Tapazole in Steer Finishing Rations: Nitrogen Metabolism

Charolais-Hereford steers were fed 80 g of tapazole per ton of corn-soybean meal ration. Plasma and liver samples and feed efficiency were obtained at eight 14-day periods for 112 days. Vital organ weights and carcass data were collected upon termination of the experiment. Tapazole administration resulted in increased ADG, G/F, PUN, rib eye muscle water and conformation score and a decrease in FI, plasma FAN, plasma PBI, bone weight, heart weight, liver weight, GH/g pituitary and quality grade. No significant differences in other carcass parameters were observed. No significant differences were observed in plasma GH, glucose, pituitary weight or protein synthesis in cell-free liver homogenates. The response of most serial parameters measured was dependent upon time on treatment.