COMPARISON OF HOLSTEIN, CHARBRAY, AND ZEBU BULLS FOR BEEF-PRODUCTION UNDER ROTATIONAL GRAZING - II - OFFAL COMPONENTS AND CARCASS COMPOSITION

After two complete grazing trials, 47 Holstein, Charbray and Zebu (mos tly Brahman) bulls were processed for offal components, carcass traits and composition comparisons at an average liveweight (LW) of 545 kg. At the same LW the Holstein bulls had a significantly higher (P < 0.05 ) weight for the head (3.33% of LW), feet (2.47% of LW), liver (1.11% of LW), kidneys (1.29% of LW) and intestines (5.18% LW) than the Zebu and Charbray bulls, and a significantly longer leg (53.0 vs. 48.90 cm; P < 0.05) than the Charbray bulls. The Zebu bulls had the heaviest hi de (P < 0.05) and smallest stomach weight (P < 0.05). The carcasses of the Holstein bulls had a significantly higher (P < 0.05) bone percent age (21.60 vs. 16.63, 17.46%) and a lower amount of fat than the Charb ray and Zebu bulls, respectively. Charbray bulls presented greater loi n eye area, total amount of muscle, muscle to bone+fat ratio and weigh t and percentage of the Biceps femoris, Gluteus, and Cuadriceps femori s muscles in the left-hindquarter (LH), than the Zebu and Holstein bul ls (P < 0.05). Charbray and Zebu bulls showed greater (P < 0.05) thick ness of the round (26.03, 25.85, vs. 24.03 cm), hot carcass and LH wei ght, total dissectible fat, dressing percentage, muscle to bone ratio, and weight of the Semimembranosus, Psoas major, Longissimus dorsi and Semitendinosus muscles than the Holstein bulls (P < 0.05). No signifi cant differences (P > 0.05) were found among breeds for subcutaneous f at thickness and for the weights of fascia/tendon, trimming, carcass s hrinkage, and for the forequarter weight and percentage of left side.