Production and Economic Efficiencies of Intensified Cow-calf Production Management Systems

The effect of calf weaning age on cow and calf performance and feed utilization was investigated over 2 yr. Multiparous, crossbred, lactating beef cows (n = 156) with summer-born calves were blocked by prebreeding BW, stratified by calf age, and assigned randomly to 1 of 4 treatments within strata. The experiment was a randomized complete block design with a 2 × 2 factorial arrangement of treatments with three replications (pens) per treatment per year (total n = 24). Factors were: 1) location; Agricultural Research and Development Center (ARDC) or Panhandle Research and Extension Center (PHREC) and 2) calf weaning age; early-weaned (EW) at 91 ± 18 d of age or conventionally weaned (CW) at 203 ± 16 d of age. All cows and calves were fed a common diet from early to conventional weaning time within each yr and location. Cows with weaned calves were limit-fed (6.9 kg DM/cow daily) while EW calves were offered ad libitum access to feed (4.0 kg DM/calf daily). Nursing pairs were fed an equivalent amount of DM (10.8 kg/pair daily). Initial cow BW and BCS were similar (P ≥ 0.26), but BW change from early to conventional weaning was 17 kg greater (P ≤ 0.01) for EW cows. Cow BCS and conception rates were not impacted (P ≥ 0.38) by weaning. Calf BW at conventional weaning was greater for CW than EW at ARDC, but greater for EW than CW calves at PHREC. Calf ADG per unit of total feed energy intake was greater for nursing pairs at ARDC, but not different between EW and CW at PHREC indicating early-weaning may have minimal effect on reducing feed energy requirements.