1. A 23 factorial with a split-plot allocation of treatments was used to investigate the effects of silage type, (sweet v. grain sorghum); level of urea, (60ν. 120 g. per head per day); vitamin A,(0ν. 40,000 i.u. per head per day), and intraruminal cobalt oxide pellet on the performance of steers fed rations of 90% sorghum grain, 10% sorghum silage.