52 



DAIRYING 



periods, etc. Some breeders are now trying to combine many of 

 the good qualities of several breeds into one, such as a large 

 quantity of rich milk. 



Such a development as this may be promoted by keeping in- 

 dividual records of both feed and milk per cow per day as the feed 

 consumed per unit of milk or milk fat is of great importance in 

 the collection of data to be used in selecting cows to breed from 

 and from which to build up a herd having the characteristics most 

 desired. 



The breed of a cow, however, does not always insure her pos- 

 sessing the peculiar qualities of that breed, as there are many ex- 

 ceptions and considerable variation in the cows of one breed. This 

 is well illustrated by the following figures collected during the 

 Dairy Cow Demonstration at the World's Fair held at St. Louis. 

 The cows of each breed were all under one management which was 

 trying to make each cow give the most milk possible at the least 

 food cost; but the figures show considerable variation in the ca- 

 pacity of the cows of each breed. 



Variation in Milk Production of Cows of One Breed 

 St. Louis Dairy Test, 120 Days' Record. 



Holstein 



Jersey 



Best i Poorest ! Ave. 



Best ! Poorest I Ave. 



No. cows in he id 



15 



25 



