Effect of Ractopamine Hydrochloride on Growth Performance and Carcass Traits in Calf-Fed and Yearling Holstein Steers Fed to Slaughter

Abstract

Five studies using 2,105 calf-fed and yearling Holstein steers were conducted to evaluate the effects of ractopamine hydrochloride (RAC) on performance and carcass characteristics when fed for the final 28 to 38 d of the finishing period. In 4 calf-fed Holstein studies, RAC was incorporated to achieve intakes of approximately 0 (control), 200, and 300 mg/steer daily. In the yearling Holstein study, RAC was fed at 0 or 200 mg/steer daily. Each study consisted of 4 to 14 pens/treatment with 4 to 72 steers/pen, depending on study site. In the 4 calf-fed Holstein studies, ADG was increased (P 0.05) were noted in any carcass trait measurements. These data demonstrate that RAC improves growth performance, hot carcass weight, and LM area in both calf-fed and yearling Holstein steers while having a minimal impact on quality grade.