Submitted to: Livestock Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/29/2011
Publication Date: 8/10/2011
Publication URL: http://dx.doi.org/10.1016/j.livsci.2011.06.025
Citation: Weber, T.E., Kerr, B.J. 2011. Effect of dietary distillers dried grains with solubles on indicators of oxidative stress and immune function in growing pigs. Livestock Science [LIVSCI-01614]. p. 1-7. Available: http://www.sciencedirect.com/science/article/pii/S1871141311002514. Interpretive Summary: With increasing global demand for traditional feedstuffs, there is interest in using byproducts from the biofuels industry as dietary ingredients for swine. Distillers dried grains with solubles (DDGS) from corn ethanol production are increasingly used in pig diets, and, for the most part, provide adequate nutrients for growth and acceptable carcass traits. However, DDGS contain high levels of polyunsaturated fatty acids and some yeast products which may affect oxidative status and immune function. In the current study, indicators of oxidative and immune function were determined in pigs fed a relatively high level of DDGS. This experiment demonstrated that DDGS had relatively little effect on systemic markers of oxidadtive status or inflammation, but dietary DDGS increased total serum immunoglobulins. This information is important for scientists at universities, feed companies, and swine production facilities in that it demonstrates that DDGS can potentially impact immune function when fed to pigs.
Technical Abstract: Distillers dried grains with solubles (DDGS) from corn contain relatively large amounts of polyunsaturated fatty acids and some yeast components, which may increase oxidative stress and alter immune function when fed to pigs. Therefore, indicators of oxidative stress and immune status were determined in pigs (n = 24; initial BW 103.8 ± 5.9 kg) fed corn soybean meal-based diets or diets containing 35% DDGS for 38 days. Blood samples were collected for plasma and erythrocyte glutathione, 4-hydroxynonenal (4-HNE) protein adduct, nitrite, oxygen radical absorbance capacity, and thiobarbituric acid reactive substances (TBARS) analyses. Peripheral blood mononuclear cells were isolated, and lysates were analyzed for 4-HNE, superoxide dismutase-1 and glutathione-s-transferase-4. Fresh urine was collected and analyzed for F2-isoprostane and TBARS. Plasma immunoglobulin A (IgA), IgG, and fecal IgA were determined, and on day 39, pigs fed each diet were injected intramuscularly with saline (n = 6 pigs per diet) or E. coli lipopolysaccharide (LPS; n = 6 pigs per diet) and plasma cytokines and metabolites were determined. There were no differences in basal circulating indicators of oxidative stress between dietary treatment groups, but urinary TBARS were increased (p<0.05) in pigs fed DDGS. Plasma concentrations of IgA and IgG were increased (p<0.05) in DDGS-fed pigs. In pigs fed DDGS, body temperatures were greater (p<0.05) at 4 hours post LPS than pigs fed corn-soybean meal diets, but LPS-induced alterations of plasma cytokines or metabolites were not different between dietary treatment groups. In conclusion, feeding DDGS does not alter circulating oxidative stress indicators, but increases urinary TBARS. Also, DDGS enhances humoral immunity and alters certain aspects of the immune response to LPS.