Requisite Constituents of Food. 2 t 5 



young animals and for the formation of eggs, as well as 

 those required to repair the waste arising from the move- 

 ments of the living body, a second variety of food is required 

 (in addition to warmth-giving foods), for the starch and other 

 substances before enumerated cannot supply these wants. 

 Substances possessing this power are termed flesh-forming 

 food. The most important are the gluten, and similar sub- 

 stances, existing in variable quantities in different grains ; 

 in large proportions in the varieties of pulse, as beans, peas, 

 &c. ; and in the materials which form the solid parts of the 

 flesh of animals, of eggs, of milk, &c. In consequence of 

 these substances containing the element nitrogen, which is 

 wanting in the other varieties of food, they are frequently 

 termed nitrogenous foods ; whilst the fat-forming and 

 warmth-giving are called carbonaceous foods. The mineral 

 and the saline substances contained in the bones, and in other 

 parts of the bodies of animals, occur in larger proportion in 

 the bran than in the inner part of the grain. A due supply 

 of bone-making and saline materials is absolutely requisite 

 to the growth of a healthy animal ; as if wanting in the 

 food, the bones become soft and the general health speedily 

 fails." It will thus be seen that what is required in a well- 

 balanced food, are qualities for warmth-giving, flesh-forming, 

 fat, or oil, and bone-making ; but, as there are few foods Which 

 are so balanced, and at the same time as foods are required 

 for special purposes, such as chicken-rearing and fattening, 

 only those foods suitable should be used, or a combination 

 of them. 



By examination the qualities of the various foods have 

 been abundantly proved. If we take barley, one of the com- 

 monest grains given to poultry, we find that it contains a 

 very small quantity of fat or oil, has 13 per cent, of ilesh- 

 forming properties, 55£ per cent, of warmth-giving, and 4 

 per cent, of bone- malting substances. It is, therefore, most 



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