THE FEEDING OF THE ANIMAL 245 



making up a ration or deciding upon a fodder; 

 since no matter what is fed, it is almost certain 

 that the animal will find in it an abundant sup- 

 ply of the proper mineral elements, with the 

 exception of common salt. 



'M. Albuminoids 



442. The protein, or proteids, constitutes a 

 very important group of fodder constituents. 

 While they are of a complex and varied com- 

 position, all contain nitrogen as a distinctive 

 constituent, as well as carbon, oxygen and 

 hydrogen, and usually sulfur and phosphorus. 

 It is the nitrogen that gives to the members 

 of this group their importance as food (370). 



443. Organic activities can not be maintained 

 without nitrogen. It is an essential constituent 

 of the living animal or vegetable cell, and no 

 new growth can take place without it ; conse- 

 quently it must be constantly supplied in the 

 food of both plant and animal. Nitrogen is not 

 a constituent of the other groups of food ele- 

 ments, and, therefore, the growth of the animal 

 depends in large measure on the supply of protein. 



444. While more or less protein is found in 

 nearly all fodders, its proportion is very va- 

 riable, and in very many cases is less than is 

 required by the animal to sustain life or to make 

 useful growth. Those fodders that contain large 



