CHAPTER XXXIV. 

 COMMON DISEASES OF SWINE. 



HOG CHOLERA ( SWINE FEVER). 



THIS highly infectious disease is due to a germ, and causes 

 a loss of many millions of dollars annually in the United States. 

 It causes an inflammation and ulceration of the "stomach and 

 intestines, enlargement and inflammation of the lymphatic 

 glands, and various other disturbances. The most characteristic 

 lesions of the disease are inflamed areas on the lining mem- 

 brane of the intestines and stomach, which eventually change 

 into raised ulcers, circular in outline. (Figs 90 and 91.) 



Symptoms. The hog usually goes off by itself and lies 

 in a cool place. The back is arched, the hind parts appear 

 stiff, causing the hog to stagger and cross the hind legs as it 

 walks. There is a watery secretion from the eyelids, which later 

 becomes thicker in character, causing the lids to adhere. Owing 

 to increased secretions from the skin, dirt adheres to it, giving 

 the animal a dirty appearance. Alternate diarrhoea and con- 

 stipation is common, and the diarrhoeal discharge is thin and 

 watery, and sometimes mixed with blood. (Fig. 92. ) 



Acute cases usually terminate in death in from two days to 

 two weeks, but sometimes death occurs before the symptoms 

 become well marked. 



In the subacute or mild form, the symptoms may escape 

 notice, but there is usually a slight fever, with loss of appetite, 

 constipation, and diarrhoea. The pig generally recovers in a 

 few days. 



The disease is said to be chronic when it lasts for a con- 



(327) 



