256 Evaluation of Replacement of Dietary Corn with Corn Bran Plus Condensed Distillers Solubles on Growth Performance and Carcass Trait Responses in Finishing Beef Steers

Abstract

Abstract This experiment evaluated replacing dietary corn (50:50 blend of dry-rolled and high-moisture) with corn bran plus condensed distillers solubles (CBCDS) on finishing phase growth performance, efficiency of dietary net energy (NE) utilization, comparative NE value, and carcass trait responses in finishing beef steers. This study used 30 pens of 8 steers/pen assigned to one of three treatments in a randomized complete block design (initial BW=401±43.2 kg); pen served as the experimental unit. Treatments included: 1) finishing diet that contained no corn co-product (Control); 2) finishing diet that contained a dry-corn milling bio-refinery product (20% DM basis inclusion) that replaced corn in the diet: CBCDS; 3) finishing diet that contained a wet-corn milling co-product (20% DM basis inclusion) that replaced corn in the diet: wet corn gluten feed (WCGF). For all analyses, an α of 0.05 determined significance and an α of 0.06 to 0.10 was a tendency. No differences were detected (P ≥ 0.58) among treatments for carcass-adjusted final BW (HCW/0.6433), ADG, or G:F. Observed NE for maintenance and gain was not impacted (P ≥ 0.28) by treatment. No appreciable influence for treatment was detected for the ratio of observed to expected dietary NE for maintenance or gain (P ≥ 0.40). Replacement NEm and NEg values (Mcal/45.4 kg) were determined to be 93.5 and 62.3 for CBCDS and 91.5 and 60.5 for WCGF. There was no influence (P ≥ 0.16) of treatment on DP, HCW, REA, RF, USDA Marbling, KPH, EBF, or final BW at 28% EBF. Treatment tended to influence (P = 0.10) YG, where steers fed WCGF had lesser YG than Control; however, CBCDS diet was intermediate, not differing from WCGF or Control. Distribution of USDA Quality and Yield Grade did not differ (P ≥ 0.29) among treatments. Substitution of corn for CBCDS at 20% of dietary DM can occur without detriment to growth performance or carcass traits.