Investigations into the effects of antibiotics on the chicken gut microflora and development of gut-associated immune response

在饲料中使用亚治疗性抗生素是商业家禽生产中常见的做法，是预防细菌感染和促进生长和生产性能的一种方式。然而，细菌中抗生素耐药性的发展正在成为动物和人类的共同问题。此外，抗生素治疗通常会导致肠道微生物群的不稳定，并可能对微生物群与宿主之间的相互作用产生不利影响。许多食源性病原体，如沙门氏菌和弯曲杆菌，都与禽肉、禽蛋和其他产品有关。鸡的肠道菌群能够控制食源性病原体。因此，不当使用抗生素不仅会影响动物健康，还会引起食品安全问题。本节目研究肠道菌群和鸡免疫系统之间的相互作用。此外，它试图确定这些影响的潜在细胞和分子机制。具体而言，该提案将：1)研究饲粮抗生素对肠道菌群组成的影响；2)研究微生物群变化对肠道相关免疫系统的细胞和分子变化；3)研究肠道相关免疫系统在微生物群结构成分刺激后的基因表达。该计划有望为了解饲粮抗生素对鸡免疫系统发育影响的分子/细胞机制提供基础知识。此外，该研究将为鉴定微生物群落中存在的细菌的免疫调节特性奠定基础。

Subtherapeutic use of antibiotics in feed is a common practice in commercial poultry production as a way of prevention of bacterial infections and promoting growth and performance. However, the development of antibiotic resistance in bacteria is becoming a common issue in both animals and humans. In addition, antibiotic therapy often results in destabilization of gut microbiota and could adversely affect interactions between microbiota and the host. Many food-borne pathogens such as Salmonella and Campylobacter are associated with poultry meat, eggs and other products. The gut microbiota of chickens is capable of controlling food-borne pathogens. Therefore, inappropriate use of antibiotics not only affects animal health, but also raises food safety concerns. This program investigates interactions between the gut microbiota and the chicken immune system. Furthermore, it seeks to determine the underlying cellular and molecular mechanisms of these effects. More specifically, the proposal will: 1) examine the effects of dietary antibiotics on the composition of gut microbiota; 2) study cellular and molecular changes in the gut-associated immune system exerted by changes in the microbiota; 3) investigate gene expression in the gut-associated immune system following stimulation with structural components of microbiota bacteria. The proposed program is expected to provide fundamental understanding of the molecular/cellular mechanisms of dietary antibiotics effects on development of the chicken immune system. Furthermore, this research will lay the foundation for identification of immunomodulatory attributes of bacteria present in the microbiota community.