Effect of 300 or 400 mg Daily of Ractopamine Hydrochloride on Growth Performance and Carcass Characteristics of
Finishing Steers During the Last 14, 28, or 42 Days
The effects of ractopamine hydrochloride (Optaflexx®) dosage (0, 300, and 400 mg/head/day) and duration (14, 28, or 42 days) on growth performance were evaluated in feedlot finishing diets. Feeding 300 mg of Optaflexx for 28 or 42 days increased live final BW by 13 and 29 lb, while feeding Optaflexx at 400 mg resulted in 27 or 24 lb increases relative to 0 mg steers, respectively. Feeding 300 mg of Optaflexx for 28 or 42 days would suggest 11.1 or 16.6 lb improvements in HCW, while feeding 400 mg of Optaflexx would suggest 19.7 or 20.7 lb heavier carcasses compared to steers fed 0 mg Optaflexx, respectively