CHAPTER VI 



THE COMPOUNDS OF ANIMAL NUTRITION, 



CONCLUDED— CARBOHYDRATES, ACIDS, 



FATS, AND OILS 



Much the larger proportion of the dry matter of cattle 

 foods consists of non-nitrogenous material. While these 

 nitrogen-free compounds have not been regarded as 

 fundamentally so important as are the proteins, in quan- 

 tity they unquestionably occupy the first rank. The 

 activities of plant life are largely devoted to their pro- 

 duction, 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 main- 

 taining muscular activity, to be sure, but these compounds 

 are the principal storehouse of that sun-derived energy 

 which furnishes the motive power exhibited in all animal 

 life. They also fill a necessary office in the formation of 

 milk and in the fattening of animals. This class of com- 

 pounds greatly predominates in the usual farm crops, 

 even in those of the legume family. 



87. Elementary composition of the non-nitrogenous 

 compoiuids. — ^The non-nitrogenous compounds contain 

 only three elements — carbon, hydrogen, and oxygen. 

 They may be derived, therefore, wholly from air and 

 water, and they constitute that portion of foods which is 

 drawn from never-failing and costless sources of supply. 

 The elementary composition of typical nitrogen-free 

 bodies is given in this connection: 



(68) 



