62 HORSE MANAGEMENT IN INDIA 



more corn ought to be given. In hot weather, the animal 

 will, naturally, require less food. 



Mastication and Digestion.— The long hairs about 

 the horse's muzzle serve him as feelers in the selection of 

 the food which his lips convey into his mouth, aided, 

 when the fodder offers some resistance, by the front 

 teeth {nippers, or incisor teeth). The mouthful is then 

 conveyed to the grinders, and is ground by them into a 

 pulp. During this operation it becomes mixed with saliva, 

 which, under the stimulus of the food, flows into the 

 mouth from the different salivary glands. This secretion 

 contains the active principle ptyalin — a species of 

 ferment — the of&ce of which is to convert starch into 

 dextrine (a kind of mucilaginous starch) and subsequently 

 into grape sugar, in which form it is absorbed by the 

 system. " A large proportion of this albuminous principle 

 is present in the saliva of the horse, but only traces of it 

 exist in that of man." (Carpenter.) The amount of saliva 

 secreted during mastication is proportional to the hardness 

 and dryness of the fodder. Lassaigne gives, from experiment, 

 the following results : — 



100 parts of dry hay requires 406 parts of saliva. 



„ barley „ 186 



„ oats „ 113 



grass „ 49 



"Bernard was led to suggest that the submaxillary 

 gland ministers to the sense of taste, whilst the parotid 

 is connected with mastication, and the sublingual with 

 deglutition. The size of the parotid in animals is pro- 

 portionate to the degree in which the mastication of their 

 food is performed. It is large in the horse, which lives 



