Hereford (n = 48), Senepol (n = 42), and reciprocal crossbred (n = 34) heifers from two consecutive calf crops were stratified by breed, age, and BW to receive bahiagrass (Paspalum notatum) hay offered free choice and 150 mg monensin x heifer(-1) x d(-1) in addition to either 2.27 kg x heifer(-1) x