Effect of growth promotant implants on liveweight change, wool and carcass characteristics of mature wethers grazing dry season pastures

Summary. Thirty-two mature recently shorn wethers (mean liveweight 52.1 kg) were implanted with 1 of 4 different hormonal growth promotants (Ralgro, Compudose, Revalor-S and Synovex-H) to determine animal production responses on dry season pastures. The wethers were grazed for a period of 135 days on dry season native Mitchell grass (Astrebla spp.) pastures infested with Acacia nilotica. The wethers were weighed monthly. Four months after commencement of the experiment, the wethers were shorn to determine wool characteristics (micron, yield and staple length). At 2 weeks post-shearing the wethers were slaughtered to determine carcass attributes. Serial rumen ammonia concentrations indicated that diet quality was declining throughout the experiment. Relative to the controls, the Compudose implant had increased (P