CATTLE 1475 



of the sire and the individuaHty of the animal are the real determining 

 factors with reference to the milking fvmctions of the cow. Inferior milk- 

 prodncing cows are rather the fruit of heredity than of the treatment re- 

 ceived when they were young. 



Age of calving and milk production. — The experimental data given and 

 a compilation of the records of the University of Missouri herd for twent)""- 

 two years show that on an average the maximum production of milk is se- 

 cured from cows well matured before they commenced lactation. The ma- 

 ximum production among ninety-five cows was obtained from those calving 

 between the ages of 28 and 32 months, the minimum from those calving 

 under 20 months old. 



Relation of ration to dairy type. — Heavy feeding of young cows tends 

 to produce larger and rather coarser animals than does light feeding. At 

 the time of calving the conformation of the animal bred on heavy grain 

 ration is somewhat different from that of one bred on a ration of roughage. 

 If both cows are given the same ration after calving, this difference soon 

 disappears. 



Age of calving and dairy type. — Early calving tends to produce a 

 smaller and more refined type of cow than that which results from 

 calving a year later. 



Relation of roughage fed to digestion. — The opinion of breeders is that 

 a cow bred principally on roughage has a greater capacity for the elaboration 

 of the food when it reaches maturit}-. This opinion has not been confirmed 

 by the writer's investigation. For a short time after calving there was a 

 marked difference, but this disappeared graduall}?^ and two months later 

 there was no difference between the two groups. It was proved that the 

 animals of the two groups required the same quantity of nutrients to produce 

 a pound of milk. 



Conclusion. — It is possible to influence, to some extent, the rate of 

 growth, the size when mature and the type of cows, by the liberaHty of the 

 ration during the period of growth, and by the age at first calving. Even 

 within limits of variation much wider than normal, the character of the ra- 

 tion, with reference to the amount of nutriment that it yields, has no appre- 

 ciable effect on the milking functions of the cow when it has reached 

 maturity. 



The age at first calving is a factor of some importance with respect 

 to the development of the ' milking functions of the cow. Calving at 

 a very early age prejudices the best development of the milking function 

 and nothing is gained by retarding it too nuich. 



iog3-The Costof Food in the Production of Milk. — CRowTHERCh, and kuston \.c, in 



the Univer.tilv of Leeds and Yorksliirc Council fo'' A^ricullural 1 liucition IhtllclinKo. 98, 

 pp. i-,57- Leeds., 1015. 



Dxiring the four years from April igii to March 1915, a continuous 

 series of investigations on the cost of feeding cows, and the yield and 

 quality of the milk produced by them has been carried out on a number 

 of farms in the North Riding of Yorkshire. 



The present report deals with the data obtained diiring the twelve 



