360 



IMPROVEMENT AND FEEDING 



starch and sugar ; and fat, in lard. Stock feeds differ in 

 no way from the vegetable food we serve on the table 

 except in their coarseness, and in the fact that heat is 

 seldom applied in preparing them for eating, and in the 

 further fact that no attention is given to seasoning. 



Protein, we have said, contains the important element 

 of nitrogen. Its presence in any feed can be detected by 



AN ELABORATE DAIRY BARN. 



the yellow color produced if a few drops of nitric acid be 

 dropped on it. As found in the white of an egg, it coagu- 

 lates when heated. Its main work is to build tissues, and 

 to repair those that are wearing out. llecent experiments 

 show that it can also take the place, for a time at least, of 

 carbohydrates and fats, but only at high cost. 



Fats and carbohydrates are considered together because 

 their functions in feeding are similar. Both produce 

 energy and yield heat, although fat is two and one fourth 

 times as valuable for this purpose as carbohydrate. Car- 

 bohydrate, however, is of particular importance because of 

 its bulkiness and its high per cent of crude fiber. These 



