52 



SWINE DISEASES 



grayish color are readily visible on the serous coat of the 

 intestine. The thorn of the worm is found to have 

 penetrated the mucosa, and thus permits of infection 

 which results in the production of an inflammatory zone. 

 The parasites may become detached, the lesions pro- 

 duced having healed by the formation of cicatricial 



Yig. 3. GIGANTORHYNCHUS HIRUDINACEUS. 



tissue, which is usually easily recognized. Not infre- 

 quently the head of the parasite bores through the 

 entire intestinal wall and occasions general peritonitis. 

 Symptoms. The usual symptoms consist of di- 

 gestive disturbance the magnitude of which willjiepend 

 upon the extent of infestation. The infested animal 

 usually gives evidence of pain, as the parasite lacerates 



