320 



THE KOTHAMSTED EXPERIMENTS. 



tion. 



Excess of either the nitrogenous or the non- nitrogenous constituents 

 avdUs >PV su PP ne d over the requirement for sustenance and milk-pro- 

 duction, the question arises — "Whether, or to what extent, it 

 conduced to increase in live - weight of the animals, or 

 whether it was in part or wholly voided and so wasted? 



It would obviously be of interest to trace the connection 

 between variation in the quantity and composition of the 

 food, and the quantity and composition of the milk yielded. 

 But when the influence on the result, of breed, of varying 

 character of individual animals, of period of lactation, and of 

 other circumstances, are borne in mind, it wil] be seen that 

 to treat the subject at all adequately would involve a great 

 deal of detailed illustration and consideration, and occupy 

 very much more space than could appropriately be devoted 

 to it in this place. We must, indeed, limit further reference 

 to the subject of milk-production to one more illustration, 

 showing the influence of period of the year, with its char- 

 acteristic changes of food, on the quantity and composition of 

 the milk. 



The first column of the second division of Table 75 shows 

 the average yield of milk per head per day of the Eotham- 



TABLE 75. — Percentage Composition of Milk each month of 



THE YEAR ; ALSO AVERAGE YIELD OF MlLK, AND OF CONSTI- 

 TUENTS, PER HEAD PER DAY, EACH MONTH, ACCORDING TO 

 ROTHAMSTED DAIRY RECORDS. 



1 Average over 5 years only, as the records did not commence until February 1884. 



