*, 3?2'Sf*V*l 5 * 



102 



might have been expected. In Experiment J, Bulletin No. 2, 

 after the rations were reversed there was a distinct drop during 

 the first week of the experiment on the average of 16 pints in 

 the yield of the cows which had previously received the grains, 

 while in the case of those cows which had not previously 

 received grains there was an increase on the week's average of 

 5 pints per day when they did the receive the grains. At the 

 beginning of the present experiment the average yield of lot I. 

 during the first week of the experiment increased by half a 

 pint, while that of lot II. decreased by 1 pint. These two 

 results might appear to contradict each other, but the differ- 

 ence is only slight in the latter case, and having regard to the 

 fact that lot II. did not take to the grains should not be looked 

 upon as producing a negative result. Especially is this the 

 case in regard to the fact that the milk yield of lot I. 

 consistently declined from the first week to the sixth, while 

 that of lot II. was fairly well maintained throughout the 

 whole period of eight weeks. It will be noted that during the 

 last two weeks of the experiment both lots showed a consider- 

 able falling oft' in the milk yield, while in the eighth week in 

 the case of lot I. there was an increase in the average flow of 

 milk. In the same period lot II. maintained its yield. It 

 has already been suggested from this and the previous experi- 

 ments that the eighth week may mark the period of time when 

 any particular ration might be economically changed for 

 another. Having regard to the period of lactation and results 

 already obtained, it is safe to assume that brewers' grains do 

 increase the flow of milk and that the effect is maintained for 

 a considerable period, though eight weeks in these particular 

 experiments would serve to indicate the limit. It must be 

 borne in mind that the cows under experiment were pregnant 

 and not, as in so many cases where grains are largely used, 

 in a barren condition. 



Quality of the milk. The butter-fat in the milk of each 

 lot in Experiment L is shown in Table XLIII. 



