ARS | Publication request: Optimizing use of distiller's grains in finishing diets containing stem-flaked corn

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 1, 2009
Publication Date: N/A

Interpretive Summary: Distiller¿s grains, a by-product of the ethanol industry, are a potentially valuable feed resource for finishing beef cattle. However, little research is currently available to understand optimum methods to feed distiller¿s grains in finishing diets based on steam-flaked corn (SFC). Because distiller¿s grain are high in fiber, it may be feasible to decrease the quantity of roughage in finishing diets that contain distiller¿s grains. In addition, the comparative feeding value of wet (WDGS) and dried (DDGS) distillers grain and between corn-based and sorghum-based DGS in finishing diets is not clear. Therefore, we conducted a beef cattle finishing study to evaluate the effects of DG source and form, and roughage level on beef cattel finishing performance. Two hundred ninety-nine crossbred yearling steers (average weight 363 kg: 49 pens) were fed for an average of 114 d in a finishing study comparing seven diets in which steam-flaked corn was the principal energy source. A control diet with no DGS was compared to 6 diets containing 15% DGS (DM basis). The diets contained wet sorghum DGS with 0 or 6% alfalfa hay; dried sorghum DGS with 0% or 6% alfalfa hay; wet corn DGS with 6% alfalfa hay, or dried corn DGS with 6% alfalfa hay. Dry matter intake (DMI), average daily gain (ADG), gain:feed ratio (G:F) and carcass characteristics were similar (P = 0.18) for steers fed finishing diets with or without 15% DGS. However, apparent total tract dry matter (DM) and organic matter digestibilities were 2.8% less (P = 0.03) for finishing diets containing 15% DGS (DM basis). Dry matter intake, ADG, G:F, apparent total tract digestibility, and carcass characteristics were similar (P = 0.09) for steers fed finishing diets containing sorghum- or corn-DGS. Dry matter intake, ADG, G:F, apparent total tract digestibility, and carcass characteristics also were similar (P = 0.10) for steers fed finishing diets containing wet or dried DGS. Steers fed sorghum DGS with hay consumed more feed (P < 0.01) and gained more weight (P < 0.01) than steers fed diets without hay, but G:F were not different (P > 0.78). Sorghum DGS diets containing alfalfa hay were 4% less (P = 0.01) digestible than diets containing no hay. Carcasses of steers fed sorghum DGS diets without hay were lighter, leaner and had lower USDA yield grades (P = 0.01) than steers fed sorghum DGS diets containing hay. In conclusion, feeding moderate levels (i.e., 15%, DM basis) of DGS resulted in growth performance and carcass characteristics similar to those of cattle fed no DGS. In addition, sorghum- finish.and corn-based DGS had similar feeding values, and wet (¿31% DM) and dried (¿91% DM) DGS also had similar feeding values. Complete removal of alfalfa hay in diets containing DGS improved diet digestibility but reduced growth performance and carcass finish.

Technical Abstract: Two hundred ninety-nine crossbred yearling steers (363 ± 15 kg initial BW) were fed for an average of 114 d in a finishing study comparing 7 diets in which steam-flaked corn was used as the principal energy source. Forty-nine pens were used in this study with 7 weight blocks, 7 pens per treatment, and 5 to 7 steers per pen. A control diet with no distiller¿s grains with solubles (DGS) was compared to 6 diets containing 15% DGS (DM basis). The diets contained wet sorghum DGS with 0 or 6% alfalfa hay; dried sorghum DGS with 0% or 6% alfalfa hay; wet corn DGS with 6% alfalfa hay, or dried corn DGS with 6% alfalfa hay. Apparent total tract digestibilities were calculated by total collection of fecal material from the concrete-surfaced pens over a 72-h period. Dry matter intake, ADG, G:F, and carcass characteristics were similar (P = 0.18) for steers fed finishing diets with or without 15% DGS. However, apparent total tract digestibilities of DM and OM were 2.8% less (P = 0.03) for finishing diets containing 15% DGS (DM basis). Dry matter intake, ADG, G:F, apparent total tract digestibility, and carcass characteristics were similar (P = 0.09) for steers fed finishing diets containing sorghum or corn DGS. Dry matter intake, ADG, G:F, apparent total tract digestibility, and carcass characteristics also were similar (P = 0.10) for steers fed finishing diets containing wet or dried DGS. Steers fed sorghum DGS with hay consumed more feed (P < 0.01) and gained more weight (P < 0.01) than steers fed diets without hay, but G:F were not different (P > 0.78). Sorghum DGS diets containing alfalfa hay were 4% less (P = 0.01) digestible than diets containing no hay. Carcasses of steers fed sorghum DGS diets without hay were lighter, leaner and had lower USDA yield grades (P = 0.01) than steers fed sorghum DGS diets containing hay. Feeding moderate levels (i.e., 15%, DM basis) of DGS resulted in growth performance and carcass characteristics similar to those of cattle fed no DGS. In addition, sorghum- and corn-based DGS had similar feeding values, and wet (¿31% DM) and dried (¿91% DM) DGS also had similar feeding values. Complete removal of alfalfa hay in diets containing DGS improved diet digestibility but reduced growth performance and carcass finish.