CHAPTER VI 



THE COMPOUNDS OF AXIMAL XUTRITIOX, COXCLUDED — 

 THE XITROGEX-FREE COMPOUNDS 



Much the larger proportion of dry cattle foods 

 consists of non- nitrogenous material. This is espe- 

 cially true of hays and cereal grains, consequently we 

 find that from 75 to 80 per cent of the dry matter 

 stored in a farmer's haymows and grain-bins is made 

 up of substances of this class. While these com- 

 pounds are not regarded by many as fundamentally so 

 important as the nitrogenous, in quantity the}' un- 

 questionably occupy the first rank. The activities of 

 plant life are largely devoted to their production, and 

 their use by animal life is correspondingly extensive. 

 They may properly be called the main fuel supply of 

 the animal world. Other nutrients aid in maintaining 

 muscular force and animal heat, to be sure, but these 

 compounds are the principal storehouse of that sun- 

 derived energy which furnishes the motive power ex- 

 hibited in all animal life. They are also important 

 building materials, for they fill a necessary office of 

 this kind in the formation of milk and in the growth 

 and fattening of animals. 



The compounds of this class contain only three ele- 

 ments, — carbon, hydrogen and oxygen. They may 



(71) 



