Location: Livestock Nutrient Management ResearchTitle: Effects of twenty percent corn wet distillers grains plus solubles in steam-flaked and dry-rolled corn-based finishing diets on heifer performance, carcass characteristics, and manure characteristics Author
Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/19/2012
Publication Date: 12/15/2012
Citation: Buttrey, E.K., Cole, N.A., Jenkins, K.H., McCollum, F.T., Sakirkin, S.L., Auvermann, B.W., Heflin, K.R., MacDonald, J.C. 2012. Effects of twenty percent corn wet distillers grains plus solubles in steam-flaked-and dry-rolled corn-based finishing diets on heifer performance, carcass characteristics, and manure characteristics. Journal of Animal Science. 90:5086-5098. Interpretive Summary: Including distillers grains in finishing diets may elevate certain nutrient levels beyond what is required by the animal. Nutrients fed in excess of requirements will be excreted in the feces, and urine, which affect the fertilizer value of the manure, thus affecting nutrient management planning, and land area requirements for manure application. Additionally, there is increased interest in the heating value (HV) of livestock manure as an industrial energy source. This study was conducted to determine effects of corn processing method (steam-flaked or dry-rolled), and wet distillers grains plus solubles (WDGS) inclusion (0 or 20% level on a DM basis) on animal performance, carcass characteristics, and manure quality, quantity, and HV. Two hundred sixty-four heifers were placed in the research feedlot, and fed an average of 154 days. Heifers fed diets containing steam-flaked corn consumed less feed, and gained weight more efficiently than heifers fed diets containing dry-rolled corn. When fed diets containing 20% WDGS, heifers were heavier, and more efficient at the end of the feeding period than when diets containing 0% WDGS were fed. Nutrients excreted in the manure were affected by dietary treatment as were nitrogen volatilization losses. These results indicate that corn processing method, and WDGS inclusion can affect cattle performance, and manure management strategies. Each factor appears to be important in consideration of both the amount of manure, and concentration of nutrients in a nutrient management plan.
Technical Abstract: Two hundred sixty-four crossbred heifers (initial body weight = 354 kg +/- 0.5) were used to determine effects of corn processing method and wet distillers grains plus solubles (WDGS) inclusion in finishing diets on animal performance, carcass characteristics, and manure characteristics. The study was conducted as a randomized complete block with a 2 × 2 factorial arrangement of treatments. Dietary treatments included steam-flaked corn (SFC)- and dry-rolled corn (DRC)- based finishing diets containing 0 or 20% WDGS (0SFC and 20SFC, 0DRC and 20DRC, respectively). Heifers averaged 154 days on feed and were marketed in 3 blocks when average fat thickness was estimated to be 1.27 cm. There were no interactions between corn processing method and WDGS detected (P = 0.29) for any performance or carcass response variables. Heifers fed diets containing WDGS tended to have greater final body weight (P = 0.10) and increased Gain:Feed (P = 0.08) compared to heifers fed diets without WDGS. Heifers fed SFC-based diets consumed 7% less feed (P < 0.01) and were 9% more efficient (P < 0.01) than heifers fed DRC-based diets. Carcass characteristics were not affected by corn processing method or WDGS inclusion (P = 0.16). Intakes of organic matter, nitrogen, phosphorus, and potassium were greater (P = 0.05) for heifers fed DRC-based diets than those fed SFC-based diets, which resulted in greater amounts of the nutrients being captured in the manure (P = 0.04). Heifers fed diets containing WDGS had greater (P < 0.01) intakes of nitrogen, phosphorus, and potassium than heifers fed diets without WDGS. As a result, greater amounts of phosphorus and potassium (P = 0.03) and nitrogen (P = 0.10) were captured in the manure from cattle fed diets containing WDGS compared with those fed diets without WDGS. There was no interaction (P = 0.16) between corn processing and WDGS on N volatilization losses. Nitrogen volatilization losses from manure were greater (P < 0.01) for heifers fed SFC-based diets than heifers fed DRC-based diets. Feeding DRC-based finishing diets to heifers resulted in increased manure production and nutrient excretion and decreased N volatilization. Corn processing method and WDGS inclusion both impact animal performance and have nutrient management considerations.