
A STUDY OF RATIONS FED TO MILCH COWS. pau 608 
protein per cow per day was 2.32 pounds and the nutritive 
ratio 1 to 5.9. The average daily milk and butter production 
were 18.7 and 1.05 pounds, respectively. 
With thirteen herds including 156 cows a second test was 
made in which a ration was proposed by the Station, and was 
intended to be richer in protein. In one of these tests the 
ration was not acceptable to the cows, and in another it was so 
nearly like the first ration as to be practically the same. 
Omitting the data for these two herds and comparing the 
results of the first and second tests with the eleven other herds 
it was found that the average amount of protein per cow per 
day was 1.78 pounds in the first test and 2.40 pounds in the 
second test. The nutritive ratio was 1 to 7.7 in the former 
and 1 to 5.1 in the latter. As regards the milk flow and yield 
of butter, there was a slight increase during the second test in 
spite of the fact that the cows were from one to four weeks fur- 
ther advanced in the period of lactation.. The average cost of 
the ration was also reduced about 6 per cent. in the second 
test, in spite of the increased amount of protein fed. If the 
manurial value of the rations is taken into account the ration 
richer in protein was still more economical as compared with 
the lower ration found in actual use. While it would not 
be fair to claim that these differences in the results with: 
the smaller and larger amounts of protein are due wholly to 
the character of the ration, there seems to be evidence that the 
ration had considerable to do with the final results. 
FEEDING ACCORDING TO MILK PRODUCTION. 
In earlier experiments the ration fed during the second test 
was based upon the weight of the cow, the general aim being 
to feed two and one-half pounds digestible protein to 1,000 
pounds live weight where the cow gave an average milk flow. | 
The studies made by this Station, however, as well as those of 
other experiment stations in this country and Europe, indi- 
cated that the quantity of protein in the ration should be based 
rather upon the milk production than upon the weight of the 
cow; so that a small cow giving a large amount of milk should 
perhaps receive more digestible protein than a larger cow with 
a smaller milk flow. With a uniform milk production varia- 
tions of from one to two hundred pounds live weight do not 
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