428 DISEASES OP CATTLE. 



excessive loss which would follow from their immediate slaughter. 

 This may be done safely if proper precautions are adopted. Tho 

 healthy animals should be separated from the diseased ones, and the 

 stable in which the diseased animals have been should be frequently 

 disinfected. When calves are dropped by the tuberculous cows they 

 should be immediately removed, or at least not allowed to drink the 

 mother's milk more than once or twice, and after that fed upon the 

 milk of healthy cows. The milk from the animals which have 

 reacted should not be used until after it has been boiled and the 

 tubercle bacilli thus destroyed. The younger animals which are 

 raised from tuberculous dams should be tested when they are about 

 6 months old, and all those which react should be immediately 

 slaughtered. It has been found that by following the i)lan sug- 

 gested above not more than 1 or 2 per cent of the calves develop 

 tuberculosis. It is, of course, some trouble to follow this method, 

 but it enables the owner of a pure-bred herd to retain the strains 

 of blood which he has been breeding and gradually to eliminate the 

 disease. At the end of six or eight j^ears he should have a herd of 

 cattle free from tuberculosis and be prepared to destroy all those 

 which have reacted. 



BOVINE TUBERCULOSIS AND THE PUBLIC HEALTH. 



The increasing amount of evidence pointing to the identity of 

 human and animal tuberculosis, combined with the extraordinary 

 mortality of human beings from this disease, often amounting to 10 

 to 14 per cent, has raised the question in all civilized countries as 

 to how far animal, and especially bovine, tuberculosis is 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 conclu- 

 sion. 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 either through the 

 meat, the milk, the butter, the cheese, or through all these products 

 that the virus enters the human body. The question has thus nar- 

 rowed itself down to the food products furnished by cattle. 



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

 ti-ies 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 



