344 Membranous Enteritis. 



17. Membranous Enteritis. Enteritis membranacea. 



(Socalled "DarmJirupp" [German] or Croupous enteritis; en- 



terite coueneuse, ou pseuclomemhraueuse ou muco- 



memhranense [Cadeac] [French].) 



Membranous enteritis is characterized by a peculiar, gener- 

 ally superficial, inflammatory process of the intestinal mucosa, 

 with the formation of pseudomembranes, which are composed 

 almost exclusively of mucus. 



Occurrence. This rather rare affection is observed most 

 frequently in cattle, according to Keilgaard quite frequently 

 in horses, rarely in sheep (Clavel, Lafosse). Among cattle, 

 young, well nourished and pregnant animals are affected prefer- 

 ably if after winter feeding they are pastured during cool 

 weather on luxuriant meadows. 



Etiology. The nature of the affection suggests infectious 

 material as its cause, while external influences, such as the in- 

 gestion of too cold water or the feed supply play a role as pre- 

 disposing factors. Nothing definite can be said as to the nature 

 of the supposed infectious agent. The disease has been observed 

 frequently after the ingestion of rotten potatoes or beets or of 

 absolutely fresh feed. 



Whether an occlusion of the intestines or the lack of peristalsis, due to intes- 

 tinal bacteria, may cause an accumulation of mucus cannot at present be decided. 

 It is, however, a fact that abundant thick masses of mucus collect in the rectum 

 of horses, similar to croupous membranes, if an internal occlusion, situated between 

 rectum and stomach, prevents peristalsis of the rectum. 



Anatomical Changes. As a rule the jejunum, cecum and 

 colon are uniformly changed; however, the small intestine or 

 on the other hand the large intestine alone may be the seat of 

 pathological changes. The intestinal contents are thin fluid and 

 dirty discolored, mixed with blood in grave cases and very fetid, 

 floating in it are found yellowish to brown, tough, elastic mem- 

 brane-like or tubular, cylindrical masses. Similar masses are 

 found adhering to the mucosa. The tubular or cylindrical de- 

 posits are usually from 1.5 to 3.5 feet long, but they may excep- 

 tionally be as long as 35 feet (Arnal). They are composed of 

 several layers, the membranous substance alternating with lay- 

 ers of darkly stained fecal matter. The intestinal mucosa shows 

 reddening in grave cases, also hemorrhages, it is somewhat 

 swollen. In the horse one usually finds changes only in short 

 portions of the large intestine and the pseudomembranes are 

 characterized by their small dimensions. 



The microscopic examination of the pseudomembranous deposits show the pres- 

 ence of numerous granules in an exceedingly fine reticulum (Gurlt). Weigert's fibrin 



