THE COST OF FEED 13 



In this connection, however, it must be kept in mind that the 

 calculations are based upon the cows keeping a constant weight. 

 If the practice is to underfeed the cows during the winter, 

 depending upon the stored-up energy accumulated by the cows 

 while on pasture, less feed might be given with a return in 

 milk greater than the feed given would supply. This practice 

 is followed by many dairymen, and an allowance must be 

 made when this is done. That is primarily summer dairying; 

 the data which follow are based upon a year-round production. 



The writer has applied the following method to a number of 

 actual cost calculations of feed required and the results are 

 remarkably near the actual — as near no doubt as the actual 

 weight records could be kept in a practical way. 



The difficulty in applying this method to actual records 

 that have been published, except in a very few instances, is 

 that the amount of food secured from pasture has not been 

 stated. A definite price charged for pasture and the actual 

 amounts of the feed are given, but unless it is known what 

 amount of the total feed was furnished by the pasture, the 

 results can not be checked. It is important that cost records 

 give the returns from pasture, or the time the cows were 

 supplied by the pasture. Under some circumstances and con- 

 ditions the pasture would furnish an even greater part of the 

 feed for the year than is suggested by WoU in the work 

 referred to above. 



Before applying the formula for feed cost it will be necessary 

 to give the material upon which it is based. This may be 

 presented in three tables, as follows: 



Table I. Maintenance Requirement tor Cows.' 



Pounds Therms 

 digestible net 



protein. energy. 



Soo-pound cow requires for maintenance 3 3.80 



7SO-pound cow requires for maintenance 4 4.9s 



i,ooorpound cow requires for maintenance s 6.00 



1,250-pound cow requires for maintenance 6 7.00 



I, soo-pound cow requires for maintenance 65 7.90 



' Farmers' Bull. No. 346, U. S. Dept. of Agr., p. 16. 



