72 THE MILK SITUATION IN THE DISTRICT OF COLUMBIA. 



While the effect of the introduction of the tuberculin test on the 

 price of cattle is problematical, it may be conservatively estimated 

 with some degree of accuracy that the effect of the enforcement of the 

 test gradually, as proposed, or only so far as applies to cattle furnish- 

 ing milk to the District of Columbia, will be quite inconsiderable 

 and will be counterbalanced by the increased value to be derived by 

 the farmer for his stock already on hand and by the additional price 

 received by him for his milk. 



COMMUNICABILITY OF HUMAN TUBERCULOSIS FROM BOVINE SOURCES. 



Much attention is being devoted at the present time, by segrega- 

 tion and otherwise, to minimizing the danger among human beings 

 of infection with tuberculosis from bovine sources, with the hope 

 of ultimately eradicating the disease among humans. The prudence 

 of removing this possible source of infection by expelling from exist- 

 ing herds such animals as are shown to be affected with tuberculosis 

 in even its preliminary stages must appeal with force to every well- 

 minded person. The elimination of the disease from among cattle 

 by rigorous insistence upon segregation of tuberculous individuals is 

 obviously more easy of accomplishment than among human beings, 

 where our sympathy and commiseration leads us to ignore many 

 well-established sanitary precautions for preventing contagion. 



It should be understood that the movement which is now progress- 

 ing so successfully to oust all diseased animals from herds of milch 

 cows, and indeed of neat cattle, is not only substantially in the inter- 

 est of the public health, but will be found to be of decided advantage 

 from an economic standpoint to the herd owner; for tuberculosis 

 among animals, encouraged by conditions existing up to the present 

 time, is not only increasing with alarming rapidity, often extending 

 to every single animal in a herd and decimating its numbers with 

 frequency, but experience shows that the amount and quality of milk 

 derived from diseased animals is inferior to that which may be rea- 

 sonably expected from healthy cattle maintained under proper sani- 

 tary conditions. When it is estimated that 25 per cent of all cows 

 furnishing milk to the District of Columbia are infected with tuber- 

 culosis the importance of proceeding at once with firmness to the 

 elimination of diseased cattle from such herds will be promptly 

 recognized. 



There has been considerable dissension among the ranks of phy- 

 sicians and sanitarians as to the communicability of tuberculosis to 

 human beings from tuberculous animals, either through the medium 

 of milk or the use of their flesh for human food, and numerous 

 investigations have been in progress with a view to establishing the 

 facts relating to this important subject. So eminent an authority as 

 Prof. Eobert Koch, who first discovered the primary cause of tuber- 

 culosis, and who first presented tuberculin to the world, while ac- 

 companying the announcement of the latter triumph with the 

 statement that he considered the disease identical in both man and 

 cattle (which view was almost universally accepted by scientists as 

 well as the general public), subsequently announced in 1901 that he 

 regarded the disease as different in man and in cattle, and that there 

 was no practicable need for prohibiting the use of the products of 

 tuberculous animals for human food. This latter statement gave 



