CORNELL UNIVERSITY THE THIS BOOK IS THE GIFT OF TttnojYN.uJ5 M^ra^^M .flOu, ftm<)u MiiiaCt -Xrw^fifletLffiw ....Ii;.wifltei o^..iJU..-.eftU^ Cornell University Library SF 967.T5M82e The elimination of tubercle bacilli from 3 1924 000 225 817 Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924000225817 THE ELIMINATION OF TUBERCLE BACILLI VFROM INFECTED CATTLE < .1 . :Mi^' i i^iOV^'iO i§i|. M VERANUS A. MOORE '■L U^ - (Professor of Comparative Pathology and Bacteriology, N.y. state Veterinary ■~-- , College at Cornell Universityj Ithaca, N.Y.) Re'printed from Thb Journal or Mbdical Research, Volume XXIV., No, 3 (New Series, Vol. XIX., No. 3), pp. JiJ-JaS. Ju"e, 191 1 BOSTON MASSACHUSETTS U.S.A. CORNELL UNIVERSITY THE THIS BOOK IS THE GIFT OF TCJNArv^uJS. J^S^vrtl. M&^ >%d,,.>AiU>i.. ivw^m^ett^ lli.UiJlXjlftN^^lrriJlx^ tHE ELIMINATION OF TUBERCLE BAClLLt FROM INFECTED CATTLE.* Veranus a. Moore. (Professor of Comparative Pathology and Bacteriology, N. Y. State Veterinary College, at Cornell University, Ithaca, N. Y. ) The report that tubercle bacilli are present in a large number of samples of market milk suggested the desira- bility of more extended studies relative to the elimination of the specific organisms from infected cattle. The results of recent examinations by Hess, Tonney and others indicate that tubercle bacilli in market milk are steadily becoming more and more numerous. The official efforts to control bovine tuberculosis by what may be called the American plan, i.e., by testing the dairy cows with tuberculin and destroying the reactors, has not been generally successful in checking the spread of the disease, as indicated by the fre- quency with which the specific organisms are found. The fault does not rest with the method but in the fact that it has not been generally applied. Other and more conservative systems of control, such for example as those introduced by Bang and Ostertag, are not acceptable because our people object to the milk from apparently sound but reacting cows. In order to secure information concerning the safety of the milk from occult cases of tuberculosis in cattle and to ascertain the extent of the immediate danger of such animals to others, a study of the elimination of tubercle bacilli was undertaken early in 1907 and the work is still under way. The first examinations were restricted to single specimens of milk or feces, or both, from cows that had been tested with tuberculin. In some cases the mixed milk of the dairy was taken. As a rule the cows from which the specimens came were free from clinical evidence of disease, but in a few cases symptoms were present. These preliminary examinations were followed later by a careful investigation * Received for publication April ii, 1911. (SI 7) 5i8 moorE. of a series of specimens of the milk and feces taken at short intervals from a smaller number of reacting cows. The methods employed varied slightly with the conditions under which the milk was received. In all cases it was cen- trifugalized, and the sediment examined microscopically. Guinea-pigs were inoculated in a number of cases when the microscopic examination suggested that possibly tubercle bacilli were present. In many cases the cream was also examined. The mixed milk came from small and larger herds. The feces were collected after the method employed by Reynolds and Beebe and also those normally passed. The feces were examined microscopically by making prop- erly stained cover-glass preparations from the surface of the normally expelled material, from the scrapings of the rectal mucosa, or from the sediment in centrifugalized specimens. Several preparations were made and examined from each specimen. In the preliminary work we examined a total of one hundred and thirty-six samples of milk and thirty-six oi feces. Of the milk samples, forty-nine were mixed and eighty-seven were from individual cows. Of the latter two had diseased udders. In all, eighty guinea-pigs were inocu- lated. They received two cubic centimeters each of the sediment from the centrifugalized tube. Sixteen of these were injected into the abdominal cavity, the others received the sediment subcutaneously. The results of these exami- ' nations were as follows : Of the forty-nine • examinations of mixed milk, tubercle bacilli were found in one specimen microscopically and no inoculations were made. Later experience suggests that possibly these were acid fast organisms other than true tubercle bacilli. It was not known to us whether or not clinical cases existed in this herd. Guinea-pigs inoculated with the mixed milk from two herds developed tuberculosis. It was known that in these herds there were clinical cases. After they were removed subsequent inoculations gave negative results. The guinea-pigs inoculated with the samples from the other mixed milk either died within a few ELIMINATION OF TUBERCLE BACILLI FROM CATTLE. 