Abstract

Young bulls of five breed types [Brahman (n=4), F1-Angus (n=4), F1-Chianina (n=4), F1- Romosinuano (n=4), and F1-Simmental (n=4)] were fattened for 165 days on improved pastures (savanna ecosystem), to compare their performances in carcass traits and meat yield. The Brahmans had lighter shipping liveweight and carcass weight (P<0.01); their carcasses had more abundant fat cover than those of F1-Angus and F1-Simmental (P<0.05) and, like the F1- Romosinuanos, showed a younger "A" muscle maturity than the F1-Simmental (P<0.05). The F1-Romosinuano had the highest carcass dressing value (56.9%) and resulted with the largest ribeye area (76.4 cm2; P<0.01). By the USDA standards, all these entire males were considered "Bullocks" and graded USDA Standard, with USDA yield grade 1 or 2. The proportions of eye of round, inside round, shoulder clod and foreshank varied (P<0.10) by breed type. Brahman carcasses yielded 2.6% more trimmed fat than F1-Simmental carcasses (P <0.05). Under grassfeeding conditions, carcass quality in terms of marbling, exterior fat finish and physiological maturity does not appear to improve by crossing Brahman with European Bos taurus breeds while crossbreeding with Romosinuano is promising to improve body weight, carcass performance and ribeye area.