Thirty-six half-sibling Angus bulls were assigned one of three diets: 1) 60% corn-based (CON; S = 0.18%; n = 12); 2) 60% DDGS replacing corn (60DDGS; S = 0.55% DM; n = 12); 3) CON diet + equivalent sulfur of 60DDGS added as calcium sulfate (SULF; S = 0.54%; n = 12) to evaluate the effects of feeding diets containing DDGS or calcium sulfate on performance and semen characteristics. Bulls began the study at 9 months of age and gained 1.6 kg/day for 112 days. Treatment by day interactions (P < 0.05) were observed for glutathione peroxidase and trace mineral concentrations in seminal plasma. Effects of treatment (P < 0.05) were observed for semen kinematics and triiodothyronine in serum. Alterations observed when feeding 60% DDGS to developing bulls occurred in a manner that is not dependent on dietary sulfur; therefore, observed changes could be related to other components within DDGS.