519 days from sepsis or remained well until killed for examina- tion. Thus there were two of the forty-nine samples that contained infecting organisms and possibly the third did also. This gives at the maximum a little over six per cent that contained tubercle bacilli. Of the eighty-seven examinations of the milk from individ- ual cows, tubercle bacilli were not found microscopically or by guinea-pig inoculations, except in two cases, and these were samples of milk from the cows whose udders were affected. These were the only cows that showed any clinical evidence of disease and at the time the specimens were taken the lesions in the udders were not thought to be of a tuberculous nature. Tubercle bacilli were present in very large numbers in the milk from each of these cows. They were largely outside of the tissue cells, lying free between the leucocytes and fat globules of the milk. In two specimens acid fast or timothy bacilli were present in very small numbers. They were decolorized with acidulated alcohol and guinea-pigs inoculated from these samples did not develop tuberculosis. If we exclude the two cases in which there were udder lesions, tubercle bacilli were not found in any of the samples. If they were included, a little over two per cent of the examinations were positive. The thirty-six examinations of the feces failed to reveal the presence of tubercle bacilli, either microscopically or by animal inoculation. One specimen contained a few acid fast organisms. The guinea-pigs inoculated from this specimen did not develop tuberculosis. In drawing conclusions from the results of these examina- tions, the fact must be kept in mind that they were not made from selected cases, but were made from animals in herds that were tested in regular work. The cows were kept under quite different conditions ; some were in the best of sanitary stables and others were not. The number of examinations is too small to warrant any general deductions. The results show, however, that tubercle bacilli were not present or discoverable at least in the milk or feces of a con- siderable number of specimens taken from reacting and 5 20 MOORE. apparently healthy cows. If a careful physical examination had been made and all suspicious cases removed before the bacteriological examinations of the milk and feces were undertaken tubercle bacilli would not have been found either microscopically or by guinea-pig inoculation. As the results mentioned above were obtained from the examination of material from cows in herds that were at the time undergoing the tuberculin test, they were not, except in a few cases, confirmed by further or repeated examinations. They were, however, of the same nature as many of the earlier examinations from which conclusions of a far-reaching significance have been drawn, and upon which certain sani- tary regulations have been based. It is to be regretted that in the earlier reports of milk examination for tubercle bacilli the condition of the cows from which it came was not more definitely recorded. In a few cases the statement was made that the udders were apparently free from disease but the possibility of the milk becoming infected from the feces was not so fully considered at that time. It is possible, therefore, that advanced pulmonary lesions or intestinal ulcers, without udder infection, could have been responsible, through fecal contamination, for the bacteria found in the milk. The results of our single examinations were so strikingly uniform, in that cows with udder tuberculosis were elimi- nating large numbers of tubercle bacilli with the milk and that cows reacting to tuberculin, but showing no physical evidence of the disease, were not eliminating them so far as we could determine, in either the milk or excreta, that it seemed very desirable to continue this study. It was felt that errors in operation or coincidence might have been responsible for the findings. To overcome these and to ascertain whether or not tubercle bacilli appear from time to time in the milk or feces of clinically sound but infected cows, it was decided to make a series of examinations extending over a longer period from a smaller number of reacting animals. In . order to have occult cases available for frequent examinations and to have the animals kept under known ELIMINATION OF TUBERCLE BACILLI