "Median Neurotomy in the Treatment of Chronic Tendinitis and Periostosis of the Fetlock." By C. Pellerln, late repetitor of Clinic and Surgery to the Alfort Veterinary School. Translated, with Addi- tional Facts Belating to It, by Prof. A. Liautard, M.D , V.M. 8vo, boards, illustrated 1 00 See also " Liaula/rd." {•*)NOCAB.D. "The Animal ^Tuberculoses, and their Relation to Human Tuberculosis." By Ed. Nocard, Professor of the Alfort Veterinary College. Trans- lated by H. Scurfield, M.D. Ed., Ph. Camb. Perhaps the chief interest to doctors of human medicine in Professor Nocard's book lies in the demonstration of the small part played by heredity, and the great part played by contagion in the propa- ' gatlon of bovine tuberculosis. It seems not unreason- able to suppose that the same is the case for human tuberculosis, and that, if the children of tuberculosis parents were protected from infection by cohabitation or ingestion, the importance of heredity as a cause of the disease, or even of the predisposition to it, would dwindle away into insignificance. 12mo, cloth, 143 pages 1 00 Digitized by Microsoft® 851-853 Sixth Avenue {cor. 48t7i. St.), New York. 19 PBOCTOM. " The Management and Treatment of the Horse " in the Stable, Field and on the Boad. By William Proctor. 8vo 2 40 PETERS. " A Tuberculous Herd— Test with Tuber- culin." By Austin Peters, M. E. C. V. S., Chief Inspector of Cattle for the New York State Board of Health during the winter of 1892-93. Pamphlet 25 REYNOLD. "Breeding and Management of Draught Horses." 8vo, cloth 140 ROBERTSON. " The Practice of Equine Medicine.' A text-book especially adapted for the use of Veter- inary students and Veterinarians. By W. Robertson, Principal and Professor of Hippopathology in the Royal Veterinary College, London. 8vo. cloth, 806 pages,revised edition. (Temporarily out of print).6 25 ('*)ROBERQE. " The Foot of the Horse," or Lame- ness and all Diseases of the Feet traced to an Unbal- anced Foot Bone, prevented or cured by balancing the toot. By David Koberge. 8vo, cloth 6 00 OSEWELli. "The Examination of Horses as to Soundness and Selection as to Purchase." By Ed- ward Sewell, M.B.C.V.S.L. 8vo, paper . . .1 60 Digitized by Microsoft® 22 Veterinary Catalogue of William R. Jenkins No. 5. "The Elementary Anatomy, Points, and But- cher's Joints of the Ox." Ten colored illustrations —1. Skeleton; 2. Nervous System; 3. Digestive System (Bight Side) ; 4. Respiratory System ; 5. Points of a Fat Ox ; 6. Muscular System ; 7. Vascular System ; 8. Digestive System (Left Side) ; 9. Butcher's Sections of a Calf ; 10. Butcher's Sections of an Ox ; with full description 1 25 WA.LLET, "Hints on the Breeding and Bearing of Farm Animals." 12mo, cloth 80 — " Four BoTine Scourges. " (Pleuro - Pneumonia, Foot- and Mouth Disease, Cattle Plague and Tubercle.) With an Appendix on the Inspection of Live Animals and Meat. Illustrated, 4to, cloth. .6 40 {")WAl,LET. "A Practical Guide to Meat Inspection." By Thomas Walley, M.R.C.V.S., formerly principal of the Edinburgh Royal (Dick) Veterinary College; Professor of Veterinary Medicine and Surgery, etc. Third Edition, thoroughly revised, with forty-five colored illustrations, 12mo, cloth 3 00 An experience of over 30 years in his profession and a long ofQcial connection (some sixteen years) with Edinburgh Abattoirs have enabled the author to gather a large store of information on the subject, which he has embodied' in his book. Dr. Walley's opi- nions are regarded as the highest authority on Meat Inspection. (") IFI££X4MiS'. "Principles and Practice of Veter- inary Medicine." New author's edition, entirely revised and illustrated with numerous plain and color- ed plates. By W. 'Williams, M.R.C.V.S.8vo., el. .6 00 Digitized by Microsoft® 851-853 Sixth Avenue {cor. iSth St.), New York 23 (*•) "Principles and Practice of Yeterinary Surgery." New author's edition, entirely revised and illustrated with numerous plain and colored plates. By W. Williams, M.R.C.V.S. 8vo, eloth 6 00 (*)WYMA.N. "The Clinical Diagnosis of Lameness in tike Horse." By W. E. A. Wyman, V.S., Prof, ol Veterinary Science, Clemson A. & M. College, and Veterinarian to the South Carolina Experiment Sta- tion. 8vo, cloth, illustrated „ 2 50 ZUNDEJL. "The Horse's Foot and Its Diseases." By A. Zundel, Principal Veterinarian of Alsace Lorraine. Translated by Dr. A. Liautard, V.S. 12mo, cloth illustrated 2 00 ZUILli. "Typhoid Fever; or Contagions Influenza in the Horse." By Prof. W. L. Zuill, M.D.,D.V.S. 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