FARM ANIMALS 237 



be an important cause. Many experiments in 

 which large quantities of animal meal have been 

 used have shown that these foods have no tendency 

 to cause sows to eat their pigs. Apparently, 

 one of the chief causes of this trouble is found 

 in the inflammation of the udder or soreness due 

 to the biting of the pigs or to the bruising of the 

 organ upon sticks or other obstacles. At any 

 rate, the habit has often been checked in appar- 

 ently vicious sows by rubbing the udder with a 

 cocaine solution containing five per cent, of cocaine 

 and lanolin or some other greasy material. 



