Effects of Lactational Status on the Performance and Carcass Composition of 30-month-old Heifers in the Single-calf Heifer System
نویسندگان
چکیده
Twenty-four Angus x Holstein heifers were utilized in the single-calf heifer system. Calves were weaned from one-half of the dams between d 64 and 89 postpartum. Dam’s were gradually adapted to a high concentrate diet over a four wk period at the beginning of the trial. Heifers that had their calves early weaned (EW) gained 44.2% faster (P < .01) and consumed 10.8% less (P < .05) DM than lactating (L) heifers. The EW heifers were 60.0% more (P < .01) efficient than L heifers. However, when calf performance was included with heifer performance, L heifers were 23.7% more (P < .05) efficient than EW heifers. The EW heifers had 18.9% heavier (P < .01) hot carcasses than L heifers. Backfat thickness was 1.07 and .66 cm (P < .01) for the EW and L heifers.
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