THE FEEDING OF THK ANIMAL 246 



making up a ration ov deciding npon a fodder; 

 since no matter wliat is fed, it is aitnost certain 

 that tlie animal will find in it an aljundant sup- 

 ply of the jiroper mineral elements, with the 

 exi'eption «)!" common salt. 



.'](/. Alhiiniinniil.'i 



442. Th<' protein, or proteids, constitutes a 

 v.TV important group of fodder constituents. 

 Wliile they are of a complex and varied com- 

 position, all contain nitrogen as a distinctive 

 j'oiistituent, as well as carbon, oxygen and 

 hydrogen, and usually sulfur ami })lio>plini-us. 

 It is the nitrogen that gives to the nicnihers 

 of this gi-oup tlu'ir importance as food {."{TO). 



44">. Organic activities can not lj(» maintained 

 without nitrogen. It is an essential constituent 

 of the living animal <»r vegetalde cell, and no 

 new growth can take place without it ; <'on.se- 

 • luenlly it nmst bo constantly supplied in the 

 food of both ]»lant and animal, ii'itrogen is not 

 a ctmstituent of the other groui)S of food el«>- 

 ments, and, therefore, the growth of the animal 

 dt'pen«ls in largo measure on tlio supply of protein. 



411. While more or less protein is foinid in 

 nearly all fodders, its proportion i.s very va- 

 rial>le, and in very many ca.ses is le.^s than is 

 required by the animal to sustain life or to make 

 useful growth. Those fodders that contain large 



