Angus and Angus-cross calves (632 lb) were
utilized in a finishing study to evaluate the
effects of implanting with estradiol and
progesterone (Synovex-S®) and(or) trenbolone
acetate (Finaplix®) on performance of finishing
steers. Over the entire finishing period (117 d),
implanted steers had higher (P<.05) daily gains
and were more efficient than nonimplanted
steers. Carcasses from implanted cattle had
heavier (P<.05) hot weights and larger
(P<.05) ribeye areas. Steers implanted with
Finaplix had larger (P<.05) ribeye areas than
those implanted with Synovex only. Marbling
scores and quality grades were not affected by
implant treatments. Rib (9-10-11) sections from
implanted steers were heavier (P<.05) as a
result of both heavier (P<.05) bone and soft
tissue weights. However, no differences in
percentages of protein, fat, and moisture were
detected by proximate analysis of the soft tissue.
Concomitant use of Finaplix with Synovex-S did
not affect performance of Angus and Anguscrossed
steer calves.
