J 84 EQUINE PHYSIOLOGY. 



by the movement of its circular and longitudinal fibres forces it 

 through the cardiac orifice of the stomach into that viscus. 



The first stage is voluntary, the others involuntary. 



The horse can make from 65 to 90 motions of deglutition per 

 minute for fluids. 



GASTRIC DIGESTION. 



From the difficulty or impossibility of making a gastric fistula 

 in the horse, the amount and composition of the gastric juice is 

 hard to estimate. Its specific gravity is about loio, its reaction 

 acid and its composition is as follows — 



r Water 



Fluids, < Hydrochloric acid \- 982.80 



( Lactic acid ■ 



Solids 17.20 



} 



1000.00 



The solids are — 



Pepsin, 



Milk-curdling ferment, 



Chlorides, 



Phosphates, 



Iron. 



The amount of acids varies from 0.084 P^i" cent, to 0.2 per cent. 

 The juice from the fundus of the stomach contains more fer- 

 ment, more acid and more mucus than that from the pylorus. 



Action of the Gastric Juice. 



The gastric juice changes starch into sugar, not of itself, but by 

 the sahva, which still continues its action, converts vegetable albu- 

 min into peptones, and digests cellulose by fermentation to some 

 extent. In feeding the horse the food should be taken in the follow- 

 ing order :^rs/ water, seco7id hay, third oats, as the water if given 

 last would wash the food into the intestine before it was acted 

 upon by the gastric juice, while if hay was given after oats, it 

 would carry them along with it, as it is principally digested in the 

 intestines, the oats being acted upon by the stomach for the most 

 part. The stomach is never completely empty, as some food re- 

 mains after 24 hours. 



