DISEASES OF CATTLE. 



bestowed upon the breeding, the surroundings, and the food of the ani- 

 mal, so that the latter may be put into a condition to resist infection 

 even when exposed to it. If the method of diagnosis referred to above 

 proves a success, this should be used whenever strange cattle are intro- 

 duced into a herd. A rigid exclusion of tuberculous animals, if this 

 were possible, would be all that is necessary to prevent the appearance 

 of the disease, provided cattle are not infected by consumptive per- 

 sons and animals, which we can not consider as impossible at the pres- 

 ent time. 



Tuberculosis in cattle must also be considered as bearing upon tuber- 

 culosis of other domesticated animals, particularly swine. In Europe 

 this disease is not so uncommon among swine, while in our own coun- 

 try it seems to be practically unknown. The reason for its existence in 

 Europe may be looked for in the feeding of pigs with whey in dairies, 

 with the offal of the abattoirs and the household refuse generally. If 

 tuberculosis is common among cattle it is likely to be transmitted to 

 swine kept in this way. There is, however, still some confusion of tuber- 

 culosis with other swine diseases, and it may be that the statistics are 

 much too high. 



The carcasses of animals which have died of tuberculosis should be 

 bulled deeply, so that they can not be eaten by other animals. This is 

 likewise true of all organs or tissues of slaughtered animals containing 

 tubercles. These should never be fed to other animals, such as swine, 

 dogs, and cats, and should either, be destroyed by fire or else deeply 

 buried. 



Bovine tuberculosis and the public health. The identity between hu- 

 man and animal tuberculosis, combined with the extraordinary mor- 

 tality of human beings from this disease, often amounting to from 10 to 14 

 per cent, has raised the question in all civilized countries as to how far 

 animal, and especially bovine, tuberculosis was to blame for this high 

 mortality. The medical and veterinary professions have approached 

 this problem with equal zeal, and much has come to light within recent 

 years which enables us to come to some conclusion. If this disease is 

 transmitted from animals to man, how does the transmission take place ? 

 As comparatively few people come in direct contact with tuberculous 

 cattle, it must be, if at all, either through the meat or the milk, or 

 through both, that the virus enters the human body. The question 

 has thus narrowed itself down to the food products furnished by cattle. 



It has become a very urgent question, especially in the poorer coun- 

 tries of Europe, whether all flesh from tuberculous animals is unfit for 

 human food. It is argued there that if it can be shown that in the 

 majority of cases of tuberculosis the bones and the muscular system are 

 free from infection, there is no reason why the meat should not be put 

 on sale under certain restrictions. The question may be resolved into 

 two divisions : (1) How frequently does the disease invade those parts 

 of the body which are used as food '? (2) "When the disease process is 

 manifestly restricted to the internal organs do tubercle bacilli circulate 



