EFFICACY OF COMPUDOSE® AS AN ANABOLIC IMPLANT FOR GROWING-FINISHING FEEDLOT HEIFERS

A series of three trials was conducted to determine the effect of a controlled release silicone rubber implant containing 24 mg estradiol 17β (Compudose®) on the weight gain and feed efficiency of feedlot heifers. A total of 352 heifers with an average initial weight of 245 kg were used in the three studies. The heifers were fed a high roughage (corn silage or chopped brome alfalfa hay) grower diet followed by either a 75% barley (two trials) or 50% high moisture corn (one trial) finishing diet. Heifers implanted with Compudose® tended (P < 0.10) to have higher average daily gains (6.7%) and improved conversion of feed to liveweight gain (4.1%) compared to nonimplanted heifers. Mean carcass weight of implanted heifers was 5.0 kg heavier (P < 0.05) than control heifers. Fat thickness was 0.11 cm less (P < 0.05) and rib-eye area 3.6 cm2 larger (P < 0.05) in the Compudose® versus the control groups. Compudose was efficacious in improving carcass quality of growing and finishing feedlot heifers and resulted i...