Comparison of Two Weaning Dates and Two Finishing Systems on Feedlot Performance, Carcass Characteristics, and Enterprise Profitability of Fall-born Steers1

In a 3-yr study, 139 fall-born steers (Angus and Angus x Charolais; BW = 287 ± 31 kg in mid-April) were allotted to 1 of 4 treatments in a 2 x 2 factorial arrangement. Weaning date treatments were 1) mid-April at 212 ± 12 d of age (normal weaning; NW) and 2) mid-July at 300 ± 15 d of age (late weaning). Finishing system treatments were feedlot placement in 1) July, with a mean calf age of 310 ± 14 d (calf-fed; CF), and 2) October, with a mean calf age of 394 ± 15 d (yearling-fed; YF). Steers assigned to the NW treatment were returned to native tall grass prairie rangeland after weaning each year. Steers assigned to the YF treatment grazed abundant native tall grass prairie pasture for an additional 84-d period. The number of days on feed was greater (P < 0.01) for CF compared with YF. Late-weaned steers were 16 kg heavier (P < 0.01) at the time of feedlot entry compared with NW steers. No other differences (P > 0.05) for time of weaning were detected, nor were there any interactions (P > 0.05) between weaning and finishing system. Yearling-fed steers were heavier (34 kg; P < 0.01) at the time of feedlot placement, had greater (P < 0.01) DMI, and had greater (P < 0.01) feedlot ADG (1.80 vs. 1.68 kg) than CF, resulting in greater final BW and hot carcass weight (P < 0.01). No other differences (P > 0.05) were detected for any carcass traits measured. System economic analysis showed no differences in break-even selling price or system profitability.