Section V. 

 DISEASES OF THE STOMACH AND INTESTINES. 



1. Vomiting. Vomitus. 



{Erhrechen [German] ; Eniesis.) 



Etiology. Vomiting is produced by an irritation in the 

 vomiting center of the central nervous system, the stimulus 

 acting upon certain parts of the nervous system directly or by 

 reflex irritation from a spot in the gastro-intestinal tract or 

 other portion of the body. Hence vomiting may be part of the 

 clinical picture of a variety of diseases, but it is most frequent 

 in the course of certain diseases of the stomach or of the small 

 intestines. 



One of the most frequent causes of vomiting is overloading 

 of the stomach. For this reason vomiting very frequently occurs 

 among dogs and swine, but it is not rare in ruminants (in con- 

 sequence of overfilling of the paunch and of bloating) and also 

 occurs in horses. Irritation of the gastric mucosa is the cause 

 of vomiting if the latter occurs after the ingestion of irritant 

 acrid feed (cattle sometimes vomit after the ingestion of al- 

 falfa), after the administration of acrid or irritant medicines 

 (emetics) and also during catarrhal or inflammatory diseases of 

 the gastric mucosa (distemper, parasites in the stomach, hog 

 erysipelas, ulcer, etc.). 



Deli observed in one eomnumity an enzootic occurrence of vomiting among 

 horses; both at rest and in motion the animals vomited repeatedly a watery fluid. 

 According to the opinion of the author, the ingestion of muddy water had caused 

 a relaxation of the cardia with subsequent mild vomiting. 



Of the various diseases of the intestines, obstruction of the 

 intestines especially leads to vomiting. In such a case anti- 

 peristalsis often occurs, which propels the contents of the intes- 

 tines toward the stomach ; the vomitus, therefore, is mixed with 

 intestinal contents. In displacements of the intestines and in 

 acute peritonitis the emetic stimulus may originate in the peri- 

 toneum. 



That the internal genital organs may furnish the exciting 

 stimulus for vomiting has never been shown in veterinary 

 science. Irritation of the buccal mucosa occasionally also 



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