30 



DISEASES OF THE DIGESTIVE APPARATUS 



stain them greenish-black and iron preparations turn them black; on 

 meat and fat mixed they are dark gray-brown, and on bread and milk 

 diet they are yellow-brown or almost clay color. If the animal has eaten 

 much bones, they are whitish. The alimentary matter cannot be dis- 

 tinguished with the naked eye, except in the case of bread, which is passed 

 almost as it is taken into the stomach. Bodies, such as wood, bones, 

 hair, straw, earth, etc., can also be seen in the faeces. Under the mi- 

 croscope (Fig. 14) we can see numerous particles of food that have 

 passed without digesting in animals that have good health. In impaired 

 digestion we see pieces of muscle, connective tissue, etc., with the naked 

 eye. 



The following deviations in the appearance of the faeces may be 

 observed : 



If the faeces contain large quantities of food that is ordinarily very 

 easily digested, or of food that shows little or no evidence of having been 



■iW 



Fig. 14. — Microscopical examination of the fsece?. Vegetable matter, starch cells, muscular fibres, 

 epithelial cells, and fungoid growths. 



digested, disorder of the stomach or intestines is indicated. This con- 

 dition may also result from fevers, gastro-intestinal catarrh, from increased 

 peristalsis, forcing the food through the intestinal canal before it has 

 had time to digest, from fright, the presence of irritants in the food, 

 from the administration of laxatives or in old, exhausted or weakened ani- 

 mals. Biliousness will produce a stool that is yellow colored. Continuous 

 diarrhoea produces a mucous or watery appearance of the faeces. In 

 catarrh of the intestines the faeces contain a large quantity of mucus 

 and have a peculiarly foamy appearance. Clrayish-white, or clayey, 

 with a dull gloss indicates a plugging of the bile duct or some stoppage 

 of the flow of bile (retentions icterus). The presence of pus indicates the 

 bursting of some suppurative foci into the intestinal track, such as ab- 

 scesses or ulceration of the large intestine, or the rectum. Bloody stools 

 are frequently passed after a digital examination of the rectum, insert- 

 ing the thermometer, from certain poisons, so-called hemorrhagic en- 



