394: Report op the First Assistant of the 



change in the quantity or quality of the milk, besides the gradual 

 change as the period of lactation advanced, might be reasonably 

 attributed to the influence of the difl'erent foods. Individual records 

 for each cow were kept, separate analysis of the milk being made. 

 Only the average results are here given. As varying amounts of 

 milk of differing quality were given by differeut animals the actual 

 weights of the several constituents yielded by each cow were con- 

 sidered in determining the average composition of all the milk. 



For the purpose of securing data, other than those here reported, 

 relative to the production of individual cows, it was necessary to 

 feed a fairly constant proportion of grain at certain months of lacta- 

 tion. On this account no results are here reported that have been 

 obtained when coarse fodder only was fed without grain. The 

 grain was fed in moderate quantities, but always separately from 

 the coarse fodder, so that if any should be left at any time it could 

 be weighed. Feeding and milking were arranged as mentioned on 

 page 391. The hay and coarse fodders were fed in quantities likely 

 to be entirely eaten, but account was kept of any food left. Only 

 the weight of food actually consumed is given in the tables. In 

 estimating the amounts of digestible constituents in the different 

 foods, the average co-efficients of digestibility obtained in digestive 

 experiments in this country and Germany were used. Whenever 

 enough data were available the American co-efficients were used. 



In calculating the cost of the rations, whpat bran was rated at $18 

 per ton, corn meal at $20, ground oats at $25, linseed meal, O. P., at 

 $27, gluten meal at $25, wheat middlings at $20, cottonseed meal at 

 $30, gluten feed at $18, and ground flaxseed at $60 per ton. All 

 hay was rated at $10 per ton, corn stover at $6, com silage at $3, 

 clover silage at $3, roots at $3, and all green fodder at $2 per ton. 

 These prices are some of them much higher than those at this time 

 prevailing, but it is thought better to assume the one valuation for 

 an}^ food throughout all the trials extended over portions of four 

 seasons than to attempt to follow fluctuations of market price. 

 Enough data are given to allow of recalculation, by any who may 

 desire, of the cost of rations at other prices for foods than those 

 stated. 



Table I gives the results obtained in feeding seven cows from 

 November 1st to January 31st. These cows, all young, had been 

 in milk on the average 3.9 months at the beginning of this trial, 

 and were then of the average age of 2.4 years. 



