DISEASES OF POULTRY. 101 



lual parasites, viz., the protozoa. The varieties of 

 protozoa which cause enteritis are generallj' spoken oi 

 3iS psorospcr)?is QiwA the disease which they produce is 

 known as psorospcr)?iosis or psorospcDiiic enteritis. 

 There are two species of psorosperms which have been 

 found to produce inflammation in the intestines of 

 fowls: The liiiiicria diibia {Gregarijia aviuui iiitestin- 

 alis) and the Locddium toielluin. As the symptoms, 

 the appearance of the intestines, and the treatment 

 varies considerably from bacterial enteritis, it is neces- 

 sary to devote a special article to the psorospermic 

 form. 



Causation. — These parasites, probably in the con- 

 dition of spores, are taken intoihe digestive tube with 

 the food or drink. They multiply along the course of 

 the intestine, penetrate the mucous membrane, pro- 

 duce irritation and set up a series of changes in the 

 tissues which very seriously affect the functions of the 

 invaded organs. 



The Iiitneria dubia mutiplies also in the con- 

 nective tissue beneath the mucous membrane^ form- 

 ing small cysts, seen as whitish points, which are 

 found filled with its spores. The inflammation may 

 extend even to the peritoneal coat of the intestine, thus 

 producing a complication of peritonitis with en- 

 teritis. The lesions resemljle, more or less, those of 

 diphtheria and tuberculosis, and as the liver and lungs 

 are often invaded we can understand wh}' the disease 

 has been called tubcrc2ilo-diplitlieria by Megnin, Cornil 

 and others. 



The Coecidiiini tenellum is generally found localized 

 in the caeca. It multiplies in the mucous membrane, 

 producing whitish patches, denuded surfaces, and ul- 

 cers, and causes a very intense inflammation. 



