CASE STUDY: Productivity, quality characteristics, and beef cattle performance from cool-season annual forage mixtures

A grazing experiment was conducted to quantify productivity, quality characteristics, and beef cattle performance from mixtures of oat (Avena sativa L.) and ryegrass (Lolium multiflorum L.; O-RG), rye (Secale cereale L.) and ryegrass (R-RG), or oat and rye and ryegrass (O-R-RG) under continuous stocking. Six 1.42-ha paddocks were seeded with O-RG, R-RG, or O-R-RG mixtures (2 paddocks/treatment) in November 2008 and stocked initially with 3 yearling crossbred test steers (392 ± 31 kg initial BW) per paddock on January 8, 2009. Forage mass and nutritive quality were determined by clipping 0.25-m2 quadrats (8/paddock) before the beginning of grazing and every 2 wk during the experiment. Stocking densities were adjusted using put-and-take steers to maintain grasses in a vegetative state, and grazing was discontinued on May 28. Data were analyzed as a completely randomized design by the PROC GLM procedure of SAS. Steer ADG was greater (P < 0.10) for O-RG (1.39 kg/d) and O-R-RG (1.26 kg/d) than R-RG (1.13 kg/d). Number of steer-grazing-days was 547, 655, and 625 d for R-RG, O-RG, and O-R-RG, respectively, and mean forage allowance across all treatments was 1.06 kg DM/ kg steer BW over the 140-d grazing experiment. Results indicate that O-RG was superior to R-RG for supporting beef cattle performance under continuous stocking, and that inclusion of rye in a ternary mixture did not improve performance over that from O-RG.