24 



crumble under the pressure thrown upon them. If the tuber- 

 cle is deposited in liver, pancreas, or kidneys, there are 

 symptoms of disease of these respective organs. Recoveries 

 sometimes ensue in strong subjects, but more frequently the 

 disease progresses to a fatal issue." 



Causes. 



* '<The insidious nature of tuberculosis has perhaps had 

 much to do with the comparative slowness with which pro- 

 fessional and public attention has been directed to it, but the 

 strides which it has made and the hold which it has gained 

 on our stock render it one of the most, if not the most, 

 important questions affecting the future well-being of the 

 bovine species." Mr. Walley further states that in his opin- 

 ion this increase is to be explained by multiplied consan- 

 guinity, by artificial feeding and manuring, by excessive forc- 

 ing, and by early and over breeding. Walley gives as among 

 the predisposing causes of this .disease, the following : (1) 

 Species of animals, (2) hereditary tendency, (3) breeding in- 

 and-in, (4) breed, (5) early, late, and over breeding, ((3) 

 physical conformation, (7) climate and locality, (8) debility. 



f " Close, badly aired buildings are among the most 

 prolific causes of the disease, as are also changes to a colder 

 climate, to a cold, exposed locality, or from a dry to a low, 

 damp, undrained region. Finally, any cause which tends to 

 wear out the general health tends to tuberculosis in a predis- 

 posed subject." 



% " But the infectious principle, the cause, of the disease 

 was entirely unknown until the announcement of Robert 

 Koch, of Berlin, who, after a long series of experiments, 

 proved beyond a shadow of a doubt that tuberculosis is due 

 to the activity of a minute organism included among the 

 bacteria; in other words, that the ' bacillus of tuberculosis' 

 is the cause of this disease in all its forms, no matter where 

 they occur. It is produced by this organism. It is never 



* " Four Bovine Scourges," Thomas "Walley, M. R. C. V. S. 

 t "The Farmer's Veterinary Adviser," Prof. James Law, 



+ Dr. H. C. Ernst before the Legislative Committee on Public Health, February, 

 189L 



