264 Using bermudagrass baleage to increase stocking rates of fall wheat pasture

摘要

The objectives of the current research were to determine the effect of offering ad libitum bermudagrass (Cynodon dactylon) round bale silage on performance and stocking rate of growing steers grazing wheat pasture in northern Arkansas. Eighteen, 1.6-hectare wheat fields were no-till planted to soft-red winter wheat in the first week of September (101 kg wheat seed/ha; cv. Jamestown) and were stocked to growing steers on October 23, 2018 at 2.5 steers/ha without bermudagrass baleage (CONTROL, n = 6) or with ad libitum bermudagrass baleage stocked at 2.5, 3.75, or 5.0 steers/ha (BALE2.5, BALE3.75, and BALE5.0, respectively; n = 4 pastures/treatment). The bermudagrass baleage was harvested in the late summer of 2018 and contained 40%DM, 14.3% CP, 70% NDF, 39% ADF, and 55% calculated TDN. Forage mass was 1,268 kg DM/ha (P ≥ 0.39) at the start of grazing and forage allowance (P < 0.01) was 2.25, 2.20, 1.62, and 1.27 kg forage DM/kg steer BW, respectively, at the start of grazing. Average daily gains of CONTROL (1.40 kg/d) did not differ (P = 0.36) from BALE2.5 (1.34 kg/d), but as stocking rate increased ADG decreased (P < 0.01) to 1.14 kg/d and 0.96 kg/d, for BALE3.75 and BALE5.0, respectively. As observed with ADG, gain per hectare and steer grazing-days per hectare did not differ (P ≥ 0.53) between CONTROL (340 kg/ha and 272 d/ha, respectively) and BALE2.5 (365 kg/ha and 272 d/ha, respectively), but each increased (P < 0.01) with increasing stocking rate, to 408 and 543 grazing d/ha for BALE3.75 and BALE5.0, respectively, and 467 and 524 kg BW gain/ha, respectively. The current research indicates that, even though individual animal performance decreases, stocking rates of wheat pasture for fall grazing stocker calves can be increased two-fold with up to 54% increase in BW gain/ha.