LIMIT-GRAZING OF WINTER WHEAT PASTURE TO INCREASE STOCKER PRODUCTIVITY

Authors: Phillips, William; Coleman, Samuel; Riley, David; Chase, Chadwick; Mayeux Jr, Herman

Submitted to: American Society of Animal Science Southern Section Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 11/2/2005
Publication Date: 2/4/2006
Citation: Phillips, W.A., Coleman, S.W., Riley, D.G., Chase, C.C., Mayeux, H.S. 2006. Limit-grazing of winter wheat pasture to increase stocker productivity [abstract]. Proceedings of American Society of Animal Science Southern Section Meeting, February 4-8, 2006, Orlando Florida. p. 53.

Interpretive Summary: Abstract Only

Technical Abstract: The crude protein concentration of winter wheat forage is about twice that needed for growth and development of stocker calves. Balancing energy and N intake by limit-grazing wheat pastures and providing supplemental high energy feed could decrease the wastage of forage N and increase the carrying capacity of winter wheat pastures. The objective of this experiment was to measure performance of stocker calves under a grazing management strategy that limited wheat forage intake. Steers born at Brooksville, FL were weaned in the fall and transported to El Reno, OK. Calves (n = 479) were purebred Angus, Brahman or Romosinuano or reciprocal crosses. Each year (n = 3), calves were blocked by breed, and randomly assigned to one of four wheat pastures for the winter phase (120 d; Nov. to Mar.). Two pastures were grazed continuously (Control) and two pastures were grazed half of the time (Limit-grazed). Calves in the Limit-grazed groups were placed in pens three times weekly for 28 h to limit access to wheat pasture by 50% and were fed 5 kg DM/calf of a mixed ration (9% CP, 2.25% fat, 19% fiber) and given ad libitum access to warm-season grass hay. In mid-March, calves from one of each treatment group were combined and grazed wheat forage continuously for 50 d (spring phase). Data were analyzed using a mixed model with breed of calf, grazing management, and the two-way interaction. Initial BW was 251 kg at the beginning of the winter phase. Individual calf performance was similar (p > 0.10) between the Limit-grazed and Control groups during the winter (0.68 vs. 0.73 kg) and spring (1.23 vs. 1.15 kg) phases. Limit-grazed calves gained 0.14 kg for each kg of supplemental fed during the winter phase. Limit-grazing of wheat pasture to reduce wheat forage intake resulted in increased carrying capacity and greater stocker gain per ha than continuous grazing management.