Starting Yearlings with Ramp in Southern Plains Feedlots

Three hundred six crossbred steers (703 ± 1 lb) were used to determine effects of adapting steers to a finishing diet using RAMP for 14 to 30 d on steer performance and carcass characteristics. RAMP treatments were compared to a traditional step-up procedure (CON) utilizing an initial concentration (DM-basis) of 32.5% steam-flaked corn (SFC), 45% alfalfa hay (ALF), 20% Sweet Bran, and 2.5% supplement (DM-basis). The CON steers were adapted to a finishing diet containing 65.7% SFC, 20% Sweet Bran, 8% ALF, 3% yellow grease, and 3.3% supplement (DM-basis) in 22 d. Adaptation procedures for CON included reducing ALF and increasing SFC, yellow grease, and urea. Steers receiving RAMP were adapted to the same finishing diet using RAMP for 14, 18, 22, 26, or 30 d. As the steers were adapted, the dietary level of RAMP was decreased and the finishing diet was increased. Compared with the CON, feeding RAMP improved ADG (4.19 vs. 4.38 lb/d; P = 0.06), increased carcass-adjusted final BW (1287 vs. 1314 lb; P = 0.05), and increased HCW (820 vs. 837 lb; P < 0.05). As the adaptation period for steers consuming RAMP increased from 14 to 30 days, fat thickness (P = 0.06) and YG (P =0.01) increased linearly. Adapting steers to a finishing diet using RAMP reduces the total amount of roughage by 21 to 28%, and increases animal weight gain during the entire finishing phase.