PSIV-B-17 - Effects of Weaning Method on Performance of Crossbred Beef Calves

Abstract: English cross beef calves (n=115; BW = 245 + 40 kg) were used in the first of a three-year project to examine the effects of three weaning systems on post weaning performance. Cattle were stratified by age of dam and assigned to: 1) Drylot (DRY), 2) Pasture (PAST) or 3) Fenceline (FEN) weaning system. Calves in DRY were physically separated from their dams and fed a mixed ration across 4 pens. Calves in PAST were physically separated from their dams and assigned to 2 pastures consisting of Bermudagrass and fed a supplement. Calves in FEN were separated from their dams in adjacent pastures (n = 2) but maintained nose contact with their dams and fed a supplement. Pasture analysis from PAST and FEN were used to calculate the amount of supplement, so that total NE would be similar to that fed to DRY. Cattle were weighed weekly, until d 28, then weighed on d 56. Pen/pasture were the experimental unit, animal within pen was the random effect, data were analyzed using PROC Mixed. No differences (P > 0.10) were noted with BW at d 0, 7 or 28; however, both FEN and PAST had greater BW at d 15 (P = 0.05) and tended to have greater BW at d 21 (P = 0.06); nevertheless, by d 56, DRY had greater BW compared with FEN and PAST (P=0.03). Similarly, ADG tended to be greater in FEN and PAST from d 0-14 (P= 0.06) and from d 0-21 (P = 0.07). Overall ADG from d 0-56 was greater for DRY compared with PAST and FEN (P = 0.03). By design, cattle in DRY had more measurable DMI compared with PAST and FEN at all points (P < 0.0004). Cost of gain was greater (P= 0.02) with more economical gain associated with FEN and PAST compared with DRY (P = 0.02).