38 



PRINCIPLES OF FEEDING FARM ANIMALS 



the saliva and, l:)y means of ducts, empty it into the mouth. 

 The saUvary glands of the cow are shown in Figure 6. 



The Uver, located just back of the stomach, is the largest 

 gland in the body. It produces the bile which it stores in 

 the gall bladder and, when needed, empties it into the upper 

 part of the small intestine. It is of interest to note that 



the Uver of the 

 horse contains no 

 gall bladder, the 

 bile being stored 

 in the ducts them- 

 selves. 



The pancreas, 

 commonly called 

 the sweet-bread, 

 is a small gland 

 which Hes along 

 the upper part of 

 the small intes- 

 tine. It secretes 

 the pancreatic 

 juice into the 

 small intestine. 

 The relationship of the different parts of the digestive 

 system, in case of the horse, is shown in Figure 7. 



Enzymes. — Digestion is accomplished for the most part 

 by means of substances known as enzymes, or ferments, 

 which are formed l)y the salivary glands, by glands in the 

 walls of the stomach, by the pancreas, and ])y glands in 

 the walls of the small intestine. An enzyme may be defined 

 as a substance secreted by cells^ which has power, under 



Fig. 6. — Head of cow, showing some of the 

 salivary glands, a, h, c, d, e, f, g, h. (Sisson, 

 Veterinary Anatomy.) 



