TUBERCULOSIS. 429 



In the case of very valuable purebred animals and under excep- 

 tional circumstances it may be more advantageous to retain the react- 

 ing animals which are in good condition in order to breed from them 

 and in that manner avoid the excessive loss which would follow from 

 their immediate slaughter. This may be done if proper precautions 

 are adopted. 



The disposal of reactors depends upon the State laws and live- 

 stock regulations of the State in which the herd belongs. If this 

 policy is followed it should be attempted only after careful study of 

 the plan known as the Bang method of controlling tuberculosis. The 

 live-stock officials of the State should be frequently consulted and 

 their advice followed ; otherwise failure will surely ensue. The plan 

 necessitates considerable trouble and is not recommended except un- 

 der the circumstances mentioned. 



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 bod3^ 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- 

 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 in the blood and Ij^mph and can 

 they be detected in the muscular tissue ? 



