182 DISEASES OF THE INTESTINES 



CONSTIPATION. OBSTIPATION. INTESTINAL 

 OBSTRUCTION. 



Definition.— An infrequent or difficult evacuation of feces 

 which are abnormally dry or hard ; or may be retained. 



Etiology.— The common causes of constipation in dogs are 

 lack of exercise and feeding dry food. Dogs kept in the 

 house or kennel often withhold the feces until they become 

 hard and dry. Usually in old dogs the peristalsis becomes 

 slowed and there is lack of tone in the muscular wall with 

 some dilatation of the large bowel which causes constipation. 

 The passage through the intestine may be blocked by fecal 

 masses (coproliths) , foreign bodies, calculi, parasites or hair 

 balls, the latter being more common in cats as they lick off 

 and swallow loose hair. The lumen of the intestine may be 

 narrowed as a result of chronic inflammation, cicatricial 

 contraction, stenosis, tumors within the wall, or hemorrhoids. 

 Causative conditions external to the bowel are hernias,, 

 fibrous adhesions or tumors. Other causes are chronic 

 inflammation of the liver with suppression of bile; chronic 

 diseases of the spinal cord; enlarged prostates in old dogs; 

 chronic inflammation of the anal glands ; agglutination of the 

 hair with feces at the anus in long-haired dogs. Rabbits 

 are commonly affected by eating too much dry food. Hair 

 balls or masses of hair and feces are often found in these 

 animals. Birds occasionally swallow feathers which accumu- 

 late in the intestines interfering with the passage of the con- 

 tents. The most common causes are dry feed and foreign 

 bodies. 



Pathology.— The feces are dry, hard, usually of a light gray 

 color and sometimes covered wilh mucus or streaked with 

 blood. Coproliths or calculi or impactions of large size often 

 result in necrosis of the intestinal wall with perforation and 

 peritonitis. 



Symptoms.— Mild cases show only difficult defecation at 

 long intervals (two to four days). The feces are very dry, 

 hard and may be streaked with blood from injuries produced 

 in the rectal mucosa. 



In severe cases the retained feces decompose producing 



