|DROUILLARD, JIM - KANSAS STATE UNIVERSITY|
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/28/2010
Publication Date: 6/1/2010
Citation: May, M.L., Quinn, M.J., Depenbusch, B.E., Reinhardt, C.D., Gibson, M.L., Karges, K.K., Cole, N.A., Drouillard, J.S. 2010. Dried distiller's grains with solubles with reduced corn silage levels in beef finishing diets. Journal of Animal Science. 88:2456-2463.
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. Therefore, we conducted two beef cattle finishing trials to evaluate the use of dried corn distiller’s grains with solubles (DDG) in beef cattle finishing diets. In Trial 1, 377 crossbred heifers (average weight 378 kg) were fed diets consisting of:1) SFC with 0% DDG and 15% corn silage (CS); 2) 25% DDG and 15% CS, or 3) 25% DDG and 5% CS. Heifers fed the 0% DDG diet had lower dry matter intake (9.01 vs. 8.52 kg) than heifers fed 25% DDG and 5% CS. Inclusion of 25% DDG with 15% CS reduced ribeye area compared with 0% DDG and 15% CS (P < 0.05). In Trial 2, 582 crossbreed heifers (average weigh 377 kg) were fed diets similar to Trial 1, but these diets used SFC or dry-rolled corn (DRC) as the basal grain. Treatments contained 1 & 2) DRC or SFC with no DDG and 15% CS, 3 & 4) DRC or SFC with 25% DDG and 15% CS, and 5 & 6) DRC or SFC with 25% DDG and 5% CS. Feeding SFC improved gain:feed ratio (P < 0.05) compared with DRC. Regardless of grain source, feeding 5% CS led to lower dry matter intake and greater gain:feed ratio than feeding 15% CS (P < 0.05). Results suggest that roughage levels can be reduced in feedlot diets containing DDG with no adverse effects on animal performance or carcass quality.
Technical Abstract: Two finishing experiments were conducted to evaluate the use of 25% dried corn distiller's grains with solubles (DDG) in beef cattle finishing diets by partially replacing a portion of the grain and soybean meal in the control diets. In Exp.1, crossbred heifers (n = 377; BW 378 +/- 4.1 kg) were fed diets consisting of steam-flaked corn (SFC) with a control diet containing 0% DDG and 15% corn silage (CS), 25% DDG and 15% CS, or 25% DDG and 5% CS. Compared with the control treatment, heifers fed DDG and 15% CS had a greater proportion of USDA yield grade 4 and 5 carcasses (P = 0.04; 5.68 vs. 14.12), and smaller LM area (P = 0.04; 86.09 vs. 82.48 cm2). In Exp. 2, crossbred heifers (n = 582; BW = 377 ± 27.09 kg) were fed diets similar to Exp. 1 except dry-rolled corn (DRC) and SFC were compared as the basal grain sources. Treatments included DRC or SFC: with control diets containing 0% DDG and 15% CS, 25% DDG and 15% CS, or 25% DDG and 5% CS. Feeding SFC decreased DMI (P < 0.01), improved G:F (P < 0.01) and final shrunk BW (P = 0.05) compared with DRC. Average USDA yield grade was greater for cattle fed DRC than for those fed SFC (P = 0.02), but calculated yield grade was not different among treatments (P = 0.71). Feeding DDG and 5% CS, regardless of grain source, led to decreased DMI and greater G:F than feeding DDG and 15% CS (P = 0.02). When comparing the control treatments with the diets containing 25% DDG and 15% CS shrunk final BW, ADG, and G:F were decreased (P 0.05); however, carcass-adjusted measurements were not different (P > 0.52). Results indicate that roughage levels can be reduced in feedlot diets containing 25% DDG with no adverse effects on BW gain, feed efficiency, or carcass quality.