CRAMBE MEAL IS EQUIVALENT TO SOYBEAN-MEAL FOR BACKGROUNDING AND FINISHING BEEF STEERS

Growth, feed efficiency, and carcass characteristics of 70 crossbred s teers fed one of four diets were compared. The four diets differed in source of protein supplementation: 100% soybean meal (SB), 67% SB and 33% crambe meal (CM), 33% SB and 67% CM, and 100% CM. All supplements were fed in isonitrogenous amounts. Steers were fed backgrounding diet s (12.9% CP) for 84 d and finishing diets (11.2% CP) for 96 d. Average initial weight was 303.4 kg. Backgrounding gains ranged from 1.38 to 1.41 kg/d (P = .92). Finishing gains ranged from 1.43 to 1.47 kg/d (P = .86). Range in entire-experiment gains was 1.41 to 1.46 kg/d (P = .8 5). Feed efficiencies were equal; entire-experiment efficiencies avera ged .144 (P = .96). Growth and efficiency patterns were the same for a ll four treatments. No overall treatment differences were detected for the seven carcass variables (P = .26 to .96). Average fat depth, long issimus muscle area, yield grade, and dressing percentage were .95 cm, 84.0 cm2, 2.45, and 61%, respectively. At the protein percentage leve ls of these diets, CM substituted equally for SB for growth rate, feed efficiency, and carcass characteristics.