282 THE FEEDING OF ANIMALS 



hydrates, and fats, and this being done, the relative 

 agricultural values of feeding-stuffs would be estab- 

 lished on the basis of their composition and digestibility, 

 thus providing purchasers with a guide for selecting the 

 materials costing the least in proportion to their value. 



378. Commercial values of feeding-stufifs. — ^Experi- 

 ment stations have for many years published relative 

 commercial valuations of the various brands of fertilizers 

 that are in the market. We are not able to establish values 

 similarly with cattle foods because of existing condi- 

 tions. The dry matter of cattle foods is made up of 

 ash, protein, carbohydrates, and fats. We practically 

 ignore the ash and base the value of a given food upon 

 the other three classes of comppunds, which are the 

 same in number as the three useful ingredients of 

 mixed fertilizers. Now if we could find in the market a 

 cattle food supplying only a single ingredient, as is the 

 case with fertilizers, we could from its composition and 

 market price determine the cost of this ingredient. As a 

 rule, however, these classes of nutrients must be bought 

 in a mixed condition. All commercial cattle foods, except, 

 perhaps, one waste product from sugar production, are 

 mixtures in varying proportions of protein, carbohydrates, 

 and fats. When we buy one we buy all three. Protein, 

 starch, sugar, or oils as foimd in commerce have become, 

 through the necessary processes of separation, too costly 

 to be considered for cattle-feeding purposes, and their 

 prices in these forms are not a proper basis of calculation. 

 If, therefore, a farmer pays $25 for a ton of wheat bran, 

 the problem would be what proportion of this sum he 

 should assign to the 320 poimds of protein, the 1,240 

 pounds of carbohydrates, or the 84 pounds of fats. 



Commercially considered the problem is complex. 



