Stocker Cattle Performance from Grazed Mixtures of Triticale and Wheat with Ryegrass

Abstract

Previous research indicates that beef production from winter grazing in the lower Gulf Coast region is typically greater from monocultures of ryegrass (Lolium multiflorum) and wheat (Triticum aestivum) than triticale (× Triticosecale); how-ever, little information is available on beef production from mixtures of these species. For this reason, we conducted a 2-yr experiment to evaluate triticale (T; var. ‘Tri-cal 2700’), wheat (W; var. ‘SS 8641’) and ryegrass (RG; var. ‘Marshall’) in mixtures as winter forage for grazing beef cattle. Replicate 1.42-ha paddocks of T + RG, W + RG and T + W + RG (2 paddocks/ treatment) were planted on November 30, 2012 (Yr 1) and November 4, 2013 (Yr 2), and were initially stocked with 4 yearling crossbred steers (mean initial BW, 357 kg) per paddock on January 29, 2013 (Yr 1) and December 16, 2013 (Yr 2). Forage allowance was maintained at a target value of 1 kg DM/kg steer BW utilizing an adjustable stocking density by the put-and-take method. Forage mass and nutritive value were determined by clipping eight 0.25-m2 quadrats per paddock prior to grazing and at subsequent 2-wk intervals throughout the duration of the experiment. Grazing was discontinued in Yr 1 on May 24, 2013 (116 d) and in Yr 2 on May 5, 2014 (141 d) when forage mass and quality were no longer able to support an ADG 0.90 kg. Data were analyzed as a completely randomized design by the PROC MIXED procedure of SAS 9.2, and forage metrics and chemical composition determined at each sampling period were treated as repeated measures. Suboptimal early-season growing conditions in Yr 2 contributed to decreased mean for-age mass (P < 0.001) and stocking density (P = 0.003) compared with Yr 1. Across both yr, mean forage mass (1,093 kg DM/ha), forage allowance (0.89 kg DM/kg steer BW) and grazing-d/ha (375) did not differ (P > 0.10) among treat-ments, and there were no differences (P > 0.10) among treatments in steer ADG (1.45, 1.49 and 1.39 kg/d for T + RG, W + RG and T + W + RG, respectively). Mean forage IVDMD (90.9%) and concentrations of CP (19.5%) and ADL (1.2%) were not different (P > 0.10) among treatments. Results indicate that binary mixtures of W and T with RG were comparable, and the ternary mixture offered no advantage over binary mixtures, for beef production from winter-grazing of these forage species.