Effect of Anabolic Agents on Marbling in Yearling Crossbred Steers

A total of three hundred and twenty-four crossbred yearling steers were used in a two year study to determine the effects of anabolic agents on carcass characteristics. Steers were fed in a commercial feedlot for an average of 123 days, slaughtered and carcass data were collected. Implanted cattle gained significantly more weight (P\u3c .05) than nonimplanted cattle. Steers that were implanted with Revalor-S gained weight more rapidly (P\u3c.05) than Synovex-S implanted cattle. Implants significantly (P\u3c.05) increased hot carcass weights and rib eye area when compared to nonimplanted cattle and Revalor implanted cattle tended (P= .0564) to have heavier hot carcass weights than Synovex implanted cattle. lmplants did not significantly affect yield grades. Implanted steers had lower (P\u3c .05) marbling scores than control steers. Steers that were implanted with Revalor showed a significant (P\u3c.05) decrease in marbling score when compared to the Synovex groups. The percentage of choice carcasses for no implant, Revalor, and Synovex treatments were 78.85, 58.82, and 67.68, respectively