estradiol, trenbolone acetate, steers
Ninety crossbred yearling steers (818 ± 19 Ib) were utilized to evaluate the influence of implant treatment and days on feed on carcass characteristics and feedlot average daily gain (ADG). Treatments included no implant (C), implanted with Synovex-S on day 1 and Synovex-S on day 60 (SS) and implanted with Synovex-S on day 1 and with Synovex-S and Finaplix-S on day 60 (SSF). Ten steers from each treatment were slaughtered after 120, 134 or 148 days on feed. Implanting increased (P< .0001) ADG 18.9% and hot carcass weight (HCW) 6.4%. However, interactions between treatment and days on feed were significant (P<.05) for ADG and HCW. No other interactions were apparent. Rib eye area (REA) was 4.7% greater (P<.05) for implanted steers as compared to nonimplanted controls (13.72 vs 13.11 in.2). ADG (P<.12), HCW (P<.10) and REA (P<.05) were greater for steers implanted with SSF as compared to steers implanted with SS (3.90 vs 3.75 Ib, 846 vs 831 Ib, and 14.06 vs 13.38 in. , respectively). Marbling score (5.00 = Small°) tended (P<.16) to be lower for implanted steers compared with nonimplanted controls (5.54 vs 5.77 units). Marbling score was slightly (P<.16) lower for cattle implanted with SSF as compared to cattle implanted with SS (5.40 vs 5.67). Predicted days required to reach 75% low choice were 113, 124 and 138 for C, SS and SSF, respectively.
Number of Pages
South Dakota State University
Copyright © 1991 South Dakota State University.
Wagner, J. J. and Pritchard, R. H., "Combinations of Synovex¹ and Finaplix² for Yearling Steers" (1991). South Dakota Beef Report, 1991. 15.