SPF鸡粪菌移植对肉鸡肠道菌群微生物组和抗药组的影响机制

Irrational use of antibiotics cause high antibiotic resistance problem in the poultry industry which can’t be reduced by simply controlling antibiotic use. Specific pathogen free (SPF) chicken together with the microbial community it carries and contacts compose “SPF chicken microecosystem”, which microbial flora is complete and stable, sensitive to antibiotics, and free of 19 kinds of specific pathogenic microorganism. So the ideal intestinal flora in broiler can be established by SPF chicken fecal microbiota transplantation to chicks newly hatched. The project first focuses on the construction, maintance of healthy, antibiotic sensitive and complete “SPF chicken microecosystem” and inoculation newly hatched chicks by spraying. Then we will detect the dynamic changes of broiler intestinal flora and the regulatory mechanism of intestinal epithelial cells miRNA to flora stability using microbiome methods, the resistant phenotype of broiler intestinal dominant strains by large-scale antibiotics-sensitive monitoring, integrons distribution and the abundance variation of resistance genes by resistome analysis to analyze the spread and enrichment pattern of resistance gene and explore the mechanism of reducing antibiotic resistance in broiler intestinal flora by SPF chicken fecal microbiota transplantation. Our research will provide technical basis for the establishment of “SPF chicken microecosystem” theory and technology system and the “soft landing” of bacterial resistance in broiler industry.

抗生素的不合理使用导致肉鸡业细菌抗药性问题居高不下，单纯控制抗生素使用无法降低。SPF鸡与其携带的微生物群落构成“SPF鸡微生态体”，其净化了19种特定病原微生物、对抗生素敏感，菌群完整稳定，可通过粪菌移植刚出壳的雏鸡，建立肉鸡肠道理想的微生态体菌群。本项目通过构建和维持健康、敏感、完整的“SPF鸡微生态体”，喷雾接种刚出壳的商品雏鸡，利用微生物组学方法检测肉鸡肠道菌群的动态变化及其肠道上皮细胞miRNA对菌群稳定性的调控机制；利用高通量药敏检测仪监测肉鸡肠道优势菌株抗药性表型；结合抗药组学分析肉鸡肠道菌群整合子携带及抗药基因的丰度变化，解析菌群抗性基因的扩散和富集规律，探索SPF鸡粪菌移植降低肉鸡肠道菌群抗药性的影响机制。本项目为“SPF鸡微生态体”粪菌移植理论和技术体系的建立及实现肉鸡业抗药性的“软着陆”提供技术依据。

商品肉鸡肠道菌群中细菌的抗药性水平普遍较高，为了探索一种非抗生素的生态疗法，我们尝试利用SPF鸡的粪便菌群移植接种给新生的雏鸡，以期达到降低细菌抗药性，提高动物抗病能力的目的。首先对普通商品蛋鸡和SPF蛋鸡不同日龄的粪便菌群进行了16S rRNA基因高通量测序分析，获得了粪便菌群的多样性及基本组成结构组成信息，并得到了雏鸡菌群随日龄变化而成熟的动态信息。接着利用成年SPF鸡的盲肠菌群接种新生雏鸡，不同日龄检测了雏鸡肠道菌群的抗药性水平及菌群结构的变化分析。进一步研究了利用SPF鸡的粪菌移植及其噬菌体疗法在抵抗雏鸡早期沙门氏菌感染的作用及机制。本研究为家禽业利用粪菌移植和/或噬菌体疗法降低细菌抗药性及抵抗病原菌的感染提供了新的研究方法和思路。