Performance of beef Guzerat and Guzerat-cross bulls during the feedlot, and carcass traits of Guzerat-cross groups

Abstract

Two experiments were conducted to evaluate performance and carcass traits of Guzerat-based beef bulls. In experiment 1, Guzerat; F1 Guzerat × Holstein (‘Guzholstein’); F1 Guzerat × Nellore (‘Guzonell’); and 1/2 Simmental + 1/4 Guzerat + 1/4 Nellore (Three-Cross) bulls (n = 12 each group) were kept in a feedlot for 84 days, receiving sorghum silage and concentrate supplement. ‘Guzholstein’ bulls had greater average daily gain (ADG; 1.7 kg/day) compared with ‘Guzonell’ (1.4 kg/day), but similar to Three-Cross and Guzerat (1.6 and 1.5 kg/day respectively). ‘Guzonell’ bulls gained less bodyweight (BW; 85.8 kg); however, the gain : feed ratio did not differ among groups. Dry matter intake (DMI) was less for Guzerat (11.8 kg) compared with other groups (12.4, 12.4, and 12.6 kg for ‘Guzholstein’, ‘Guzonell’, and Three-Cross respectively); DMI, as a percentage of BW, was lesser for Three-Cross bulls (2.5%) compared with other groups (2.7%, 2.8%, and 2.6% for Guzerat, ‘Guzholstein’, and ‘Guzonell’ respectively). In experiment 2, 18 bulls from experiment 1 were randomly selected from ‘Guzonell’, ‘Guzholstein’ and Three-Cross groups (n = 6, each breed group), transferred to a state-inspected slaughterhouse, and humanely slaughtered. Three-Cross bulls had greater carcass weight gain (80 kg), greater striploin yield (2.39%), and lesser leg yield (1.86%). ‘Guzholstein’ bulls had lesser dressing-out percentage and greater liver yield (51.6 and 1.28% respectively), whereas ‘Guzonell’ bulls had greater rump yield (1.47%). Forequarter yield, hindquarter weight and yield, eye round, flank steak, rump skirt, topside, rump cap, head, heart, lungs and trachea, spleen, tail, and tongue yield did not differ among groups. Despite the limited number of animals used in these experiments, we can conclude that all breed groups have potential for meat production because carcass traits meet the Brazilian beef industry standards, and ‘Guzholstein’ bulls could be an option for producers to diversify revenues.