270 SWINE 



SOURCE OF INFECTION. 



As already stated the disease is caused by the tubercle 

 bacilli. The question then naturally comes up, Whence 

 comes the germ that causes this disease in swine? It is 

 usually caused by the pig eating feed that is affected with 

 tuberculosis. Various causes may be cited as follows : 



Skim Milk. — Milk from tuberculous cows may contain 

 the tubercle bacilli ; while all tuberculous cows do not 

 give tuberculous milk, it is said that as high as twenty per 

 cent of them may have the disease germ in the milk. If 

 this is fed to pigs it will naturally cause the disease, as a 

 pig is very susceptible to germs of this nature. In order 

 to prevent this cause of infection the dairy herd should 

 be thoroughly freed from tuberculous individuals, or else 

 the milk should be sterilized. This may be done by boil- 

 ing the milk before it is fed. Pasteurizing also destroys 

 most of the germs. The latter consists in keeping the 

 milk at 60° C. or 140° F. for twenty minutes. 



Country Slaughter Houses. — These slaughter houses 

 are very often responsible for tuberculosis in swine. Such 

 places usually have a drove of pigs present to consume 

 the offal which otherwise would be wasted. Eating the 

 entrails from the bodies of tuberculous cattle that are 

 slaughtered and thrown out to the hogs, they will be 

 pretty sure to become affected with tuberculosis. This 

 means of infection is usually very great because often cat- 

 tle that are not thrifty are sold and frequently are sold to 

 ■country butchers, because they are sold at unusual times. 

 Furthermore, these places do not have government in- 

 spectors, hence all the animals slaughtered at such places 

 pass into consumptive channels which is dangerous to the 

 hog eating the offal in a raw state. 



