Investigations concerning bovine tuberculosis : with special reference to diagnosis and prevention / conducted under the direction of D.E. Salmon.
- Date:
- 1894
Licence: Public Domain Mark
Credit: Investigations concerning bovine tuberculosis : with special reference to diagnosis and prevention / conducted under the direction of D.E. Salmon. Source: Wellcome Collection.
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![tenderness at the seat of injection, tliey have apparently no practical significance. So far as it was possible to observe, no unfavorable condition was produced in any animal by the tuberculin injections. In regard to this matter most observers are agreed.* A reduction in the milk secretion, if this occurred, was only tempo- rary, and too small in amount to attract attention in a large herd of which only a comparatively small number of cattle were under theinilu- ence of the tuberculin at one time. It is reasonable to suppose that the quantity of milk from cattle affected by a loss of appetite was slightly diminished in consequence of the smaller amount of food consumed. The reduction in the milk secretion observed in cattle tested with tuber- culin in Karlsruhe and Mannheim was attributed to this cause and to the disturbance of the animal while undergoing the test.t A decided reduction in the milk secretion was observed in cattle tested in Berlin, but the specific gravity of the milk remained unaffected.f § * Deutsche Zeitschrift f. Thiermed, xviii (1891), p. 97. Arbeiten a. d. Kaiserlicben Gesuudiieitsamte, viii (1892), p, 86. iIbid.,^.S6. ^ The amount of milk secreted by 65 to 70 cows iu a herd of 134 cattle which wore injected with tuberculin in Virginia was 800 pounds the day before and 750 pounds the day after the injection. In 71 per cent of the herd the injection was followed by a reaction. Unfortunately this herd could not be kept under observation a longer time than the tuberculin test actually required to determine the number of animals affected with tuberculosis, and hence no exact data could be secured on the amount of milk secreted by the cows during the first eight to ten days after the injection. On this last point the manager of the herd informs me that a reduction in the amount of milk commenced the day after the injection, that it was progressive during several days, and reached its climax the fourth or fifth day, and that the daily amount of milk then increased again until it reached its normal about the tenth day. In this connection the following table may be of interest. It includes 6 cows, each of which was injected with 0.3 cc. of tuberculin K, The amount of reaction (the difference between the highest temperature the day before and the day after the injection) is given in degrees F., and the amount of milk in jiounds the day before and after the injection. lieduction No. of cow. Amount of Milk before Milk after in milk reaction. injection. injection. after injec tion. 1 2.9 16.1 15. 0 1.1 2 0. 3 27.1 27.8 -0.7 3 2.8 17.7 16.2 1.5 4 4.6 22.5 • 17.1 5.4 5 2.3 17. 3 17. ] 0.2 6 1.9 30.9 29.1 1.8 Total 131.6 122. 3 9.3 Of the above cows all, except No, 5, had calved within the last two to five months, and were not pregnant. No. 5 bad calved eight months i)rcvious to the test and was five months advanced in pregnancy. In another herd in Virginia, in which 15 cattle were injected with tuberculin, and 70 per cent of the milk cows reacteil, a marked reduction in the amount of milk yield during the first few days after the injection was reported.—E. C. S.](https://iiif.wellcomecollection.org/image/b21783111_0025.jp2/full/800%2C/0/default.jpg)
