摘要Oral antibody to interleukin-10(anti-IL-10)enhances the intestinal immune defense against Eimeria.The sulfur amino acids methionine and cysteine(M+C)play essential roles in inducing and maintaining protective immune responses during intestinal infections.Hence,increased dietary M+C may support the anti-IL-10-induced intestinal immunity to Eimeria.Broilers(n=640)were arranged in a 2×2×2 factorial design with 2 levels of each of the 3 main factors:dietary standardized ileal digestible(SID)M+C levels(0.6％or 0.8％),dietary anti-IL-10 supplementation(with or without),and coccidiosis chal-lenge(control or challenge).Briefly,the broilers were supplied with either 0.6％or 0.8％SID M+C,each with or without anti-IL-10(300 μg/kg),from d 10 to 21.On d 14,broilers from each diet were gavaged with either PBS or Eimeria.The resulting Eimeria infection induced fecal oocyst shedding and intestinal lesions.Broilers fed 0.8％SID M+C(main effects,P≤0.05)had decreased feed-to-gain ratio,increased duodenum and cecum luminal anti-Eimeria IgA titers,and decreased fecal oocyst counts,when compared to 0.6％SID M+C.The supplementation of anti-IL-10(main effects,P≤0.05)increased cecum luminal total IgA concentration and decreased cecum lesions.Interactions(P≤0.05)were detected for growth performance and cecum luminal IFN-γ.Briefly,the highest body weight gain and feed intake were reached in PBS-gavaged broilers fed 0.8％SID M+C with no anti-IL-10 and in Eimeria-challenged broilers fed 0.8％SID M+C with anti-IL-10.In Eimeria-infected broilers,anti-IL-10 increased intestinal luminal IFN-γ and body weight gain only at 0.8％SID M+C.Collectively,anti-IL-10 increased intestinal luminal IFN-γ levels,decreased cecum lesions and restored growth only when fed with adequate amounts of sulfur amino acids.Our findings underscore the importance of providing sufficient essential nutrients to support the anti-IL-10 induced immunity against coccidiosis.