FROM CATTLE. S^I conditions, several tuberculin reacting cows were procured and placed on our veterinary experiment station. They were of grade stock and in good condition. With two exceptions these animals were apparently in a perfectly healthy con- dition, although they gave a good tuberculin reaction. The examinations of Nos. i to 4 inclusive were begun early in July, 1909, and are still being continued on Nos. i to 3. The examinations of Nos. 6 to 12 inclusive were begun in September, 1909, and, with the exception of Nos. 6 and 12, are still being continued. Nos. 5 and 13 were clinical cases and the examinations were made during the latter stages of the disease only. All of the occult cases reacted to tuberculin in February and October, 1910, and again in February, 1911, In making these examinations the same methods were employed as were followed in the preceding work. The examinations were begun in July, 1909, and continued until January, 1911. Thirteen animals were used in these repeated tests. The work will be continued on these animals until they exhibit clinical evidence of the disease or shall have ceased to react to tuberculin. The accompanying table gives the number of examinations made from each animal and the results : 522 MOORE. NoMBER OF Examinations made from- each Animal in the Eighteen Months from July i, igog, to Dec. 31, 1910. Microscopic Examinations. No. of Animal Inoculations. No. of Animal. No. of Samples Examined. No. of Times Acid Fast Bacteria were Found in Milk. Feces. Positive Cases. Nega- tive or Died of Sepsis. Milk. Feces. Milk. Feces. M. F. Cow No. I . " " 2 . " " 3 ■ Bull " 4 . Cow ' 5 .. .. 62 ., .. J . " " 8 . " " 10 . " '* II . " " 122 " " 15I 79 61 83 19 45 S+ Dry. 67 26 37 20 Dry. 89 53 93 3a H 42 61 18 61 60 36 ■7 4 7 10 10 2 6 7 6 3 2 32 20 32 I 8 17 23 10 IS 28 14 5 4 7 S 7 II 6 2 7 I 5 3 13 3 9 4 I 8 8 8 10 I 2 5 2 I 20 11 16 8 7 10 14 9 '5 4 Total , . 491 580 S3 209 S7 67 S 3 116 1 Cows Nos. 5 and 13 were clinical cases. 2 Cow No. 6 was killed in another experiment September, 1910. 3 Cow No. 9 developed a cough in October. The positive case was in a guinea-pig inoculated in November. The cow is still under observation. A few examinations of the saliva have been made from each case, but tubercle bacilli were found in that from Nos. 5 and 13 only. The examinations were made as frequently as it was pos- sible. When acid fast bacteria were found, the preparations were carefully treated with acidulated alcohol or strong (33 1/3 per cent) nitric acid, and one or more guinea-pigs were inoculated with the material from each animal exhibiting these organisms. The inoculation of guinea-pigs with feces is not altogether satisfactory owing to the considerable number of deaths that occur from sepsis. In this work about thirty of the animals died from this cause. In every case, however, some of the guinea-pigs injected with the feces ELIMINATION OF TUBERCLE BACILLI FROM CATTLE. 523 containing acid fast bacilli lived and were later (four to six weeks) chloroformed and carefully examined. In order to test further the escape of tubercle bacilli in the milk, the milk from each of the cows Nos. i, 2, and 3 was fed to two pigs during the months of July, August, and Sep- tember, 1909. The pigs were examined post-mortem the last of October and in November without finding any evi- dence of tuberculosis. The two clinical cases were of interest. Number 5 was an old cow, exhibiting well advanced symptoms of disease. She was very poor and the supramammary lymph gland was considerably enlarged. When received she ate well. Microscopic examinations of the milk and feces were made and several guinea-pigs were inoculated. These, however, were negative until she developed a cough, when the sputum and feces were found to contain tubercle bacilli. The enlarged supramammary lymph gland continued to increase in size and after a few weeks the process extended into the mammary gland itself. Soon after this took place the milk contained tubercle bacilli. This was determined by the guinea-pigs that were inoculated with the specimens contain- ing these organisms developing generalized tuberculosis. This cow was killed later and found to be suffering with generalized tuberculosis. There were old and walled-off lesions in the lungs, also a successive series of young and older miliary tubercles. About one-quarter of one mammary gland was tuberculous. Cow No. 13 was an advanced case of tuberculosis procured to infect a small pasture. She had a bad cough, was thin and not giving milk. The microscopic examination of the feces and expectoration showed acid