EFFECTS OF ACREMONIUM-COENOPHIALUM INFESTATION, BERMUDAGRASS, AND NITROGEN OR CLOVER ON STEERS GRAZING TALL FESCUE PASTURES

Performance of cattle grazing tall fescue (Festuca arundinacea Schreb.) is depressed when the grass is infested (E+) with the endophytic fungus Acremonium coenophialum Morgan-Jones and Gams. Steer performance can be improved when clover (Trifolium spp. L.) is overseeded into tall fescue pastures, and beef production/acre can be increased when bermudagrass [Cynodon dactlyon (L.) Pers.] is grown in combination with tall fescue. The objective of this study was to compare effects on steer performance of including ladino clover (T. repens L.), 'Midland' bermudagrass, or a combination of both in E+ and noninfested (E-) tall fescue pastures. Three tester steers (Bos taurus L.) per pasture grazed between April and September from 1983 through 1985. Additional cattle were used in a modified put-and-take management system to maintain similar quantity and quality of forage among pastures. Forage growth and consumption were measured by cage-and-strip methodology. Pastures with bermudagrass treatments averaged 18 and 53% bermudagrass in spring and summer, respectively. Clover content of pastures overseeded with clover was variable among treatment combinations and years and ranged from 6 to 53%. Greater average daily gains (ADG), beef production per acre, and forage dry matter consumption, and lower rectal temperatures and hair coat scores, were observed when cattle grazed E- rather than E+ tall fescue. Steer ADG was higher on E+ pastures when bermudagrass was present. Clover was equally effective in increasing ADG on E+ and E- tall fescue pastures. Bermudagrass and clover were both effective in improving steer performance and/or production on both E+ and E- tall fescue. Additionally, bermudagrass reduced somewhat the detrimental effects of E+ tall fescue.