SELECTING HOLSTEIN-FRIESIAN 



SIRES FOR HIGH YEARLY 



PRODUCTION 



A Detailed Study of the Records of 1478 Registered Animals Proving the 

 Value of Certain Blood Lines in Transmitting High Production 



R. E. Hunt 



Virginia Agricultural Experiment Station, Blackshurg 



SUCCESS in the dairy business de- 

 pends very largely upon average pro- 

 duction of the cows that are in the 

 milking herd. The average of all dairy 

 cows in the United States is very much 

 below what it should be. The function 

 of the improved dairy breeds is to 

 increase this low average to a very 

 much higher average. 



The breeder of purebred dairy stock 

 seeks to raise the best producers possible 

 in order that his milking herd may reach 

 a very high level of production. Males 

 from the purebred herd may be sold to 

 dairymen with grade or purebred 

 milking herds with the result that the 

 production of their heifers from this 

 registered sire will be quite superior to 

 their dams. In order to assure success 

 in breeding the above mentioned stock, 

 it is necessary to have some definite 

 method of making the proper selection 

 of the females, and especially the herd 

 sire. This means that we must have 

 some method of locating the lead- 

 ing blood-lines of the breed and the 

 possibilities of the sire selected proving 

 his prepotency for average high pro- 

 duction. 



Of course, most dairymen and pure- 

 bred breeders will select young untried 

 sires. This means that their sire's 

 future will be judged entirely by the 

 records of his ancestors. The Blue Books 

 of the Holstein-Friesian Association of 

 America give a great mass of very 

 valuable material, but it does not show 

 the lines of greatest production or 

 the way this lineage transmits high pro- 

 duction. This paper is an attempt to 

 show the lineage of highest pro- 

 duction and how it is transmitted down 

 through the various generations. 



METHODS OF ESTIMATING RECORDS 



The data reported in this paper was 

 taken from volumes 24 to 30 inclusive 

 of the official Blue Book and Herd 

 Books of the Holstein-Friesian As- 

 sociation of America. The pedigrees 

 of all cows having yearly records 

 equivalent to or greater than 600 

 pounds of butterfat were tabulated for 

 three generations, and all cows having 

 yearly records equivalent to or greater 

 than 800 pounds of butterfat were 

 tabulated for five generations. 



Yearly records were chosen for the 

 basis of this study because the dairy- 

 man milks his cows twelve months 

 in the year and wants to know what 

 he can expect from the daughters of the 

 herd sire of his selection. 



The records of all cows used were made 

 comparable by estimating the amount 

 of butterfat produced by all cows 

 under five years on the basis of the 

 yearly requirements. For the lack of 

 better and more authentic information, 

 it was assumed that the requirement of 

 250.5 pounds of butterfat for a heifer 

 freshening at the age of two years or 

 less, increased by (.1) one-tenth of a 

 pound of fat for each day over two 

 years until the age of five years is 

 reached, when the cow is considered 

 mature and the required production 

 is 360 pounds of fat. The record of a 

 heifer freshening at the age of two 

 years and no days and producing 500 

 pounds of fat would be considered 

 equivalent to a 718.4 pound mature 

 record. The number of pounds of fat 

 produced times 360, the requirement 

 for a mature cow, divided by the 



369 



