Tuberculosis in Cattle. 23 



diiced no appreciable change in the general health as evidenced 

 by temperature, breathing, pulse, 3'ield of milk or quality of 

 milk. I feel accordingly that I can speak with the greatest con- 

 fidence as to the entire harmlessness of the tuberculin test on a 

 sound animal. 



That it rouses into a temporary- activity the tuberculosis already 

 existing in the unsound animal is true. Were it not so it would 

 be useless as a diagnostic agent. But if the state stands ready to 

 destroy and pay for the diseased, there can be no possible 

 objection to the temporary aggravation which leads to the purifi- 

 cation of the herd. 



MEASURES FOR THE ERADICATION OF 



TUBERCULOSIS. 



For the complete eradication of tuberculosis from a herd or 

 country the first and main consideration is the absolute separation 

 of the sick animal and all its products from the health}-. This 

 is fundamental in dealing with all infectious diseases, and if it 

 could be applied would reduce all contagious disorders to the 

 condition of simple sporadic ones. Plagues would cease to be 

 plagues, and the infecting disease would cease like any other 

 affection with the first individual case. The plagues of men follow 

 the great movements of men — pilgrimages, armies, trade. The 

 animal plagues prevail continuously in unfenced territories (Asia, 

 Central Europe, Australia, Tasmania, New Zealand, South 

 Africa), and follow the tract of armies and the channels of com- 

 merce. Stop the great accummulations and intermingling of 

 animals and we arrest the general diffusion of a plague and 

 reduce it to the comparativeh^ insignificant importance of some 

 common disease. 



Exceptional cases like anthrax and blackquarter in which the 

 germ is maintained for 3-ears in the soil, are only apparent 

 exceptions to this fundamental principle, as whenever the germ 

 can thus be carried in soil or water the separation of sick and 

 their products from the healthy is incomplete. 



In applying this principle to tuberculosis we meet with the 

 drawback that a great variety of animals of different genera are 



