108 Feeds and Feeding. 



stover, 10 potrnds; com meal and bran, each 5 pounds; oat straw 

 and oil meal, each 3 pounds. 



137. Concerning rations. — In preparing a ration it is well to start 

 with what may be called a "trial " ration, composed of two or 

 more kinds of coarse forage with a moderate supply of some 

 desirable concentrate. When the nutrients these furnish have 

 been placed in tabular form, a few trials will determine the 

 quantity of other concentrates necessary to bring the ration up 

 to the standard. It is usually impossible to compound rations 

 for ruminants from common American feeding stuffe which will 

 furnish the large amount of dry matter called for by the Wolff- 

 Lehmann standard. While volume is an important fEictor in 

 feeding, it is better to allow the ration to fall below the standard 

 in dry matter than to add so much coarse forage with its large 

 percentage of inert matter. Our common feeding materials are 

 of such composition that in placing enough of them in the ration 

 to furnish the requisite protein and carbohydrates, there is usually 

 an excess of ether extract according to the standard, but this 

 cannot be avoided. There is no direct way of calculating the 

 exact quantities of the nutrients to be used in formulating rations, 

 the desired result being reached only by repeated trials, each 

 bringing the calculation nearer the desired standard. With the 

 explanations given, the stockman should find no difficulty in 

 calculating rations for the farm animals under his care. 



m. Feeding Tables and Standards. 



138. The first feeding table. — The first attempt to systematically 

 compare various feeding stuffs one with another was by Thaer, > 

 who in 1810 published a table giving what he termed "hay 

 equivalents." With common hay as the standard unit, the feed- 

 ing values were in part as follows: 



One hundred pounds meadow hay is equal in feeding value to — 

 200 pounds potatoes. 602 pounds cabbages. 



625 pounds mangels. 91 pounds clover hay. 



417 pounds rutabagas. 91 pounds alfaUa hay. 



Naturally, opinions varied as to the comparative values of vati- 



» Thaer, Landwirtschaft, New Ed., 1880, p. 211. 



