TUBERCULOSIS. 355 



cattle to man. If, on the other hand, it should prove that the 

 human bacillus is especially dangerous for man, while the 

 bovine variety is slightly virulent for man, the danger of 

 human infection from cattle would be slight. A positive de- 

 cision between these two views cannot at present be reached. 

 Prof. Koch has recently announced the conclusion that the 

 bovine bacillus is different from the human bacillus, and that 

 the disease consequently cannot pass from cattle to man. 



BOVINE TUBERCULOSIS. 



To the agriculturist the most important phase of this prob- 

 lem is its relation to cattle. It is true that in recent years, 

 owing largely to the feeding of swine with creamery refuse, the 

 disease is coming to be somewhat common among swine. 

 But it is among cattle that the trouble is most widely distributed 

 and of the most serious import. In cattle it attacks chiefly the 

 glands of the neck, the glands of the intestinal tract, and the 

 lungs. It may, however, be found almost anywhere. It may be 

 located in the udder, and in these cases the milk of the animal 

 becomes a source of danger to the animal drinking it. For- 

 tunately, the number of cases of udder disease is comparatively 

 small. It is impossible to give any exact statistics, but I per 

 cent, is probably not far from correct. In cattle it rarely at- 

 tacks the bones, joints or muscles, and is almost always 

 confined to the glands, lungs and intestinal tract. 



In cattle, as in man, it has a variable course. It may be 

 localized in a small gland and produce no disturbance what- 

 ever. Such cases are only to be detected by tuberculin, and 

 some of them are known to recover completely. It may, 

 however, spread from such centers into other glands, and from 

 these spread still more widely, until the whole body is infected 

 and a fatal result occurs, or the animal is condemned to 

 slaughter. The disease may take several years to run its 

 course, the animals apparently remaining for years without 



