THIRTY-SEVENTH ANNUAL CONVENTION. 261 



Comparison of Results of the Two Trials. 



In regard to the yield of butterfat the results of the two 

 trials are almost identical. In the first trial there was an increase 

 of 7.5 per cent in butterfat yield in favor of the narrow ration; 

 during the second period the increase was J.6 per cent. The 

 narrow ration also showed a higher per cent of butterfat in both 

 trials, being 0.24 per cent higher in the first trial and 0.17 per 

 cent in the second. The yield of milk was 0.8 per cent greater 

 with the medium ration during the first trial, but during the sec- 

 ond trial the narrow ration produced the more milk, being 3.4 

 per cent greater than that from the medium ration. The live 

 weight of the cows was practically the same for both narrow 

 and medium ration during both trials. 



Relative Economy of Narrow and Medium Ration. 



So far as concerns the experimental results in this bulletin, 

 a comparison of the ''narrow" and "medium" rations is equiva- 

 lent to a comparison of corn meal and cottonseed meal. It was 

 learned that cottonseed meal (narrow ration) produced more 

 butterfat than the corn meal (medium ration), when fed in the 

 quantity and combination as reported in these trials. To get the 

 full difference in the value of these two feeds, however, it is nec- 

 essary to consider, in addition to their respective values as but- 

 terfat producers, also their market and fertilizing values. 



It was stated at the outset that the ration fed during Period 

 II was the same as that fed during Periods I and III, except that 

 2.5 pounds of cottonseed meal were replaced by an equal weight 

 of corn meal. The cost of the former feed was 1.3 cents per 

 pound, while that of the latter was 1.5 cents, making a saving 

 of 0.2 cent per pound in favor of the cottonseed meal. 



Comparing the two feeds solely on the basis of their fertil- 

 izing value it is found that cottonseed meal is worth 1.4 cents per 

 pound and corn meal 0.38 cent per pound, a difference of 1.02 

 cents per pound in favor of the cottonseed meal. Adding to this 

 the difference in the original cost of the two feeds, we find that 

 each pound of cottonseed meal replaced by an equal weight of 



