ARS | Publication request: Steer Performance and pasture productivity of a tall fescue-bermudagrass system compared with yellow bluestem and coastal panicgrass

Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 1, 2012
Publication Date: June 1, 2012
Citation: Burns, J., Fisher, D.S., Pond, K.R. 2012. Steer Performance and pasture productivity of a tall fescue-bermudagrass system compared with yellow bluestem and coastal panicgrass. Professional Animal Scientist. 28:272-283.

Interpretive Summary: In year-round grazing systems, improvement in the quality of the warm-season component would be advantageous because it would improve potential productivity and profit. The warm-season perennials, Yellow bluestem (YBS) and Coastal panicgrass (CPG) were compared with bermudagrass as part of a Tall fescue-bermudagrass system. The use of YBS resulted in no advantage in ADG over bermudagrass, but an increase was obtained for CPG. However, neither YBS nor CPG could be stocked as heavily as bermudagrass and consequently, were inferior to the productivity per unit land area of bermudagrass pasture. Furthermore, continuous stocking of CPG pasture severely weakened stands after the second year of stocking. Stand losses were not evident for YBS. The potential of CPG for use in grazing systems needs to be further explored. This might be addressed through the use of some form of rotational stocking or perhaps used in a 2 to 3 year rotation with other crops.

Technical Abstract: Year-round grazing in animal production systems has potential in the mid-Atlantic USA. Tall fescue [Lolium arundinaceum (Schreb.) S. J. Darbysh.] is generally the cool-season perennial and bermudagrass [Cynodon dactylon (L.) Pers.] the warm-season perennial in these systems. This study evaluated yellow bluestem (Bothriochloa ischaemum L.) (YBS) and Coastal panicgrass (Panicum amarum var. amarulum) (CPG) for their quality and productivity with a tall fescue-bermudagrass system (BGS) as a control. Steer ADG (kg/d) was less (P = 0.05) in the BGS (0.66) than the mean of 0.77 from YBS (0.68) and CPG (0.86) which differed (P = 0.02). Steer ADG (kg/d) in spring (0.95) was greater (P < 0.01) than summer (0.53) but pasture species interacted with season (P = 0.02). The ADG of CPG was stable across season (from 0.97 to 0.76 kg/d), whereas BGS or YBS declined from 0.97 and 0.92, respectively, to 0.37 and 0.49 kg/d. Dietary in vitro true organic matter disappearance was similar among species (P = 0.29) and seasons (P = 0.62) averaging 803 g/kg, however DMI (kg 100-^1 kg BW d-^1) was least (P = 0.05) from the BGS (2.64) compared with YBS (2.97) and CPG (3.40) (P = 0.09). The BGS was stocked greater (P < 0.01) at 12.3 compared with 6.2 and 4.9 steers/ha for YBS and CPG, respectively. Adjusting for days tall fescue was grazed (23%) still favored the BGS. No difference in steer gain (P = 0.95) and effective feed units (P = 0.54) occurred between YBS and CPG (473 and 2754 kg/ha).