530 Veterinary Medicine. 



I should add that isolated superficial tubercles may often be 

 excised to advaDtage, and the part dressed antiseptically. 



It is only in exceptional cases, however, that one is warranted 

 in preserving and running the danger of spreading the tubercle 

 bacillus for the advantage that can be secured to individual ani- 

 mals from treatment. 



EXTINCTION OF TUBERCULOSIS IN CATTLE. 



As cattle are the great propagators of tuberculosis on the 

 farm, the question of extinction necessarily centers around this 

 race. As in all other dangerous infections, the most prompt and 

 successful method would be in the time honored one of destroying 

 the infected and thoroughly disinfecting all their products. The 

 only barrier to success in such a case would be the conveyance of 

 infection anew from man to cattle after the herd had been puri- 

 fied. The demonstration that cattle are less susceptible to in- 

 fection by the human sputa than many had supposed does away 

 largely with this objection, as in a generally purified bovine race, 

 the few primary cases contracted from man could be easily taken 

 care of. Then, if tuberculous persons were interdicted from at- 

 tendance on cattle, the danger in this direction would become 

 very nearly a negligible quantity. 



There remains the question of expense and many honestly 

 consider this as absolutely prohibitory. The estimate of 5 per 

 cent, of our 68,000,000 head to be killed and paid for at $25 per 

 head, would be $85,000,000. But there is no necessity for this. 

 Our fat steers at the packing houses are tuberculous only to the 

 extent of 0.02 per cent., speaking well for their dams and nurses. 

 The estimate of 5 per cent, based upon the testing of those few 

 herds that have been taken because they were already known to 

 be tuberculous, is unquestionably far above the actual ratio for 

 the United States. It may apply to dairy cattle in some infected 

 districts, but, for the bovive race of the whole country, it is ab- 

 surdly high. If we had 10, 20 or 50 per cent, infected, as in 

 some countries of Europe, the objection of expense might be a 

 formidable one, but when the ratio of the infected is but 2 : loooo, 

 we have every encouragement on the score of expense to enter 

 on a campaign of extinction. But again, we do not need to deal 

 with 68,000,000 cattle as we can omit the steers which are so 



