Applying corn condensed distillers solubles to hay windrows before baling: Effects on bale temperature, nutrient composition, and growing steer-calf performance

Three experiments were conducted to evaluate an alternative method of storing and feeding liquid ethanol coproducts while improving hay bale nutrient quality. In Exp. 1 and 2, corn condensed distillers solubles (CCDS) were applied to native grass windrows producing large, round bales. Inclusion levels (percentage of bale weight, DM) equaled 0 or 20% (Exp. 1) and 0, 16, or 32% (Exp. 2). Level did not affect internal temperature or DM, and 20% CCDS bales had increased (P < 0.01) CP and fat compared with 0% CCDS bales (Exp. 1). No effect of level was observed for DM in Exp. 2, and CP and fat linearly increased (P = 0.02). Bales from Exp. 2 were fed in an 84-d growing period (Exp. 3) with individually fed steers (n = 60, initial BW = 288 ± 11.6 kg) using a 2 × 3 factorial arrangement of treatments. Treatment factors included CCDS level (0, 15, or 30% of diet, DM) with or without supplemental metabolizable protein. Gain and ending BW linearly (P ≤ 0.01) improved as CCDS inclusion increased. Feed efficiency improved linearly (P ≤ 0.01) as CCDS increased but was also enhanced by supplemental metabolizable protein. Data suggest 32% CCDS can be applied to windrows with the methods used in this experiment without affecting internal bale heating or moisture retention. Nutrient analyses and cattle response to increasing CCDS validate that within-bale storage occurred and improved nutrient quality of the bale.