Wet distillers grains plus solubles concentration in steam-flaked-corn-based diets: Effects on feedlot cattle performance, carcass characteristics, nutrient digestibility, and ruminal fermentation characteristics

Authors: LUEBBE, MATT - Texas Agrilife Research; PATTERSON, JODI - Texas Agrilife Research; JENKINS, KARLA - Texas Agrilife Research; BUTTREY, EMALEE - Texas Agrilife Research; DAVIS, TREVOR - Texas Agrilife Research; MCCOLLUM, F. TED - Texas Agrilife Extension; Cole, Noel; MACDONALD, JIM - Texas Agrilife Research

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/23/2011
Publication Date: 12/6/2011
Citation: Luebbe, M.K., Patterson, J.M., Jenkins, K.H., Buttrey, E.K., Davis, T.C., McCollum, F., Cole, N.A., MacDonald, J.C. 2011. Wet distillers grains plus solubles concentration in steam-flaked-corn-based diets: Effects on feedlot cattle performance, carcass characteristics, nutrient digestibility, and ruminal fermentation characteristics. Journal of Animal Science. 90:1589-1602.

Interpretive Summary: Wet distiller's grains plus solubles (WDG), a co-product of the grain ethanol industry, can be used as a feed ingredient for finishing beef cattle. However, WDG are a new feed ingredient in the Southern Great Plains and more information is needed to determine the optimal way to use this ingredient in cattle finishing diets. To that end, we conducted two experiments to determine the effects of increasing the concentrations of WDG in finishing diets (0, 15, 30,45 or 60% of diet dry matter) based on steam-flaked corn (the predominant feed source used in the Southern Plains) on beef cattle performance and diet digestibility. Animals were also fed a control diet based on dry rolled corn - the predominant form of corn used in Northern Great Plains finishing diets. In Experiment 1, steers fed the steam-flaked corn-based diet had greater weight gain and more efficient weight gain than steers fed the dry rolled corn-based diet. The average daily weight gain and the feed efficiency decreased as the concentration of WDG in the diet increased. In Experiment 2, the digestion of organic matter and neutral detergent fiber were not affected by the corn processing method, but starch digestion was greater for cattle fed steam-flaked corn-based diets than those fed dry rolled corn-based diets. Digestibility of organic matter and starch decreased and digestibility of fiber increased with increasing diet WDG concentration. Feeding steam-flaked corn improved steer performance compared with feeding dry rolled corn. The concentration of wet distiller's grains with solubles and the corn processing method influenced nutrient digestibility and ruminal fermentation. The addition of WDG in steam-flaked corn-based diets appears to negatively affect animal performance by diluting the energy density of the diet.

Technical Abstract: Two experiments were conducted to determine the effects of wet distiller's grains plus solubles (WDG; < 15% sorghum grain) concentration in steam-flaked corn- (SFC) based diets on feedlot performance, carcass characteristics, ruminal fermentation, and diet digestibility of feeedlt ocattle. In Experiment 1, 600 crossbred steers (364 +/- 35 kg avg body weight) were used in a randomized complete block design with 8 replications/treatment. Dietary treatments consisted of a dry-rolled corn (DRC) control diet without WDG, a SFC control without WDG, and SFC with 4 WDG concentrations (15, 30, 45, or 60% on a dry matter basis) replacing SFC, cottonseed meal, urea, and yellow grease. Final body weight (BW), average daily gain (ADG), gain:feed intake ratio (G:F), hot carcass weight (HCW), and 12th rib fat depth were greater (P 0.14) for DRC compared with SFC. Ruminal and total tract starch digestibility was greater (P < 0.01) for SFC than DRC. Dry matter and OM intake were not different (P >/= 0.43) among WDG treatments. Ruminal and total tract OM digestibility decreased linearly (P < 0.01) with increasing WDG concentration. Intake, ruminal, and total tract digestibility of NDF increased linearly (P < 0.01) with increasing WDG concentration. Starch intake decreased linearly (P < 0.01) with increasing WDG concentration. Ruminal starch digestibility increased (P = 0.01) with increasing concentration of WDG. Total tract starch digestibility decreased quadratically (P < 0.01) with increasing concentration of WDG. Feeding SFC improved steer performance compared with DRC. The concentration of WDG with solubles and corn processing method influences nutrient digestibility and ruminal fermentation. The addition of WDG in SFC-based diets appears to negatively impact animal performance by diluting the energy density of the diet.