184 DISEASES OF SWINE 



ears and inside the forelegs, but there is seldom ever the wide- 

 spread discoloration of the skin that is seen with the acute cases. 



There is often some swelling of the ears and of the eyehds, but 

 it comes on more gradually than in the acute form of cholera, and 

 the swelling of the eyelids is seldom so marked as to cause blindness. 

 The swelling of the ears may become quite extensive, and the flies, 

 which are so plentiful around feed yards in summer time, attack 

 these swollen ears, and often result in the formation of large sores 

 which are covered over with scabs. I have seen numerous cases 

 where the entire inner surface of the ear was covered with a solid 

 mass of these sores, resulting from the bites of flies. 



After the disease has been working on the animal for a few days 

 the skin begins to pour out a dark-colored, sticky substance, which 

 sticks to the hair and serves to give the animal a very dirty, un- 

 thrifty appearance. 



As the disease progresses the animal loses flesh all the time 

 and gaunts up very rapidly. The flanks are sunken in and drawn 

 up and the back arched. This loss of flesh is not so rapid as in 

 the acute type, but it continues for several weeks throughout the 

 course of the disease, and results in a much more stunted appearing 

 animal than is seen in the acute form of the disease. Late in the 

 course of a case of chronic cholera the animal presents about as 

 runty an appearance as can be seen in any other disease to which 

 the hog is heir. 



Accompanying this loss in weight there is also a gradual loss 

 of strength and the development of muscular weakness. This has 

 the same result as in acute cholera. The animal becomes unable to 

 get about very well, and develops a wavering or staggering gait. 

 As in acute cholera, this weakness is most pronounced behind, and 

 in walking the animal has trouble to keep the hind legs from getting 

 crossed over in front of each other. The weakness and staggering 

 in the chronic form of cholera differs from that seen in the acute 

 cases, principally in that it is much slower in making its appear- 

 ance and is not well marked until the animal has been sick several 

 days or even a couple of weeks. 



When we try to make a close examination of the sick hog suffer- 

 ing from chronic cholera we find that there is a great amount of 

 tenderness, especially along the under surface of the belly. This 



