Evaluation of Condensed Distillers Solubles and Field Peas for Feedlot Cattle

Three experiments evaluated the effects of condensed distillers solubles (CDS) on performance and metabolism characteristics in finishing diets. In Exp. 1, 250 crossbred steers (355 ± 18 kg of BW) were used in a randomized complete block design study and fed 0, 9, 18, 27, or 36% CDS to replace a portion of urea and a 1:1 ratio of dry-rolled corn (DRC) and high-moisture corn (HMC). Dietary fat increased from 3.7 to 9.4%, comparing 0 to 36% CDS. Intake decreased linearly (P < 0.01) as CDS increased. A quadratic response was observed for ADG (P = 0.01) with maximum gain calculated at 20.8% CDS, with all inclusions increased versus 0% CDS. A quadratic improvement in G:F was observed (P < 0.01) with a calculated maximum at 32.5% CDS, at which steers were 12% more efficient than those fed 0% CDS. Exp. 2 was a 5 × 5 Latin Square designed metabolism study evaluating the effects of feeding wet distillers grains plus solubles (WDGS) and CDS, both separately and in combination. Diets consisted of a DRC and HMC-based control, a 20% WDGS diet, a 27% CDS diet, and two diets with 20% WDGS plus either 8.5% CDS (LoMix) or 17% CDS (HiMix). Treatment had no effect on DM, OM, NDF, or fat digestibility (P > 0.10). Average ruminal pH was lower for steers fed CDS than for those fed WDGS alone (P = 0.04) and steers fed WDGS spent less time below pH 5.6 than steers fed diets with no WDGS (P = 0.02). Ruminal acetate concentration was lowest for 27CDS and HiMix diets (P < 0.09) and acetate to propionate ratio was numerically lowest for 27CDS and HiMix diets. Exp. 3 was a 2 × 4 factorial randomized complete block design study that evaluated effects of 0, 7, 14, and 21% CDS in diets containing 20% modified distillers grains plus solubles (MDGS) or 20% Synergy (a blend of wet corn gluten feed and MDGS) on performance of finishing