Data were collected on 40 Duroc hogs at the University of Tennessee Agricultural Experiment Station, Knoxville, Tennessee to determine the effect of various levels of bird resistant grain sorghum on live perform-ance and carcass characteristics in meat type swine. Rations containing 25, 50, 75, or 100 percent grain sorghum in the grain portion of the ration, were compared with a control ration consisting of 100 percent corn. The protein level (16 percent) remained constant throughout the experiment. There were no significant differences between any of the rations for average daily gains (ADG) during the periods from 40 to 90 pounds, 90 to 140 pounds, 140 to 190 pounds, or 40 pounds to market weight. How-ever, the highest ADG resulted when pigs were fed the 100 percent corn or 25 percent grain sorghum rations. In the periods from 40 to 140 pounds, all of the rations appeared to be equal in producing gain. In a comparison of feed conversion from 40 pounds to market weight between the control ration and rations containing 50, 75, and 100 percent grain sorghum, there was a significant difference (P \u3c ,05) in favor of the control. There was also a significant (P \u3c .01) linear relationship between the percentage of grain sorghum in the ration and the amount of feed required per pound of gain. As the percentage of grain sorghum in the ration increased, the amount of feed required per pound of gain also increased. The increased amount of feed required per pound of gain for the pigs fed the grain sorghum rations ranged from 3 to 8 percent above that amount required by pigs fed the control ration. decreased digestibility of the grain sorghum rations is possibly responsible for the poor feed conversion of the animals fed these rations as shown by the feeding trials