TUBERCULOSIS 271 



Other Means of Infection. — Very often cattle that die 

 on the farm die of tuberculosis and are taken into the hog 

 lot where the carcass is consumed. In such a case tuber- 

 culosis is also started in a herd of swine. If tuberculous 

 cattle are being followed by swine in a pasture or feed lot, 

 the disease will also be transmitted. The droppings from 

 such cattle may be filled with the bacilli and the hogs 

 eating-them will naturally eat the germs and contract the 

 disease. Human tuberculosis even may be transmitted to 

 hogs in a case where the sputum is not properly taken 

 care of, but thrown into the slop bucket the contents of 

 which are finally taken to the hogs. 



If the disease is once present in a herd of swine it may 

 be transferred from one individual to others in the herd. 

 In order to be thus transmitted the disease must be suffi- 

 ciently far advanced that the hog will cough up the tuber- 

 cular material from his lungs in the form of sputum, which 

 would be responsible for starting the disease in other in- 

 dividuals, especially if they eat the sputum. The disease 

 is very readily transmitted from the sow to her litter. If 

 the sow has tuberculosis in a generalized form, and espe- 

 cially if she should have tuberculosis of the udder, the 

 disease will almost certainly be transmitted to the pigs 

 sucking her. If the disease is present in a herd, it is 

 usually found in quite a number of individuals — not be- 

 cause the disease is easily transmitted from one indi- 

 vidual to another, but because different individuals of the 

 herd contract the disease from the same source. 



DURATION OF. THE DISEASE. 



Tuberculosis works much more rapidly with swine than 

 it does with cattle. A pig, if affected when young, may 

 succumb to the disease within a few weeks. At other 



