Weight Gain in Suckling Calves Following Revalor-G®, Ralgro™, or Synovex®-C

Abstract

This study is the first report designed to compare approved estrogenic implants Ralgro™ and Synovex®-C with Revalor-G® in suckling calves. An on-farm comparison of the BW gain response following implantation was conducted using 156 native, commercial crossbred suckling steers (with similar genetics) on typical Mississippi fescue-based cow/calf operations. Calves were weighed (avg. 133.0 kg), randomized, and allocated to one of the three treatments. The calves which ranged from 2 to 4 mo of age were returned to their dams following routine processing and weighed again (236.2 kg) at 111 d (overall BW gain was 103.3 kg). Least square means for Revalor-G and Ralgro were not significantly different for BW gain and ADG (105.8/0.96 and 104.7/0.95, respectively). However, both Revalor-G and Ralgro significantly improved BW gain total and rate over Synovex-C. Although not currently approved for use in suckling calves, Revalor-G was comparable to Ralgro as a suckling-calf growth modifier.