F eedlot performance, carcass merit, and meat tenderness in crossbred cattle from Hereford, Braford, and Bonsmara sires and Angus and Brangus dams

The objective of this research was to evaluate the source and extent of tropical adaptation affecting feedlot and carcass traits. Calves of Brangus (BN) dams were sired by Braford (BFBN; n=63; 38% Brahman), Hereford (HEBN; n=38; 19% Brahman), and Bonsmara (BOBN; n=53; 19% Brahman and 31% Africander) sires. Calves of Angus (AN) dams were sired by Hereford (HEAN; n=38) and Bonsmara (BOAN; n=45; 31% Africander) sires. Carcass yield and LM area were greater (P<0.05) for HEBN compared with BFBN. Whereas BFBN had greater (P<0.01) backfat and empty body fat than the BOBN counterparts, the latter had greater (P<0.01) LM area. Contrasting HEBN and BOBN, HEBN were heavier (P<0.05) and fatter (P<0.05). However, BOBN were more heavily muscled (P<0.05) and deposited more internal fat (P<0.05). The BOAN steers were heavier (P<0.05) upon feedlot arrival than HEAN steers. Steers of Brangus (BN) dams were heavier (P<0.01), but steers of Angus (AN) dams exhibited greater (P<0.01) marbling scores. There were neither sire-breed nor dam-breed differences (P>0.15) in Warner-Bratzler shear force values. Presence of Brahman breeding (BN) in the dam breed positively affected weight traits, whereas absence of Brahman breeding (AN) positively affected carcass merit traits. In terms of sire breed contributions, neither extent nor source of tropical adaptation provided a distinct overall advantage in this study.