258 DISEASES OF THE PERITONEUM 



Cysts of the ovaries (common in cats). (/) Occurs in the 

 secondary stage of acute circumscribed or diffuse peritonitis. 



2. General Causes.— Ascites often occurs as a symptom of 

 general dropsy, the result of mechanical effects, as in heart 

 diseases, chronic indurative or interstitial pneumonia. In 

 some heart diseases the effusion is confined to the abdominal 

 cavity, in which case it is no doubt due to secondary changes 

 in the liver. Ascites also occurs in chronic diseases of the 

 liver. In young dogs (puppies) ascites is frequently observed, 

 and often disappears as the animal develops, apparently 

 without any particular cause being found. 



Pathology.— The presence of fluid in the abdominal cavity, 

 of varying quantity from a few cubic centimeters to 15-20 

 liters. This fluid has a specific gravity of 1012-1015, a light 

 or yellowish color, clear, and contains, as a rule, but a slight 

 amount of fibrin, or flocculent precipitate. The chemical 

 reaction of the fluid is alkaline or neutral ; the albumin con- 

 tent is about 2 to 5 per cent. Sometimes the fluid will be of a 

 reddish color, due to slight hemorrhages, or to some of the 

 red cells passing out with the serum. This is especially 

 noticeable in obstruction to the portal vein. A greenish 

 cast is noticed when the liver is secondarily affected. The 

 precipitate when examined will be found to contain a small 

 number of leukocytes, fatty endothelial cells, flakes of fibrin, 

 and sometimes red cells, and in rare cases numbers of small 

 cysts of parasites. In dogs and cats the fluid often contains 

 numerous fat cells and has a milky appearance. 



The peritoneum is usually pale, glistening, thickened, 

 especially in cases of long standing or those due to chronic 

 peritonitis. The organs in the cavity are usually anemic, 

 dull on the surface and sometimes atrophic. 



Symptoms.— An enlargement of the abdomen is usually 

 the first indication of the disorder. Until the accumulation 

 of fluid becomes great enough to cause a distention of the 

 abdomen, the symptoms will not be positive enough to make 

 a diagnosis. As the amount of fluid in the abdomen varies 

 greatly, the symptoms will vary considerably in individual 

 cases. The fluid distends the abdominal wall, causing the 

 muscles and skin to become tense, and the abdomen to assume 



