Technical Abstract: Three experiments were conducted to determine the influence of the endophytic fungus in tall fescue pastures and calf genotype on the performance of steers in the feedlot. In Exp.1 and 2, Angus steers grazed fescue pastures in Georgia containing low-, moderate-, or high-endophyte infestations. Steers were transported to Texas in October (Exp. 1) and July (Exp. 2), fed a 93% concentrate diet, and slaughtered at a backfat thickness of 12 mm. In both trials, dry matter intake and carcass characteristics were not affected (P>0.05) by endophyte infestation. Feedlot ADG and gain:feed increased as the previous pasture endophyte infestation increased (P<0.05). Serum cholesterol concentrations tended (P<0.10) to decrease with increasing endophyte infestation. In Exp. 3, Angus and Brahman x British crossbred steers grazed fescue pastures in Georgia containing low-, moderate-, or high-endophyte. Steers were transported to Texas in late August and fed a finishing diet. As endophyte infestation increased, serum urea N concentrations and gain:feed ratios increased (P<0.05), whereas initial BW, transit shrink (kg), serum cholesterol concentrations, final BW, and carcass weights decreased (P<0.05) in both breed groups. As endophyte infestation increased, arrival rectal temperatures increased (P<0.05) in Angus steers but not in Brahman- cross steers. Results of these studies are interpreted to indicate that the adverse effects of high-endophyte infestations in fescue pastures can carry-over to the feedlot for approximately 14 d. However, steers from infested pastures can compensate for poor pasture performance with improved performance in the feedlot when no adverse health effects occur. Any impact of the endophyte seems to be similar in Brahman-cross and Angus steers.