J. P. Schoonmaker,
F. L. Fluharty,
T. B. Turner,
D. M. Wulf,
S. J. Moeller,
S. C. Loerch 1
The Ohio State University Department of Animal Sciences
Sixty-seven Angus - Simmental crossbred steers (initial BW 341.3 ± 13.7 lbs) were used in a 2x2 factorial experiment to determine the effects of weaning age and implant regimen on growth and carcass characteristics. Steers were either early-weaned at an average age of 113 d (EW) or normal-weaned at an average age of 204 d (NW), and allotted by weight to an aggressive (A) or nonaggressive (NA) implant regimen. EW-A and NW-A steers were implanted with Synovex-C at an average age of 163 d, and Revalor-S at an average age of 204 d, and 295 d if BW was < 1,050 lbs. EW-NA and NW-NA steers were implanted with Synovex-S at an average age of 204 d, and 295 d if BW was < 1,050 lbs. Steers were penned individually and fed an 85% concentrate, 12.4% CP finishing diet. Steers were slaughtered when they reached 1,205 lbs. There were no differences (P > 0.37) in carcass characteristics or final empty body composition between EW and NW treatments. Yield grade (P < 0.08) tended to be lower for A vs. NA (3.5 vs. 3.8, respectively), but no difference (P > 0.81) existed for quality grade. Placing early-weaned calves on an aggressive implant regimen is a viable management option.
1For more information, contact at: The Ohio State University, Ohio Agricultural Research and Development Center, 114 Gerlaugh Hall, 1680 Madison Avenue, Wooster, OH 44691; 330-263-3903; e-mail: loerch.1@osu.edu