Effects of COS on inflammatory cytokines in the spleen. Values presented as mean ± standard error, n = 10. a,b Different superscript letters mean significant differences (p < 0.05). CON, basal diet with normal drinking water; AS, basal diet with 0.1% H2O2 in drinking water; ASC, basal diet supplemented with 200 mg/kg COS, and with 0.1% H2O2 in drinking water. IL-1β, interleukin-1β; IL-6, interleukin-6; IL-10, interleukin-10; TNF-α, tumor necrosis factor-α. (A) the concentration of IL-1β; (B) the concentration of IL-6; (C) the concentration of IL-10; (D) the concentration of TNF-α.