THE FEED REQUIREMENTS OF FARM ANIMALS 123 



stituted for part of the ration. Inasmuch as it is not de- 

 sirable to lessen the bulk of the ration, one may substitute 

 two pounds of linseed meal for two pounds of the oats of the 

 ration. The ration then contains the following nutrients : 



The nutritive ratio is H-^ + (2.25 X 0.7) ^^ ^ . . ^ 



J- .y 



This ration, except being a trifle low in dry substance, comes 

 very close to satisfying the standard. Of course, in many 

 cases, especially until one has had considerable practice in 

 the calculation of rations, the trial ration may have to be 

 modified several times before the ration conforms with the 

 standard. However, by applying his practical knowledge 

 and the rules in Chapter VII, the student should not have 

 much difficulty in calculating balanced rations. 



Other rations are calculated according to the Wolff- 

 Lehmann standard in the same general manner. It should 

 be borne in mind, however, that as previously mentioned, 

 other factors, such as the proportion of concentrates to 

 roughages, the general practicabihty, and the cost of the 

 ration, as well as its content of digestible nutrients also must 

 be taken into consideration. 



In view of modern investigation, certain modifications 



