University of Arizona 



331 



Ration 3 — 11 lbs. alfalfa hay 

 40 " silage 

 3 " cottonseed cake 



Eleven cows were available for the test. These were divided 

 into three groups : four in each of two groups and three in the other. 

 Since it was impossible to balance the groups evenly the test was 

 divided into three periods of twenty-eight days each, and the rations 

 were alternated so that each ration was fed to each group of cows 

 for the same length of time. In this way it was possible to over- 

 come the effects of difference of breed, period of lactation, and indi- 

 viduality of the cows. One week interval was allowed between 

 each period to allow the cows to become used to the change in 

 rations. 



No attempt was made to draw any conclusions from the data 

 secured during any one period because of so many factors entering 

 in to influence the results, but the combined results of each ration 

 for the three periods were studied. Table No. XVI shows the 

 total number days each ration was fed, total feed consumed, total 

 milk produced, and total fat yield. 



T.4BLE XVI. SUMMARY OF FEEDS FED AND MILK AND FAT PRODUCE.) 



*3 lbs. alfalfa hay per cow per day was added during last period. 



The cows gave 459.7 pounds of milk and 26.79 pounds of fat 

 more when receiving alfalfa hay and cottonseed cake than from 

 alfalfa and silage, and 590.8 pounds of milk and 20.2 pounds of 

 butter fat more than from the alfalfa, silage, and cottonseed meal 

 ration. This would indicate that the cottonseed cake was a better 

 supplement for alfalfa hay than silage, yet Ration 3, which contains 

 three pounds of the cake in combination with silage and alfalfa, 

 failed to produce as much milk as the alfalfa and silage ration. The 

 amount of milk varies almost directly with the amount of alfalfa fed. 



