160 STORRS AGRICULTURAL EXPERIMENT STATION. 
The ration consisted of two parts, a basal ration and an addi- 
tional grain ration. The basal ration was made up of coarse 
fodders and grain feeds in various proportions, the whole in- 
tended to furnish two pounds of digestible protein. The addi- 
tional grain feed was made up of different concentrated feeding 
stuffs mixed together in various proportions depending upon 
composition. This for convenience is called a ‘ protein mixture,’ 
and was planned to furnish three-tenths of a pound of digesti- 
ble protein for each pound of mixture. All the cows in the 
test were given the same basal ration, but the amount of protein 
mixture added to it depended upon the amount of butter fat the 
cows had produced.’’ 
‘Tn the winter of 1900-01 four herds were studied a second 
time, after an interval of four weeks from the close of the pre- 
ceding test. In the second test the ration was proposed by the 
Station, and was based upon the yields of butter fat. In the 
preliminary tests, designated as ‘original rations,’ asa common 
thing each farmer fed all the cows a uniform ration, although 
in some cases the amount of grain feeds was varied slightly for 
the different cows A eCOr Te to whether they were fresh or well 
advanced in lactation.’ 
In all, twenty-one herds containing 277 cows were fed a 
narrow ration in comparison with a wider ration fed from two 
to four weeks previously. 
For the sake of comparison the twenty-one original rations 
are grouped in Table 75, and the ‘‘recommended rations’’ fed 
the same herds are grouped in Table 76. 
The average estimated live weight of the cows in the twenty- 
one herds in the original tests was 760 pounds. ‘The second test, 
on the recommended rations, began on the average four weeks 
after the beginning of the first test, and the cows were, therefore, 
four weeks farther advanced in lactation. The herds averaged 
about five months in lactation at the beginning of the first test. 
‘The normal rate of shrinkage in milk flow that would usually 
occur under an efficient average unchanged ration is 2% per 
cent. for every one-half month during the fourth and fifth 
month’’ (Geneva Station Bul. 210). For four weeks (1 month) 
this shrinkage for cows giving 17.25 pounds of milk per day 
would amount to .85 pound. Whether or not this calculated 
shrinkage is applicable to the herds fed the recommended ration 
and under changed conditions will be discussed later. 



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