Vaiu^ of tlie Different Nutrients. 117 



While it is important from a scientific standpoint to study the 

 fuel value of rations, such use in compounding them for practi- 

 cal purposes is hardly warranted, since a statement of the several 

 nutrients themselves is mox-e explicit and satisfactory. 



150. CoficSusions relative to feeding standards. — The vast 

 amount of work of the chemist and physiologist as shown in the 

 several tables under discussion in this chapter must be apparent 

 to every student who has followed the subject to this point. 

 When one learns that these tables after all are not what they first 

 seem as to exactness and reliability, he is tempted to cast them 

 aside as of no value in the conduct of his feeding operations. Due 

 reflection will check such a course, for enormous gain has already 

 come to our stock interests from this source. Tables of chemical 

 composition and feeding standards are efforts toward a desired 

 end, and the student will always study these with interest, and 

 the prudent feeder will never ignore them in his care of live stock. 



V. Placing Money Values on the Different Nutrients in Feeding Stuffs. 



151. Character of the inquiry. — Since commercial fertilizers are 

 sold on their content of nitrogen, phosphoric acid and potash, it 

 seems possible to ascertain the values of the several common feed- 

 ing stuffs from their content of digestible protein, carbohydrates 

 and ether extract. (420) This matter takes concrete form in the 

 questions asked at farmers' meetings and in the agricultural 

 papers as to the relative values of different feeds; for example, 

 the value of a ton of bran or oil meal when corn or oats are worth 

 a certain sum per bushel. 



152. Studies of values. — More than a generation ago Wolff, 

 studying the by-products of flouring mills and oil factories, 

 based calculations on the current prices of these several feeds, and 

 found that, allowing the nitrogen- free extract a value of 1, protein 

 had a relative value of 2.4, and ether extract 3. 



Konig placed the ratio of protein, fat and nitrogen-free extract 

 at 2.7 : 2.9 : 1. The German ISTatural History Society, i after 

 investigating the matter, concluded that the average values of 

 nutrients of the leading feeding stuffs of Grermany were as 3 : 3 : 1 



1 Landw. Jahrb. 9, p. 805. 



