420 PHYSIOLOGY OF THE DOMESTIC ANIMALS. 



carnivora the chyme is scanty, gradually giving up matters ready for 

 absorption, and passes slowly through the intestine. Thus, seven to 

 eight hours after a meal of one thousand grammes of meat, only fifty to 

 one hundred grammes represent the weight of intestinal contents. The 

 small intestine in carnivora is never distended, as in the case of the 

 omnivora, and especially the herbivora, but it is always a flattened 

 cylinder. The stomach appears to regulate the amount which passes 

 into the small intestine. The small intestine in non-ruminant herbivora, 

 as the horse, receives large volumes of chyme from the stomach, and 

 rapidly disperses it through the entire small intestine ; but although 

 the small intestine has a capacity four times as great as the stomach, 

 it never contains as much as may be contained in the stomach when 

 distended, for after a meal the contents of the stomach are rapidly 

 distributed between the small intestine, stomach, and caecum. If the 

 contents of the small intestine of the horse be examined at various 

 intervals after feeding, it will be found that 40 to 50 per cent, of the 

 carbohydrates in the food have been digested in the stomach, while 

 30 to 50 per cent, of the albuminoids and 40 to 60 per cent, of the 

 non-nitrogenous constituents may still be recognized. 



In the horse, the fluid found in the duodenum and jejunum is usually 

 acid in reaction, yellowish in color, turbid, and viscid. It is capable of 

 digesting proteids and starch, and its ferments may be precipitated by 

 alcohol and redissolved in water without losing their activit}^. In the 

 ileum the contents are usually alkaline in reaction, brownish-yellow in 

 color from the bile-pigments, turbid, but contain less mucin than the 

 duodenal contents. Intestinal digestion in the horse is of considerable 

 importance ; only from 23 to 52 per cent, of undigested albumen and 

 from 38 to 59 per cent, of undigested carbohydrates are to be found in 

 the duodenum, although there can be no doubt but that large amounts 

 of entirely undigested food pass from the stomach into the small intes- 

 tine. When the food has a prolonged sojourn in the stomach but 2 to 

 10 per cent, of its proteid constituents ma}^ be left untouched for diges- 

 tion by the intestinal secretions, but where this is not the case it may be 

 safely stated that at least 60 per cent, of the proteids have to be digested 

 in the small intestine. These facts would -seem to. indicate that in soli- 

 pedes digestion is almost continuous. In ruminant herbivora the state 

 of affairs is different ; there, the contents of the intestine only represent 

 one-eighth to one-tenth the amount contained in the stomach, and when 

 rumination is suspended but a comparatively small part of the food 

 remains unchanged to be acted on by the intestinal secretions. In car- 

 nivora, still another state of affairs occurs. The stomach holds almost 

 all the alimentary matter, only small quantities of liquefied chyme pass- 

 ing into the intestine, and as the gastric digestion in these animals is 



