206 Report oF THE First ASSISTANT OF THE 
per cent. of fat was 5.85, and the lowest, 3.28 per cent. For the 
second period the extremes in daily average milk yield were 32.0 
pounds and 12.0 pounds, and the extremes in average percentage 
of fat were 6.18 and 2.98. For the third period the extremes 
were 31.3 pounds and 12.9 pounds, and 5.02 per cent. and 2.47 
per cent. 
In changing from the ration of the first period to that of the 
second, the nutritive ratio was changed from 1:7.1 to 1:6.0 
although a larger amount of a less nitrogenous grain was fed in 
the second ration. The cost of the ration was somewhat greater 
in the second period, owing to the rather costly grain mixture 
used. The total dry matter and organic matter in the ration 
remained about the same, although there was an increase in total 
digestible nutrients. There was an increase of the protein and of 
the fat in the second ration, and the fuel value was higher. The 
yield of milk increased somewhat, but the amount of the different 
constituents remained the same, although there was a slight 
decrease in the per cent. of fat. The cost of milk was about the 
same as for the first period and the cost of fat somewhat higher. 
In the third periédd, oat-and-pea forage was substituted for the 
alfalfa of the second, making the nutritive ratio much wider, 
although the same kind of grain was fed and the same kind of 
hay. In the ration for the third period there was considerable 
increase of the total dry matter, the digestible nutrients, and of 
the fuel value, the cost also being increased. There was consid- 
erably more digestible fat and about the same amount of protein. 
There was about the normal decrease in milk yield, but accom- 
panied by a slight falling off in total solids, more noticeable in the 
per cent. of fat. The cost of milk and fat production was greater 
in the third period. In the following tabulated form will be 
found the composition of the different foods used in this trial. 
ee ee 
Pei 
Ne ra Soe get 2 Wi Sey 
a 
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