|Mayeux Jr, Herman|
Submitted to: American Society of Animal Science Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 2005
Publication Date: July 24, 2005
Citation: Phillips, W.A., Coleman, S.W., Riley, D.G., Chase, C.C., Mayeux, H.S. 2005. Postweaning performance of purebread Angus and Romosinuano steers [abstract]. American Society of Animal Science Annual Meeting. 88(1):327. Interpretive Summary: ABSTRACT ONLY
Technical Abstract: The objective of this study was to compare stocker and feedlot performance of purebred Angus and Romosinuano steers born and reared in a subtropical environment (Florida) and shipped to a more temperate environment (Oklahoma) for growth and finishing. A total of 160 steers were evaluated over two production cycles. Steers were born (January through March) and reared in central Florida, weaned in the fall and shipped (1900 km) for growth and finishing in central Oklahoma. Steers grazed annual cool season grasses (primarily Triticum aestivum) and were managed as a single group during the winter (125 d) and spring (84 d) stocker phases. Angus and Romosinuano steers had similar BW upon arrival (193 kg ± 3.5). During the winter stocker period, Romosinuano steers gained less (P < 0.05) BW than Angus steers (75.9 vs 102.2 kg). Gains in BW during the spring grazing season were similar between the two breeds, but Romosinuano steers had lower (P < 0.05) total stocker gains (118.3 vs 143.8 kg) than Angus steers. In June of each year, steers were blocked by breed and randomly assigned to a conventional confinement or a grain-on-grass (GOG) finishing system. In the GOG system, steers were finished on bermudagrass pasture using a combination of an intensive stocking rate (9 steers/ha) and ad libitum access to a high energy diet in a self-feeder. Under the conventional system, carcass marbling scores and quality grades were not different (P > 0.10) between the two breeds. However, the GOG Angus steers produced carcasses that had higher (P < 0.01) marbling scores and quality scores than Romosinuano GOG steers. Under conventional confinement feeding, Romosinuano steers had lower (P < 0.10) DMI than Angus steers, but feed efficiencies were similar. When compared to Angus steers, Romonsinuano steers had lower ADG during the stocker phase, but were as efficient as Angus steers during the finishing phase when fed under a conventional confinement feeding system.