New York Agricultural Experiment Station. 421 



After changing from tlie first period to tlie second more food was 

 eaten but there was less dry matter in the ration. The cost of the 

 ration was much increased. There was a smaller amount of digesti- 

 ble matter, although there was more digestible protein and the 

 nutritive ratio was made narrower. The fuel value of the ration 

 was noticeably less. Considerably more than the normal decrease 

 in milk flow followed the change in food and the cost of milk and 

 fat production was greater. 



For the third period the amount of each food was increased and 

 a change in the grain made a narrower nutritive ratio. There was 

 an increase in each food constituent and in the fuel value of the 

 ration. The cost of the ration was made a little greater. There, 

 followed almost no decrease in the milk flow and very slight 

 increase in the cost of milk or fat. 



In changing to the fourth period of feeding the cost of the ration 

 was much reduced, less grain and coarse food were eaten. Although 

 the amount of dry matter in the food was not changed less was 

 digestible. The nutritive ratio was a trifle wider and the fuel value 

 was lower. There was about the normal falling off in milk, but the 

 cost of milk and fat produced was considerablj' less. 



During the first period the greatest daily average milk yield was 

 37.7 pounds, and the smallest 13.2 pounds. The highest average 

 percentage of fat was 6.40 and the lowest 2.60. For the second period 

 the extremes in daily average milk yield were 3.50 pounds and 12.3 

 pounds, and in average percentage of fat 6.48 and 2.75. For the 

 third period the extremes in milk yield were 38.9 pounds and 12.5 

 pounds, and in average percentage of fat 6.18 and 2.51. For the 

 fourth period the extremes in milk yield were" 36.8 pounds and 11.8 

 pounds, and in average percentage of fat 6.85 and 2.68. 



In the following table is shown the composition of each food. 



