﻿TRANSMITTING ABILITY OF HOLSTEIN-FRIESIAN SIRES 



25 



Table 13. — Rank of 23 sires according to the average yield of butterfat of their 

 daughters, and rank of same sires according to yield of milk of their daughters 



Sire 



Average butterfat jrield 



Sire 



Average mUk yield 



Daughters 



Dams 



Daughters 



Dams 



G 



Pounds 

 795.9 

 786.6 

 783. 9 

 760.3 

 745.3 

 735.3 

 688.7 

 659.4 

 657.9 

 634.5 

 632.8 

 623.6 

 622.2 

 621.2 

 607.2 

 585. 7 

 556. 3 

 532.2 

 523.5 

 508.0 

 503.8 

 452. 3 

 432.3 



Pounds 

 697.2 

 647.9 

 663.5 

 651.3 

 581. 5 

 658. 7 

 562.4 

 567.0 

 466.9 

 685.8 

 541. 8 

 578.8 

 548.3 

 693. 5 

 589. 7 

 589.6 

 543.1 

 525. 8 

 492.9 

 568.5 

 536. 

 510.5 

 442.7 



E 



Pounds 

 23, 467. 4 

 22, 074. 6 

 21, 755. 4 

 21, 351. 3 

 21, 273. 8 

 20, 137. 4 

 20,* 34. 8 

 19, 872. 9 

 19, 575. 7 

 19,128.4 

 18, 542. 

 18, 305. 6 

 17, 855. 1 

 17, 613. 6 

 17, 418. 4 

 16, 822. 9 

 15, 676. 6 

 15, 584. 6 

 15, 454. 4 

 14, 825. 2 

 14, 175. 6 

 14, 046. 7 

 14, 009. 2 



Pounds 

 20, 044. 4 



C 



C 



18, 670. 2 



E 



F 



18, 854. 1 



F 



D. _ 



17, 580. 9 



B 



B 



17, 138. 5 



J . 



G 



19, 066. 



D 



J 



18, 912. 1 



H . 



H 



A_ 



16, 957. 2 



A 



14, 464. 8 



T 



I__... 



15, 467. 7 



I. 



T- 



18,811.4 



L 



L 



15, 978. 



K 



W. 



18, 880. 6 



W 



Q 



17, 249. 3 



N._. . 



K. 



16, 355. 7 



Q 



N 



14, 907. 5 



_ 



0. 



14, 783. 7 



P 



P 



16, 328. 7 



M 



v.. . - 



17, 564. 2 



V 



M 



14, 015. 8 



S 



R 



13, 991. 4 



u 



U 



14, 666. 



R 



S 



15, 117. 9 









The ranking of these sires in the order of average butterfat yield 

 does not place them, in the same order as when they are ranked 

 according to the average milk yield. Table 13 shows that the better- 

 producing daughters were on the average out of the better-producing 

 dams. 



It will be noted that there is a gradual decline in average milk 

 yield of the dams in somewhat the same order as that of the daugh- 

 ters, though the decline is not uniform. The average production of 

 butterfat of the daughters of the 10 sires at the head of the list is 

 724 pounds, and the average production of their dams is 618 pomids. 

 The average production of the daughters of the 10 sires at the bottom 

 of the list is 532 pounds and the average production of their dams 

 549 pounds. The same comparison holds with the milk yield, show- 

 ing that on the average the sires at the head of the list were mated 

 with better cows than the sires at the bottom of the list, and that 

 the dams as well as the sires are contributing to the inheritance that 

 determines the producing capacity of the daughters. 



The number of cases, however, in which sires raise or lower the 

 production of the great majority of their daughters (see Table 2) 

 regardless of the production of their dams, apparently indicates 

 that if the sire is homozygous for the factors that govern high or 

 low milk yield he is likely to have more influence on the production 

 of a group of daughters than have the dams, because of the proba- 

 bility of some or all the dams being heterozygous in their inheritance 

 governing production capacity. 



Even in the case of the sin; who improves approximately half 

 his daughters and low(!rs the production of the other half, the pro- 

 duction of nc'itrier tin; poorer nor the bettc-r daughters s(M'ms to 

 follow very (;los('ly that of the dums. Take the (;ase of sire N ; 5 of 

 hjs 9 daughters are better than their dams and the otlier 4 are poorer. 

 Here there is something of a negative correlation })ctwcen the 

 daughters and their dams with respect to production; that is, his 



