Steer Performance from Two Perennial PennisetumSpecies, Switchgrass, and a Fescue—‘Coastal’ Bermudagrass System¹

Abstract

Subtropical perennial grasses make important contributions to productive, season-long grazing systems in the USA. The perennial bermudagrasses, particularly 'Coastal' bermudagrass (C}'nodon dac-t}'lon (L.) Pers.), are extremely productive, but high fiber allows only poor to moderate animal performance. Steer average daily gains (ADG) and productivity estimates of the subtropical perennials Oaccidgrass (Penni.retum flaccidum Griseb.), P. orientak Rich., and switchgrass (Panicum virgatum L.) were obtained. Sequential grazing of tall fescue (Festuca arundinacea Schreb.) and Coastal as a system (F + C) served as the standard for comparison. The grazing experiment with yearling steers was conducted on a Typic Hapludult soil for 3 years. Calendar days grazed, ADG (kg) and steers ha-1 , respectively, from initiation of grazing until Coastal was stocked (period 1) averaged 53, 0.93, and 15.1 for tall fescue; 20, 1.35 and 11.1 for Oaccidgrass and 40, 1.07, and 8.9 for switchgrass. Number of steers ha-1 was greatest on tall fescue and ADG lowest (P ::5 0.06). Flaccidgrass supported significantly more animals than switchgrass. Summer (period 2) results (avg. 98 days) for ADG and steers ha-1 , respectively, were 0.43 and 25.1 for Coastal; 0.78 and 9.1 for Oaccidgrass (P. orientak was similar), and 0.92 and 7.9 for switchgrass. Steer ADG was lowest and steers ha-1 highest on Coastal, while the other grasses were similar for both. Tall fescue made little contribution because rainfall was below normal all 3 years. Seasonal results from the F + C showed most calendar days (160), lowest ADG (0.59) but similar numbers of steers ha-1 (9.5) compared with respective values of 130, 0.90, and 9.6 for Oaccidgrass and 140, 0.96 and 8.2 for switchgrass. Flaccidgrass averaged significantly more steers ha -I than switchgrass. Gain ha -I from tall fescue in period 1 (792 kg) and Coastal in period 2 (1160 kg) was greater than the average for the other grasses, 349 and 559 kg, respectively. However, seasonal computations based on combined land areas for the F + C system yielded 1010 kg of gain ha-1 • That gain did not difl'er from the 930 kg ha-1 for the other grasses, even though the F + C system averaged 25 more calendar days. Flaccidgrass and switchgrass have quality attributes and a sufficiently long growing season to make an important contribution to an animal enterprise that values large daily animal responses. Coastal is more appropriately used in enterprises for an animal class, or portion of the season, where only moderate to low response animai-1 is required.AdditioiUil index words: Forage quality, Available forage, Stand persistence, Gain ha-1 , Total digestible nutrients ha-I, Panicum virgatum L., Penniaetum flaccidum Grise b., Penniaetum orientale Rich.

Switchgrass for forage and bioenergy: harvest and nitrogen rate effects on biomass yields and nutrient composition

“…At this stage, we found the harvested biomass to be 5.8% crude protein, 73.4% NDF, and 58.7% digestible dry matter on average across locations (Table 3). Crude protein concentrations below 7% of dry matter limit ruminal fermentation of forages and do not meet minimal protein requirements of growing animals (Burns et al 1984). Intake of forage also may be restricted at such high NDF concentrations (Ball et al 2001).…”

Economic Feasibility of Using Switchgrass Pasture to Produce Beef Cattle Gain and Bioenergy Feedstock

“…In addition to its agronomic potential as a bioenergy feedstock crop, a number of studies report that grazing early growing switchgrass produces good beef cattle gain. For instance, Burns, Mochrie, and Timothy [16] reported that switchgrass pastures evaluated in North Carolina maintained a long growing season and had a valuable impact on average daily gain. Mosali et al [17] reported average daily gains ranging between 0.83 and 1.05 kg hd −1 for stocker cattle grazing between early April and late May.…”

Potencial Produtivo De Uma Pastagem Nativa Do Rio Grande Do Sul Submetida a Níveis De Oferta De Forragem

“…Diferentes PP condicionam diferentes quantidades de MS/ha ou resíduo de MS aérea. Com a redução na PP tem-se maiores resíduos (BURNS et al, 1984;ESCOSTEGUY, 1990;MORAES, 1991). Esta condição afeta a taxa de crescimento da pastagem e sua conseqüente produção de MS (KORTE et al, 1987).…”