Submitted to: Beef Improvement Federation Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 4/30/2009
Publication Date: 5/3/2009
Citation: Kuehn, L.A., Van Vleck, L.D., Thallman, R.M., Cundiff, L.V. 2009. Across-Breed EPD Tables for the Year 2009 Adjusted to Breed Differences for Birth Year of 2007. Proc., Beef Improvement Federation 41st Research Symposium and Annual Meeting, Sacramento, CA. April 30-May 3, 2009. pp. 160-183. Interpretive Summary:
Technical Abstract: Records of F1 and 3-way cross progeny of 18 breeds of sire and maternal grandsire, respectively, were used to estimate differences among the breeds for birth, weaning, and yearling weight and for maternal effects (16 breeds) of weaning weight and among 11 of the 18 breeds for carcass marbling, ribeye area, and fat depth (10 breeds). The records were also used to estimate regression coefficients of progeny performance on breed association EPD. The regression coefficients represent the proportion of the differences in sire EPD that were exhibited in the progeny at USMARC and are used to adjust the breed differences estimated from USMARC data to the differences between animals in the breed born in 2007 (based on the 2007 breed average EPD). Using these adjusted breed differences, adjustment factors were calculated that can be added to breed association EPD to allow comparison of bulls from the 18 breeds (Angus, Beefmaster, Brahman, Brangus, Braunvieh, Charolais, Chiangus, Gelbvieh, Hereford, Limousin, Maine-Anjou, Red Angus, Salers, Santa Gertrudis, Shorthorn, Simmental, South Devon, and Tarentaise). This report details the calculations used for the annual update of the procedure first implemented in 1991. Changes for 2009 included a change to the model used to estimate breed differences in order to adapt to changes in the USMARC Germplasm Evaluation program and additional progeny weights on 14 breeds and grandprogeny weights on 9 breeds.