287 Effect of corn or barley in feedlot diets, on steer performance and feeding behavior
Abstract This study evaluated the effects of barley and corn finishing rations on feedlot performance and feed intake behavior of steer calves. For 2 consecutive years, Angus-based steer calves were fed and finished at the Northern Agricultural Research Center in Havre, MT. Steers averaged 427 kg (n = 48) in year 1 and 407 kg (n = 47) in year 2. Feedlot rations used in this study were comprised of 1) corn or 2) Hockett barley. Diets were balanced to be isonitrogenous (12% CP). Steers were fitted with an electronic identification ear tag and fed in a GrowSafe system to measure individual animal intake and behavior. Initial and final unshrunk weights were obtained on two consecutive days and averaged. Weight gain, ADG, and G:F were measured for each steer. Feeding behavior including: time spent eating (min∙day-1), visits per day, time per visit (min), eating rate (g∙min-1), intake (kg∙day-1), and intake per visit (g) were also measured for each individual. Average daily gain, final live weight, DM intake, hot carcass weight, marbling, and REA all had significant year effects (P < 0.05.). Corn-fed steers had heavier hot carcass weights (P = 0.01), and greater average daily gains (P = 0.04); however, corn-fed steers also had higher average daily DMI (P = 0.02) than barley-fed steers. Carcass weights were on average 15.89 kg heavier for steers fed corn compared to steers fed barley (P = 0.02) and corn-fed steers displayed higher numerical yield grade (P = 0.02). There were no treatment effects observed for final live weight, gain to feed, marbling, fat, REA, time spent eating, visits per day, time per visit, eating rate or intake per visit (P ≥ 0.05). In summary, barley-fed steers yielded comparable performance outcomes as corn-fed steers, thus, depending on cost and production year, barley could be a potential high-quality feed source in beef cattle finishing rations.