fast bacteria, pre- sumably tubercle organisms. The guinea-pigs inoculated with the feces died of sepsis, but the one inoculated with the expectoration died of generalized tuberculosis in thirteen days. This cow died before further tests were made. The autopsy showed advanced pulmonary lesions of tuberculosis. Number 4 was a young bull. He developed evidence of tuberculosis and was killed in the fall of 1909. There were 524 MOORE. thirty-two examinations of his feces, but they did not reveal the presence of tubercle bacilli. The post-mortem did not reveal extensive lesions in the lungs and the intestines were normal. Number 9 was an occult case at the beginning of the work in 1909. In October, 1910, she developed a cough and began to grow thin. The guinea-pigs inoculated with her milk and feces did not develop tuberculosis until the one inoculated with the feces in November. Inoculations made from the feces after the time covered by this paper gave positive results. The milk still remained uninfected. Reichel and Deubler found in the examination of the feces of forty tuberculous animals that cattle with "open lesions of tuberculosis, and throwing off tubercle bacilli in the feces or rectal scrapings, as a rule show physical symptoms of tuberculosis and are the most active disseminators of the disease." Further they found that " tuberculin reacting cattle do not necessarily throw off tubercle bacilli in the feces, until the development of ' open ' lesions of tubercu- losis, in which event the condition may be detected by a con- sideration of the history, careful observation and a complete physical examination." The point has been very clearly brought out in this work that it is impossible to differentiate by means of decolorizing solutions, such as acidulated alcohol or strong solutions of nitric acid, between tubercle bacilli and certain other acid fast bacteria that frequently appear in feces of cattle. That is, certain specimens have contained acid fast bacteria that could not be distinguished from the tubercle organism, morphologically or by known staining methods which failed to produce tuberculosis in guinea-pigs. CONCLUSIONS. From the results of our examinations the following tentative ■ conclusions seem to be warranted : I. Cows with tuberculous udders eliminate tubercle bacilli with the milk. In such cases these organisms are usually present in large numbers. Elimination of tubercle bacilli Erom cattle. 525 2. Cows with glandular or pulmonary tuberculosis, in which the lesions are discharging into the bronchi, eliminate tubercle bacilli with the feces and with the droolings. In cases of intestinal tuberculous ulcers the organisms are excreted with the feces. 3. Milk is usually infected with tubercle bacilli when it is taken from cows with tuberculous udders. It may, through contamination with feces or uterine discharges, be infected when drawn from cows with open lesions in the respiratory and digestive tracts or organs of reproduction. 4. Tubercle bacilli are not as a rule present in the milk of cows that react to tuberculin and which on a careful physi- cal examination exhibit no evidence of disease. 5. The number of tubercle bacilli in market milk would be greatly reduced, and possibly entirely eliminated, by having frequent and thorough physical examinations of the dairy cows and the removal of all individuals showing evi- dence of disease. [I wish to express my thanks to Dr. W. H. Boynton, Prof. E. G. Peterson and Mr. R. R. Bolton for valuable assistance in carrying on this investigation.] REFERENCES. Moore and Boynton. N.Y. State Dept. Health, 29th Annual Report, i, 1908, 567. Moore. Report of the N.Y. State Veterinary College at Cornell University, 19 10, 46. Peterson. Report of the N.Y. State Veterinary College at Cornell University, 1910, 60. Reynolds and Beebe. Dissemination of tuberculosis by the manure of infected cattle. Bulletin No. 103, Agric. Exp. Sta., Univ. of Minnesota, 1907. Reichel and Deubler. An examination of the feces of forty cattle for tubercle bacilli and conclusions. Journal of Medical Research, xxiv, i9"5 5- Schroeder and Mohler. The tuberculin test with hogs, and some methods of their infection with tuberculosis. Bulletin 88, Bureau of Animal Industry, U.S. Dept. of Agric, igo6. Schroeder and Cotton. Danger from tubercle bacilli in the environ- ment of tuberculous cattle. Bulletin No. 99, Bureau of Animal Industry, U.S. Dept. of Agric, 1907. Schroeder. The unsuspected but dangerously tuberculous cow. Cir- cular 118, U.S. Bureau of Animal Industry, 1907. The Tournal of Medical Research, Vol. XXIV., No. 3, June, igii.