January, 1938] 



Dairy Herd Replacements 



23 



/N OEX ( 1 

 I 90 



120 



reao 



18 90 



1900 



I9IO 



/920 



/930 



/9'^0 



Figure 1. Index numbers of the January 1 farm price of dairy cows and the 

 purchasing power of dairy cows in the United States, 1880-1935* 



(1910-14=100.) 



market or from a shipping point, the greater is his comparative advan- 

 tage in raising heifers. The type and topography of the road from 

 farm to shipping point is also important. A farm located three miles 

 from a railroad and on a hilly dirt road may be at a greater disadvan- 

 tage than a farm on a good highway, but many times as far from a cen- 

 tral market, especially if the former is not situated on a collection route. 



According to Dairy Herd Improvement Association records, full ma- 

 turity in production is not reached until about the sixth year. As shown 

 in Figure 2, heifers freshening at two to three years of age are not ex- 

 pected to produce more than 78 per cent of their ultimate capacity. But 

 during this three or four year period between first freshening and full 

 maturity, the animal is developing in both frame and weight. The feed 

 consumed is performing a dual activity — growing cow and producing 

 milk. 



Roughly the costs associated with the stabling, feeding, and milking 

 of the cows are constant for all ages. But because of lower production 

 at the earlier freshening periods and in aged cows, the cost per unit of 

 milk, not including appreciation or depreciation, is greater in the young 

 and the old cows. In the young cows the increase in value is a factor 

 to be balanced against the higher milk cost. A few men with limited 

 roughage and special milk markets may wish to maintain mostly cows 

 in high production and therefore would ordinarily follow the prac- 

 tice of purchasing five-year old cows and disposing of them whenever 

 their production capacity diminishes. On the other hand, some farm- 

 ers without the advantage of special milk markets would carry their 

 raised heifers to about the third calf freshening period and sell. In 

 such herds, with the exception of the foundation cows, the milkers are 



* Farm Economics, No. 89, page 2162, published by the Department of Ag- 

 ricultural Economics and Farm Management, Cornell University, Ithaca, N. Y. 



