18 Feeds and Feeding. 



30. Pancreatic juice. This colorless, alkaline fluid, secreted by 

 the pancreas or i i sweet breads, ' ' is poured into the intestine at the 

 same time and at about the same point as the bile, so that these 

 fluids act together. The pancreatic secretion contains more solids 

 than the others mentioned, and has therefore a high specific 

 gravity. It is closely allied to blood serum in composition, and 

 contains four ferments, one of which splits fats into glycerin and 

 fatty acids 5 another converts starch into sugar; a third resolves 

 protein compounds into soluble peptones, while a fourth curdles 

 milk. In one way the pancreatic juice resembles saliva, in that 

 it converts starch into sugar. One part of the active ferment of 

 the pancreatic fluid will convert 40,000 times its own weight of 

 starch into sugar and dextrin. Like bile, it converts fat into 

 fatty acids and glycerin; like pepsin, it converts protein sub- 

 stances into peptones. Unlike the gastric juice, the pancreatic 

 secretion acts upon protein in an alkaline solution. Colin and 

 others place the maximum secretion of pancreatic juice in the 

 horse at three-fifths of a pound per hour. 



31. Large intestine. The processes of digestion are continued 

 in the large intestine (colon) of the Herbivora. The stomach of 

 the horse being small, that organ together with the small intes- 

 tine has not sufficient capacity to accommodate the bulky, com- 

 paratively indigestible food usually supplied this animal, and is 

 supplemented by the large intestine, which has a capacity of five 

 or six times the stomach, permitting the retention of a large 

 quantity of food. The large intestine of the ox, which is smaller 

 in proportion than that of the horse, serves the same purpose. 



The main office of the large intestine is to serve as a storage 

 place for the mixed food materials and digestive juices coming 

 from the small intestines, allowing continued action by the latter. 

 Here a partial digestion of cellulose takes place through fermen- 

 tations, all of the juices secreted by the various digestive organs 

 being without effect on this component. The digestion of cellu- 

 lose is as yet not clearly understood, but it seems that under cer- 

 tain conditions gaseous products, mainly marsh gas, are formed 

 in its fermentations. The value of cellulose has for this reason 

 been questioned; but the best authorities hold that the digestive 



