Fig. 3

Effect of C. perfringens challenge and dietary EA levels on intestinal barrier-related biomarkers of broilers at d 42. (A) Diamine oxidase activity (DAO, U/L) in serum. (B and C) The activities of inducible nitric oxide synthase (iNOS, U/mgprot) and lysozyme (LZM, U/mgprot) in jejunal mucosa. (D, E and F) Relative mRNA expressions of zonula occludens 1 (ZO-1), occludin and claudin-2 in jejunal mucosa. (G, H and I) The concentration of malondialdehyde (MDA, nmol/mgprot), and the activities of superoxide dismutase (SOD, U/mgprot) and catalase (CAT, U/mgprot) in jejunal mucosa. Unchallenged, birds without C. perfringens infection; challenged, birds with C. perfringens infection. Values are means (n = 6) with their standard errors represented by vertical bars. ^{a, b} Values with unlike letters were significantly different (P < 0.05). *^, **^, *** Significant main effect (P < 0.05, P < 0.01, P < 0.001) of C. perfringens challenge