51 



moderate ration. Some allowance must, of course, be made 

 for the advance in the lactation period, but even when this is 

 done, there is little that can be said in favour of the change 

 in the ration as far as lot I. is concerned. 



While there has thus been an increase in the yield of lot I. 

 during- the second and third weeks, it will be observed that 

 there was an increase during the second week also in lot II., 

 although there was a marked falling off in the first week as 

 compared with the end of Experiment C. It seems fairly 

 clear that while increasing or decreasing the quantity of con- 

 centrated food may cause temporary differences in the milk 

 yield, there does not appear to be any regular and consistent 

 connection between the two things, as long: as a moderate 

 ration is supplied to the cows. 



One other observation may be made in this connection. 

 The results seem to indicate that a heavier ration may be used 

 with profit early in the lactation period than can be employed 

 as the period advances. To increase the ration with the 

 object of improving the milk yield does not, as far as we can 

 judge from these experiments, have the desired effect, pro- 

 vided always that the cows receive in the first place an 

 adequate ration to maintain their condition. It seems also 

 that to reduce the ration of concentrated food even to the 

 extent of 4 or 5 Ib. per cow per day, does not cause the diminu- 

 tion in the yield that one might expect, provided again that 

 the cows are left at the end with a moderate allowance. These 

 experiments show that an allowance of 12 Ib, of concentrated 

 food or more per cow per day may not generally be em- 

 ployed with profit. Moreover, in view of the observations 

 already made on the effect upon the milk of altering the 

 ration, it may be suggested that the allowance of concentrated 

 food given to dairy cows should to a great extent be regulated 

 according to the amount of milk the cows yield, the actual 

 quantity fixed upon at the commencement of the lactation 

 period to be dependent, of course, upon the size and weight of 

 the cows. 



