26 Bulletin 150. 



EXTINCTION OF TQBERCULOSIS WITHOUT THE 



TUBERCULIN TEST. 



As successful examples of this I may quote from my own per- 

 sonal experience. 



I St. A herd of about 200 head belonging to the Willard Asy- 

 lum had become badly affected with tuberculosis and on physi- 

 cal examination, without the use of tuberculin, I condemned 

 about 50 per cent. These were accordingly destroyed and new 

 barns and yards were constructed at some distance from the 

 others and filled with cows selected from the most healthy herds 

 available. These were bred to healthy bulls and a new herd 

 gradually built up. Meanwhile the remaining 50 per cent of the 

 original herd were gradually slaughtered, and like the original 

 half of the herd were found to be tuberculous without a single 

 exception. The original barn was thoroughly cleaned, repeat- 

 edly disinfected with chloride of zinc and with its cleansed and 

 disinfected 3^ards was left unoccupied for an entire year. The 

 fields on which the original herd had pastured were used for 

 other purposes than pasture for two full 3^ears. The new herd 

 was carefully watched and any cow which contracted a cough or 

 showed especially poor health was at once separated from the 

 herd and disposed of. This treatment of the new herd was kept 

 up for over twelve 3^ears, and in the middle of December, 1897, 

 I subjected the mature animals of the herd to the tuberculin 

 test, and found not a single case of tuberculosis. I have never 

 before subjected an untested herd of this size to the action of 

 tuberculin without finding a considerable percentage of cases of 

 tuberculosis. The splendid showing is highly instructive as to 

 the high value of intelligent management even without the aid 

 of tuberculin. Here a large herd was maintained under the 

 same conditions of food, milking and housing (even in the same 

 barns) as the former herd which became universally tuberculous, 

 and, even under the crucial test of the tuberculin, furnished 

 not a single case of tuberculosis. The only difference is that 

 with the present herd intelligent measures were taken to exclude 

 the germ of the tuberculosis. The case is all the more striking 

 that some of the most important precautions against the spread 



