Steer Performance and Pasture Productivity among Five Perennial Warm-Season Grasses

作者：Burns J C^*; Fisher D S

来源：Agronomy Journal, 2013, 105(1): 113-123.

DOI：10.2134/agronj2012.0142

Grazing systems in the mid-Atlantic region of the United States typically utilize perennial warm-season grasses. Bermudagrass [Cynodon dactylon (L.) Pers.] has served this function in the region, but the resulting animal performance has been modest. Steer and pasture performance of three native grasses, big bluestem (BBS) (Andropogon gerardii Vitman), eastern gamagrass (GG) (Tripsacum dactyloides L.), and switchgrass (SG) (Panicum virgatum L.), and an introduced Old World bluestem, Caucasian bluestem (CBS) [Bothriochloa bladhii (Retz.) S. T. Blake], were compared during 6 yr with Tifton 44 bermudagrass (BG) as the control. During summer (June-September), steers continuously stocked on the alternative grasses gained similarly (0.73 kg d(-1)) but more rapidly than those grazing BG (0.49 kg d(-1)). Stocking of BG at 9.9 steers ha(-1) was greater than the alternative grasses (5.7 steers ha(-1)), which were similar. Although animal days per hectare were greater for BG, weight gain per hectare was similar (mean = 357 kg ha(-1)) because of the differential gain per day. Canopies of BG and CBS had the least proportion of their mass in leaf (24.5 and 25.0%, respectively) compared with GG (58.2%), BBS (35.6%), and SG (30.9%), with the latter two similar. In general, any one of the grasses can serve as the warm-season component; however, pastures of BBS, GG, SG, and CBS would be more appropriate for growing ruminants, although at a reduced stocking rate, than BG. The latter would provide adequate forage for mature animals.

• 出版日期2013-2