37. PRINCIPLES OF FEEDING. 



Substances in Bodies of Animals. The bodies of ani- 

 mals contain flesh, fat, bones, teeth, hair, etc. ; or, we may 

 say that their bodies are composed of water, ash (mineral 

 matter), protein, and fat. These are the substances that 

 must be supplied in the food that the animals eat. The 

 body is more than half water, and it is fortunate that ani- 

 mals have but little difficulty in getting it. Besides the 

 water that they drink, a large part of their food is com- 

 posed of water. The ash, or mineral matter, is found in 

 all of the foods that animals eat. The largest part of it is 

 phosphate of lime. Protein is the name given to the most 

 important group of substances to be supplied by the food. 

 It forms the principal part of the flesh, skin, brain, and 

 nerves. It contains nitrogen as its most important ele- 

 ment. Fat is found in nearly all parts of the body, and is 

 very important in the composition of milk. 



Substances to be Studied. Little attention need be 

 given to supplying water or ash to animals. These may 

 be obtained ordinarily in large quantities without cost. 

 The protein and the fat-forming foods, however, require 

 considerable attention. They are the expensive part of 

 the food of an animal, and should be fed with care so that 

 there may be no loss. 



Protein and Carbohydrates. These are two words 

 that may seem difficult to understand at first, but they are 

 really very simple. Use the words whenever possible, 



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