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The objective of this study was to compare feedlot performance and carcass traits between two implant programs in heifers harvested at 3 different days on feed (DOF; 179, 200, or 221 d). Crossbred beef heifers (n = 3,084; 291 + 3.9 kg) were used in a 2×3 factorial arrangement of treatments in a randomized complete block design. Revalor-IH (80 mg TBA and 8 mg E2) was administered on arrival followed by Revalor-200 (200 mg TBA and 20 mg E2) 94 d before harvest (IH/200) or Revalor-XH (80 mg TBA and 8 mg E2, uncoated; 120 mg TBA and 12 mg E2, coated) was administered on arrival (XH). No implant × DOF interaction was detected (P ≥ 0.09) for any parameter. Heifers subjected to IH/200 had greater (P ≤ 0.01) final BW, ADG (P < 0.01) and G:F (P = 0.01). As DOF increased, BW increased (P ≤ 0.01) while ADG (P |
