70 MICHIGAN ACADEMY OF SCIENCE. 



A summary of results of an experiment in Denmark reported by 

 Professor Bang is as follows: 



*'Wliole herd of 208 (mih-li cows) tested in spring, 1892, reacted [to 

 tuberculin test] 80 per cent." The seventy healthy cow's, that did not 

 react, were then separated from the infected animals. Whether or 

 not there was any tliorough disinfection of the premises and pastures 

 to be occupied by the healthy cows, I am not informed; but the further 

 tests spring and autumn for three years resulted as follows: 



Sound herd of 70 tested in autumn, 1892, reacted 10 per cent. 

 Sound herd of 108 tested in spring, 1893, reacted 10 per cent. 

 Sound herd of 107 tested in autumn, 1893, reacted 1 per cent. 

 Sound herd of 122 tested in spring, 1891, reacted 1.6 per cent. 

 Sound herd of 119 tested in autumn, 1894, reacted 1 per cent. 

 Sound herd of 136 tested in spring, 1895, reacted 2 per cent. 



''Here is a. large herd in which 80 per cent of the milch cows reacted. 

 * * * After separation, the test w^as carried out twice a year, and 

 the stock augmented, chiefly by breeding. The sound herd remained 

 practically sound (only 1 or 2 per cent reacting at each test), and at 

 the end of three years the sound herd is about double in size. — Sanitari/ 

 Journal."* 



Separation of healthy animals from infected animals would not be 

 sufficient to prevent the disease from attacking the healthy animals, if 

 the timothy bacillus, or any other microorganism not parasitic on 

 animals could cause tuberculosis. 



The University of Wisconsin Agricultural Experiment Station Bulle- 

 tin No. 78, for August, 1899, is ''The History of a Tuberculous Herd of 

 Cows." It is an extremely valuable document, tending to prove: 1, that 

 tuberculosis is not inherited by calves of tuberculous cows; 2, that it is 

 communicable; and 3, that calves from tuberculous cows if fed on un- 

 infected milk, and kept away from infected animals, do not contract 

 tuberculosis. Briefly that i)art of the history which I wish to present 

 to you is as follows: In 1891 a farmer bought some blooded stock, 

 whereby it appeared that tuberculosis was introduced into his herd. 

 In 1895 tuberculin tests revealed the fact that 13 out of 16 mature 

 aniuuils had tuberculosis. Every breeding animal in his herd except 

 two were tuberculous. The question arose whether it was possible to 

 build up a healthy herd of the blooded stock without destroying the 

 tuberculous animals. The animals were separated into two herds, one 

 infected, one uninfected. The barn was cleared of all litter, disinfected, 

 a partition of one thickness of boards was made across the barn, the 

 infected animals were all kept in one end, the uninfected in the other 

 end of the barn. The two herds were not pastured in the same fields. 

 Although kept on the same farm where ]»reviously the disease had 

 spread, in the same barn, separated, however, by a partition, and sub- 

 ject to the same food and climatic conditions as before, there was no 

 further spread of the disease after the separation of the infected from 

 the uninfected; thus proving conclusively that the disease was not ])re- 

 viously spread by any timothy bacillus, or by any other thing whatever 

 except directly or indirectly from the infected animals. 



* Ohio Sanitary Bulletin, Vol. 1, 1897, page 89. 



