38 



DAIRY FARMING 



grains. Then again the matter of proportioning the 

 quantity of nutrients to the weight of the animal can at 

 best give only approximate results. The actual milk and 

 butterfat production must always remain the principal 

 factor in determining the quantity of nutrients required 

 by the dairy cow. 



Calculating Rations. By a ration is meant the amount 

 of feed required by an animal in twenty-four hours. 

 The method of compounding rations consists in selecting 

 from the feeds at our disposal such quantities as will con- 

 tain the amount of nutrients called for by the standard. 

 To illustrate, let us make up a ration for a cow yielding 

 daily 22 pounds of milk of average quality, using the 

 Wolff-Lehman standard (p. 37). The feeds at our dis- 

 posal are wheat bran, cottonseed meal, corn meal, corn 

 silage, corn stover and clover hay. 



By a number of trial calculations we find that the 

 required nutrients are obtained by selecting 9 Ibs. of 

 wheat bran, 4 Ibs. of corn, i Ib. of cottonseed meal, 5 Ibs. 

 of corn stover, 5 Ibs. of clover hay and 30 Ibs. of corn 

 silage. The calculation is made from Table II (p. 35) in 

 the manner shown below : 



Protein in 9 Ibs. bran 

 Protein in 1 Ib. cotton seed meal 

 Protein in 4 Ibs. corn 

 Protein in 30 Ibs. corn silage 

 Protein in 5 Ibs. corn stover 

 Protein in 5 Ibs. clover hay 



