This study evaluates the effects of probiotics and synbiotics on the performance, immune responses, and intestinal morphology, and the expression of immunity-related genes of broiler chicks challenged with Salmonella typhimurium. Three hundred and sixty broiler chicks were divided into six groups, including broiler chicks challenged and non-challenged with S. typhimurium and fed with probiotic, synbiotic, and basal diet without additive. Growth performance (food intake, daily gain, feed conversion ratio, and mortality), immune responses (antibody titer against sheep red blood cells, immunoglobulins G and M), intestinal morphology, lactic acid bacteria population, and the expression of immunity-related genes (interferon-γ, interleukins 6 and 12, and tumor necrosis factor-α) were investigated. The administration of S. typhimurium decreased growth performance (P = 0.0001), immune responses (P = 0.0001), intestinal morphology (P = 0.0001), lactic acid bacteria population (P = 0.0001), and the expression of immunity-related genes (P = 0.0001) of broiler chickens. However, broiler chicks fed with probiotic (P = 0.001) and synbiotic (P = 0.0001) showed better growth performance, immune responses, intestinal morphology, lactic acid bacteria population, and the expression of immunity-related genes in comparison with infected broiler chicks fed with basal diet lack of probiotic and synbiotic. Feeding probiotics (P = 0.001) and synbiotics (P = 0.0001) showed positive effects for challenged and non-challenged broiler chicks. In sum, feeding synbiotic and probiotic alleviated the negative effects of S. typhimurium on growth and immunity of broiler chicks. It can be suggested to apply synbiotic and probiotics as benefit additive against infectious challenges, such as S. typhimurium.

本研究评估了益生菌和合生元对受到鼠 伤寒沙门氏菌攻击的肉鸡的性能、免疫反应和肠道形态以及免疫相关基因表达的影响。三百六十肉鸡被分为六组，其中包括肉鸡挑战，并与未经攻S. 鼠伤寒沙门氏菌并饲喂益生菌、合生元和不含添加剂的基础日粮。生长性能（采食量、日增重、饲料转化率和死亡率）、免疫反应（抗羊红细胞抗体滴度、免疫球蛋白 G 和 M）、肠道形态、乳酸菌种群和免疫相关基因的表达（干扰素-γ、白细胞介素 6 和 12 以及肿瘤坏死因子-α）进行了研究。的给药S. 鼠伤寒降低生长性能（P  = 0.0001），免疫应答（P  = 0.0001），肠形态（P  = 0.0001），乳酸菌群（P  = 0.0001），和免疫相关的基因（表达磷 = 0.0001) 肉鸡。然而， 与饲喂受感染的肉鸡相比，饲喂益生菌 ( P  = 0.001) 和合生元 ( P = 0.0001) 的肉鸡表现出更好的生长性能、免疫反应、肠道形态、乳酸菌种群和免疫相关基因的表达。与基础饮食缺乏益生菌和合生元。饲喂益生菌 ( P  = 0.001) 和合生元 ( P  = 0.0001) 对受攻击和未受攻击的肉鸡均有积极影响。总之，喂养合生元和益生菌缓解的负面影响S. 鼠伤寒对肉鸡生长和免疫的影响。它可以建议采用合生元和益生菌作为对抗传染病的挑战，如受益添加剂S. 鼠伤寒沙门氏菌。