37 



The effect of grass on the yield of milk is obvious, 

 especially during the first half of the period, and more par- 

 ticularly in the case of lot I. Here, then, it may be urged, 

 is a case of the food directly affecting the yield. There 

 was certainly an increase in the yield of lot I. during the 

 first half of this second experiment as compared with the 

 end of Experiment A, as will be seen by comparing Tables II. 

 and V. But there was also an increase in the yield of lot II. 

 at first, although it was slight compared with that in lot I. 

 Moreover, the superiority of lot I. over lot II. is not main- 

 tained, and by the end of the period of experiment, the average 

 yield per day is below that of lot II., as it was in Experiment 

 A. The difference between the two lots in this second ex- 

 periment, it is true, is not so great as in the first. The fact 

 remains, however, that lot II. from the very outset, and in 

 spite of the alteration in the amount of concentrated food, 

 has given a higher average yield than lot I. In the pre- 

 liminary trials the two lots were fed alike, but lot II. gave 

 the greater yield. During Experiment A, lot II. received the 

 heavier ration, and again gave more milk than lot I. And 

 finally, in Experiment B, during the summer, when lot II. re- 

 ceived only half the quantity of concentrated food supplied to 

 lot I., the average yield of milk in lot II. was again higher 

 than in lot I. This certainly seems to indicate, as has been 

 repeatedly maintained, that the character of the cows is of 

 greater importance as a determining factor in the yield of 

 milk than the food supplied to the cows. And coming to the 

 question more especially under investigation in the present 

 experiment, there is not, so far, sufficient evidence to prove 

 that heavy, as compared with moderate, feeding is always 

 advantageous in the case of dairy cows, when the results are 

 regarded from the milk-seller's point of view. 



The quality of the milk. Table VII. shows the amount 

 of butter-fat in the milk of each lot. 



