420 THE MANAiJEilENT AND FEEDING OF CATTLE 



it, Bacillus tuberculosis, is always present in the system 

 of infected animals. It may affect any organ or tissue 

 of the body, but is more frequently found in the lungs 

 and intestines. Especially when the udder is diseased 

 the germs are present in the milk. A post mortem will 

 usually reveal diseased tissue in some part of the organ- 

 ization. Nodules, usually called tubercles, will be found 

 in or upon the parts attacked. These vary in size from 

 a pin head to a good-sized marble. Tubercles contain a 

 cheesy or gritty substance, which, in many instances, has 

 turned to pus, usually of thick consistency. 



The symptoms which indicate the presence of tuber- 

 culosis, especially in the early stages of the disease, are 

 frequently elusive, so much so that in the absence of the 

 tuberculin test the most skillful veterinarian may be 

 unable to say whether the germs are or are not present 

 in a given instance. In the summer of 1905 the author 

 was shown a collection of high-bred Shorthorn cattle 

 numbering more than 30 animals, every one of which 

 was high fleshed and appeared to be in finest bloom, and 

 yet, in every instance, the tuberculin test had shown 

 them to be tuberculous. These had been sifted out from 

 many others, bought to secure representatives of certain 

 families of Scotch cattle. The owner, Hon. W. C. 

 Edwards of Rockland, Ontario, Canada, was raising 

 calves from them by what is known as the Bang system. 

 (See page 425.) 



In some instances the germs may be present for 

 years, and yet the animals will live and thrive, but, in 

 many instances, there comes a sudden breaking down, of 

 which it may be said that they literally fall to pieces. 

 When the lungs are seriously afifected, a chronic cough 

 is likely to be present which is stirred into action by 

 sudden exposure to cold air or by exertion which calls 

 for much effort. When the intestines and mesenteric 

 glands are seriously affected, chronic diarrhoea is pres- 

 ent. When the lungs or the intestines are thus seri- 



