336 BUILDINGS, SANITATION, AND DISEASES 



striking contrast are the hogs slaughtered at three cities in one 

 of the leading dairy states, where there is a large number of 

 co-operative creameries and the raw skim-milk is fed." 



" Buyers for packing-houses are learning from bitter ex- 

 perience to avoid sections of certain states, and two firms will 

 not buy hogs from one state known to be badly infected. In 

 fact, many of the smaller packers in the Central West buy 

 subject to post-mortem inspection, as a measure of self-pro- 

 tection." 



" It is known beyond all doubt that the majority of tuber- 

 culous hogs are produced by the following causes : 



" 1. Feeding raw milk and slime from creameries. 



" 2. Feeding hand-separated milk from tuberculous cows. 



" 3. Feeding behind tuberculous cattle. 



" 4. Feeding tuberculous carcasses. 



" 5. Feeding slaughter-house offal. 



" The danger of feeding hogs behind tuberculous cattle lies 

 in the fact that such cattle discharge enormous numbers of 

 tuberculosis germs in their faeces.' 7 



Symptoms Obscure. The quotations given show the im- 

 portance of this disease., and the need for the farmer to be on 

 his guard. It is a contagious disease and must be treated as 

 such. The symptoms are not well marked, and a hog may be 

 badly diseased and show practically no clinical symptoms. If 

 the lungs are affected, the hog usually has a cough, and, if the 

 digestive organs are badly affected, there is generally indiges- 

 tion, and general lack of thrift; but similar symptoms may 

 show themselves with other diseases, and it requires a great 

 deal of experience to diagnose the disease with certainty. 



Treatment is entirely preventive. Since the disease is 

 usually communicated to hogs through their feed, it is necos- 



