384 



first year's record was taken as a standard with which to com- 

 pare succeeding records and it was found that nine out of the 

 ten cows increased in production after the first year. Somewhat 

 similar results in showing the residual and developmental ef- 

 fects of improved feeding were secured at the Cornell station 3 

 when a herd of sixteen grade and purebred dairy cows which had 

 never before received grain was divided into two lots of eight 

 each. One lot received grain and the other none during the pas- 

 turing season. During this season the grain fed lot produced 

 27% more milk than did the other lot. In the following season 

 six cows of each lot remained and during the pasture season the 

 lot that had received grain during the previous summer pro- 

 duced 16% more milk than did the check lot, both being treated 

 alike the second summer. The increase in production was attri- 

 buted to the grain fed the previous season and was especially 

 noticeable in the younger animals. 



Data showing the influence of the sire on the production of a 

 purebred herd have been obtained at the Missouri station, 4 where 

 during a period of eighteen years, with the system of feeding and 

 management remaining fairly constant, the records of the daugh- 

 ters of six Jersey bulls were compared with the records of their 

 dams. It was found that the average production of the four 

 daughters of the poorest sire for twenty-six lactation periods was 

 19% less milk and 8% less fat than the average production of 

 their dams for twenty-three lactation periods while the average 

 production of the three daughters of the best bull for fifteen 

 lactation periods was 68% more milk and 61% more fat than the 

 average production of their dams for fourteen lactation periods. 

 This valuable and interesting information clearly demonstrates 

 the variation in the ability of different bulls to transmit dairy 

 qualities, and emphasizes the fact that the selection of a bull to 

 head a purebred herd of dairy cattle is a very important matter. 



It is much more difficult, however, to secure data showing the 

 influence of the purebred dairy sire in increasing the production 

 of a scrub or grade herd. In practically all cases where pure- 

 bred sires are used, improved methods of feeding and man- 

 aging the herd are initiated at about the. same time. And while 

 no one denies the value of this introduction of " dairy .blood," 

 definite data showing the value of the purebred sire on the 

 scrub or common herd, independent of improved feeding, have 

 not been available. 



Owing to the large investment required, only a small percent 

 of the dairy farmers can have purebred herds. Consequently the 

 greater part of the dairy products of the country come from 

 grade cows. Therefore everything that will increase their pro- 



3 Roberts, I. P. Sundry Investigations of the Tear. Bull. Cornell Ag. Exp. Sta. 

 49. 1892. 



* Eckles, C. H. Dairy Cattle and Milk Production. July, 1911. 



