164 CLINICAL DIAGNOSTICS. 



or even to constipation. Voluntary defecation is almost im- 

 possible when paralysis of the rectum exists, in such cases 

 the agitation of the body during locomotion causes the feces 

 to be passively discharged through the gaping anus. 



Involuntary evacuations of the bowels occur in cerebral 

 spasms and in paralysis or relaxation of the anus. The latter 

 is common in the course of severe diarrhoeas, here the semi- 

 liquid feces flow down on the legs. 



Defecation is painful in the course of painful inflamma- 

 tory conditions in the abdominal cavity (intestine, periton- 

 eum), diaphragm or abdominal walls. These conditions all 

 interfere with the normal contraction of the abdominal mus- 

 cles during the act of defecation. In dogs foreign bodies 

 (bones) in the intestines, and obstructions by agglutinated 

 hair at the anus of long haired dogs, are particularly trouble- 

 some. The patients groan, cry or howl during attempts at 

 defecation ; they avoid the act as much as possible and thus 

 bring on constipation. 



b. Frequency of defecation. Carnivora defecate once 

 or twice daily, herbivora much more frequently ; horses 8-10 

 times, cattle 12-18 times. These figures are increased by 

 bodily exercise — particularly in horses that travel much. 



When the normal frequency of defecation is reduced, we 

 say the animal is constipated. This is mostly the result of 

 diminished peristaltic motion which is also attended with in- 

 creased absorption of fluids. Constipation may result from 

 impaction, occlusion, and dislocation of the intestine, first 

 stages of intestinal catarrhs, inflammations, etc. Constipation 

 is the principal symptom of colic, it may occur, however, 

 without any other colic symptoms. In ruminants the ingesta 

 are usually retained or retarded in the paunch and omasum, 

 rarely in the intestines. 



The term diarrhea is applied to frequent and usually 

 copious evacuations of liquid or semi-liquid feces ; it occurs 

 in all irritated conditions of the intestinal mucous membrane 



