规模化蛋鸡场病原菌溯源与生物安全防控研究

细菌病严重威胁蛋鸡健康,以抗生素为主导的细菌病传统防控方式会导致病原菌耐药性严重、鸡蛋药物残留,影响蛋品安全。要保证蛋鸡产蛋期不用抗菌药物而又能生产出"无菌、无抗"的鸡蛋,是国内外技术难题。本团队以规模化蛋鸡场全封闭鸡舍为研究对象,基于PFGE、MLST、全基因组测序等技术,探明了蛋鸡病原菌的种类及基因组特征;对病原菌的耐药性研究表明,蛋鸡病原菌多重耐药严重,依靠药物防控的方式亟待转变;对规模化蛋鸡场细菌溯源研究结果表明,鸡舍生物媒介(鼠、苍蝇等)和非生物媒介(空气、饮水、饲料、鸡粪等)是蛋鸡病原菌的重要传染来源和传播途径;对规模化蛋鸡场生物安全量化评价结果表明,外部和内部生物安全权重高达92.2%。根据溯源和生物安全权重分析结果,提出了在规模化全封闭蛋鸡舍将蛋鸡细菌病从药物防控转变为生物安全防控的新策略;创新了规模化蛋鸡场细菌病防控的系统技术,实现蛋鸡规模养殖整个产蛋期不用抗生素,为生产"无菌、无抗"安全鸡蛋提供技术支撑。

Tracing Sources and Bio-safety Control of Pathogenic Bacteria from Large-scale Layer Farms

Pathogenic bacteria pose a serious threat to the health of laying hens. Traditionally, antimicrobials are used to prevent and control bacterial diseases in laying hens, causing serious antimicrobial resistance and drug residue in eggs, which has a severe impact on egg safety. Bacteria and antimicrobials-free eggs can be produced without antimicrobials in the whole cycle, which had become important demands and technical challenges for safe eggs worldwide. In this paper,we focused on totally enclosed henhouses in large-scale layer farms and revealled the species of pathogenic bacteria and genomic characteristics using PFGE, MLST and whole genome sequencing. Antimicrobial resistance studies showed that pathogenic bacteria from laying hens exhibited multidrug resistance profiles, indicating that it was very urgent to change the control strategy of using antimicrobials. Tracing sources of the pathogenic bacteria showed that the biotic vectors(mouse and fly) and abiotic vectors(air, water, fodder and chicken feces) were the important sources and transmitting vectors of pathogenic bacteria in large-scale layer farms. Quantitative evaluation of bio-safety in large-scale layer farms showed that external and internal bio-safeties made up 92.2% of the overall weight. The results of the tracing and quantitative evaluation of bio-safety supported that antimicrobial control should be switched to bio-safety control.Systematic control technologies for bacterial diseases in laying hens were provided, realizing that no antimicrobial was used in the whole cycle. Thus, bacteria and antimicrobials-free safe eggs were produced.