324 MANAGEMENT AND BREEDING OF HORSES 



house for this materia^ and regulates the supply to the 

 blood in such a manner that the muscles receive a uni- 

 form amount. It is also probable that the liver has the 

 power to make carbohydrates from the fats and protein 

 of the food. The quantity of fats in the body varies with 

 the condition of the animal. They are found in all parts 

 of the body and almost pure in the fatty tissues. It is 

 probable that fats can be made from protein and carbo- 

 hydrates as well as obtained from the fats of the food. 



THE FOOD 



Any material that an animal can take into the diges- 

 tive organs and from which matter can be absorbed for 

 the nourishment of the body may be considered as food. 

 The value of food depends, among other things, on its 

 composition and digestibility. There is a tendency to 

 ignore this, and a ton of one food such as oats is often 

 considered as valuable as a ton of another such as corn, 

 whereas the materials actually available to the animal 

 may be much larger in one case than in the other. Thus, 

 in feeding horses the available nutrients of the food 

 should be considered. 



Composition of food. — As in the case of the animal 

 body, the common foods are made up of water and dry 

 matter, while the dry matter consists of ash,' protein, car- 

 bohydrates and fats. Of these the protein, carbohydrates 

 and fats are spoken of as the nutrients, since they fur- 

 nish the body with the necessary matter and energy. 



Water. — All foods, even the driest, contain some water. 

 The amount varies widely in different foods, running as 

 low as 8% in some of the concentrated foods to as high as 

 90% in some of the more succulent foods. Even dry hay 

 varies in this respect, alfalfa containing only 6.5%, while 

 some of the clovers run as high as 20%. Water is not a 

 nutrient, therefore its presence is an important factor in 

 determining the value of a food. 



