PARASITES IN THE STOMACH 163 



PARASITES IN THE STOMACH. 



The parasites that develop in the stomach of the dog are 

 very rare. The Spiroptera sanguinolenta, a small blood red 

 worm from 5 to 8 cm. long, is the most common. It forms 

 small, tumor-like masses in the mucosa. Occasionally the 

 larvae of the Gastrophilis intestinalis are found attached to the 

 mucous membrane. Ascarides and teenia commonly migrate 

 from the intestines. Tsenia are often found in the stomach 

 of the cat, the Taenia tseniseformis being the most common. 

 The Ollulanus tricuspis, however, is the only parasite proper 

 to the stomach of the cat. 



The adult Ollulanus tricuspis is about 1 mm. long and has 

 three points at the caudal extremity. The adult worm lives 

 in the gastric mucous membrane and when present in large 

 numbers, seriously interferes with the function of the mem- 

 brane. The embryos are quite large compared with the 

 adult parasite. Some of these embryos are passed with the 

 feces while others burrow through the walls of the intestines 

 and wander to various parts of their host, particularly the 

 pleura, diaphragm, liver and lung, w r here they form cysts. 

 When the free embryos are ingested by rodents they migrate 

 into the muscles and become encysted. It is probable that 

 their development is completed in the digestive canal of the 

 cat that feeds upon the infested rodent. 



Rabbits are chiefly infested with the Strongylus strigosus, 

 often found in large numbers, and give rise to a fatal anemia. 

 This parasite is 8 to 16 mm. long, body blood red, filiform 

 and transversely striated. 



The parasites most common in the anterior portion of the 

 digestive canal of birds are the Dispharagus spiralis, Disphar- 

 agus nasutus and the Trichosomum contortum. The dis- 

 pharagi are from 7 to 9 mm. long and the trichosome 12 to 

 17 mm. and are found either entirely embedded in the mucous 

 membrane or fixed in it by one extremity and the other 

 floating free in the cavity of the organ. The Trichosomum 

 contortum is frequently found in adjacent structures, but 

 is common in the walls of the esophagus. 



