218 DAIRY FARMING 



only 75 per cent of the December price. Butter is less 

 variable in price. The butter held in storage prevents the 

 winter price from rising as high as it would otherwise go. 

 Under normal conditions this stored butter prevents the 

 winter price from rising high enough to cover the increased 

 cost of feed as it must do in the case of milk. The winter 

 prices of butter and cheese are based not primarily on the 

 cost of winter feed, but on the cost of summer feed plus the 

 cost of storage. 



In spite of this difference in favor of production of butter 

 on pasture, there are some farms that can produce it in win- 

 ter to the best advantage. Occasionally a farmer sells but- 

 ter at retail at such a high winter price that it more than 

 covers the higher feed cost. If the farmer is very short of 

 pasture and has an abundance of cheap winter feed, winter 

 production may pay. Sometimes the pressure of other work 

 in the summer is enough to more than offset the difference in 

 feed cost. Occasionally a farmer has such profitable summer 

 work and so much of it that he cannot afford to milk cows 

 in the summer, but may be able to milk them for butter pro- 

 duction in winter. 



193. Animal Unit Defined. In order to compare the 

 amount of live-stock on different farms, it is necessary to 

 reduce all kinds of animals to some common basis. One 

 cow, bull, or horse is called an animal unit. Two head of 

 young stock are counted as one unit. Seven sheep, fourteen 

 lambs, five hogs, ten pigs, one hundred hens, are each 

 counted as one animal unit. In each case the numbers given 

 represent a group that eats approximately as much food 

 as a cow or horse, and produces manure worth as much as 

 that produced by a cow or horse. Similarly, the number of 

 cattle units on a farm are the approximate equivalent in 



