Bulls vs… steers conventional and Russian castrates amd effects of stilbestrol
W. J. Clawson, University of California, Davis
Reuben Albaugh, University of California, Davis
Don Petersen, Merced County
California Agriculture 24(2):12-14. DOI: 10.3733/ca.v024n02p12.
W. J. Clawson is Extension Animal Scientist, University of California, Davis. Reuben Albaugh is Extension Animal Scientist Emeritus, University of California, Davis. Don Petersen is Farm Advisor, Merced County.
Two significant findings of this experiment were: (1) Russian castrates were intermediate between steers and bulls in all phases of production (preweaning and postweaning), although these differences were not significant; (2) nursing steer calves implanted with 30 mg stilbestrol, and again as they entered the feedlot for finishing, performed just as well as those that were implanted first upon entering the feedlot—however, the double-implant animals produced carcasses that were 33 lbs heavier (cold weight) than those that were implanted only once (indicating that the cow-calf operator, as well as the cattle feeder, can secure benefits from stilbestrol implantation). Bulls again outperformed steers and Russian castrates (substantiating recent reports by other researchers) in daily gain, carcass index, and cutability as well as feed efficiency.
Feedlot finishing at U.C. Davis was under the direction of William Garrett, Professor of Animal Science. Castrations were performed by Drs. John Kendrick, Professor of Veterinary Medicine, and George Crenshaw, Extension Veterinarian, U.C., Davis. Final USDA slaughter grades were determined by C. A. Santare, Supervisor, USDA Livestock Meat Grading Branch, San Francisco.