cattle, expected progeny difference, brith weight, weaning weight
Performance records from 1982 to 1992 on 1365 calves for birth weight (BW) and 1492 calves for weaning weight (WW) were analyzed to estimate relationships of purebred sire expected progeny difference (EPD) values for BW and WW to actual crossbred progeny performance. Sires of the calves were Polled Hereford, Simmental, Angus, Salers, Tarentaise, or Charolais. The pooled-across-breed regressions (Ib/lb + SE) of BW and WW of calves on sire EPD were 1 .I 7 ±.31 and .75 + .28, respectively. Residual correlations of BW with BW EPD and WW with WW EPD were .I6 (P< -01) and .05 (P= .10), respectively. Additional regression and residual correlation analyses were conducted in which records from progeny of low-accuracy sires (Acc. < .50) were deleted. The reduced data set included 967 records for BW and 962 records for WW. The pooled-across-breed regressions (Ib/lb + SE) of BW and WW of calves on higher-accuracy sire EPD were 1.28 + .35 and .71 ± .31, respectively. Residual correlations using higher-accuracy sire data of BW with BW EPD and WW with WW EPD were .I8 (P<.01) and .09 (P = .02). Breeders who use BW and WW EPDs as a selection tool should expect such selection to be effective, on average, and reasonably consistent with theoretical expectation. However, some sires and small progeny groups may not rank as expected based on sire EPDs.
Number of Pages
South Dakota State University
Copyright © 1994 South Dakota State University.
Long, M. B. and Marshall, D. M., "Relationship of Beef Sire Birth Weight and Weaning Weight Expected Progeny Differences to Actual Performance of Crossbred Offspring" (1994). South Dakota Beef Report, 1994. 11.