RELATION" OF PRODUCTION TO INCOME FROM COWS. 3 



452 active associations in the United States. The map (fig. 2) shows 

 the location of these associations. 



HOW THE RECORDS WERE STUDIED. 



The individual cow record includes the name, breed, age, and 

 weight of the cow. It also includes date of freshening, names of 

 dam and sire, months in milk, pounds of milk produced, butterfat 

 test, pounds of butterfat, price of product, total value of product, 

 feed consumed, days on pasture, cost of pasture, cost of roughage, 

 cost of grain, income over cost of feed, returns for $1 expended for 

 feed, feed cost per pound of butterfat, and feed cost per 100 pounds 

 of milk. 



In making the herd and association summaries here discussed the 

 records of all cows on test 4 months or more were included. That is 



Fig. 



; the i- 



-liriu- associations in the United Stat! 



July I. 1921. 



the way such summaries are made by the testers in nearly all the 

 cow-testing association.-- in the United States. In all other tabula- 

 tions only the records of cows that were on test 12 consecutive 

 months and had breed and aire given were used. The reason for dis- 

 carding the shorter records in making tabulations was to avoid pos- 

 sible error due to the use of SUch records. The possible error due to 



a ii- -i records, however, is probably negligible, as average 



yield, cost, and income proved to be about the same per cow-year' 



v, hen the records of all COWS On test Were included as when only the 



ords of those on te-i L2 months were included, (^cr Table L) 

 This indicates thai the herd and ae ociation summaries as now ob 



■ to 1 able 1. 



