118 SWINE PRACTICE 



intestine, though they may occur in the large intestine and even in 

 the stomach. They attach themselves to the mucous membrane by 

 means of papillae or membranous teeth, and produce irritation to 

 the mucous membrane as well as provide an avenue of entrance 

 for a variety of bacteria whicli may produce inflammatory lesions 

 and even necrosis and ulceration. The entire mucous membrane 

 adjacent to the parasites is affected by a catarrhal inflammation. 



Fig. 25. Ascaris Suum. 



Similar disturbances are observed in the mucous membrane of the 

 hepatic duct when it is infested. The worms may form a mass that 

 completely obstructs the intestine, resulting in an engorgement of 

 the intestine anteriorly to the obstruction. Occasionally the intestine 

 may be perforated and the offending ascarids found protruding into 

 the peritoneal cavity, or they may pass through the intestinal wall 

 and some of the intestinal content, and, escaping into the peritoneal 

 cavity, produce a general peritonitis. 

 Symptoms. — Infestation with a limited number of ascarids prob- 



