Tables of Composition and Feeding Standards. 101 



pared with the carbohydrates. * The product obtained is added 

 to the total quantity of digestible carbohydrates in the given fod- 

 der and the sum is divided by the digestible protein. 



The method of calculating the nutritive ratio for com stover, 

 the digestible nutrients in which are protein 1.7, carbohydrates 

 32.4, and ether extract 0.7, is as follows: 



Ether Heat 



extract. equivalent. 



.7 X 2.4 = 1.68 



Carbohy- 

 drates. 

 1.68 -f 32.4 = 34.08 

 Protein.' 

 34.08 -r- 1.7 = 20 + 



Nutritive ratio 1 : 20. 



In expressing the nutritive ratio of com stover thus, 1 : 20, it 

 is meant that for each pound of digestible protein in com stover 

 there are 20 pounds of digestible carbohydrates and ether-extract 

 equivalent. The nutritive ratios of the several feeds are placed 

 in the last column of the table. The nutritive ratio of oat straw 

 is shown by the table to be 1 : 33.7. This is called a " wide " ratio 

 because of the very large quantity of carbohydrates contained 

 in this feed in proportion to the protein. With Indian corn the 

 nutritive ratio is 1 : 9.8. Such an expression is spoken of as a 

 ''medium" ratio. In oil meal the nutritive ratio is 1 : 1.7, the 

 protein almost equaling the carbohydiates and fat combined. 

 Such an expression is called a ' ' narrow ' ' nutritive ratio. 



133. Wolff-Lehmann feeding standards. — Step by step we have 

 advanced until it is shown in the last table what portion of feed- 

 ing stuffs is available for the nutrition of farm animals. Let us 

 next direct attention to the quantity of the several nutrients 

 in feeding stuffs required by farm animals. While analytical work 

 and digestion trials were in progress by the physiologist and 

 chemist, feeding trials were being conducted to determine how 

 much protein, carbohydrates and ether extract were required to 

 properly nurture farm animals of the several classes, under various 



» American writers generally use the factor 2.2 or 2.25. See Article 61 



