Mycoplasma gallisepticum (MG) infection alone or in combination with other pathogens have brought huge economic losses to the poultry industry. The intestinal microbiota plays a critical role in host defence against respiratory infection. To explore the role of intestinal microbiota in MG-induced inflammation-mediated lung injury and secondary Escherichia coli infection, MG infection model and fecal microbiota transplantation model were developed. The results showed that MG infection changed gut microbiota composition along with lung inflammation injury. Fecal microbiota transplantation from chickens infected with MG to antibiotics cocktail treated chickens decreased host defense against Escherichia coli due to impaired intestinal mucosal barrier, downregulated the mRNA expression levels of host defense enzymes and blocked autophagic flux. Lactobacillus salivarius intake alleviated lung inflammation injury caused by MG infection and increased host defense against Escherichia coli by improved gut microbiota composition. These results highlighted the role of gut microbiota in MG-infection induced lung inflammation injury and secondary infection that offered a new strategy for preventive intervention against MG infection.

单独或与其他病原体结合使用的鸡支原体支原体（MG）感染给家禽业带来了巨大的经济损失。肠道菌群在宿主防御呼吸道感染中起着至关重要的作用。为了探索肠道菌群在MG诱导的炎症介导的肺损伤和继发性大肠杆菌感染中的作用，建立了MG感染模型和粪便菌群移植模型。结果表明，MG感染改变了肠道菌群的组成以及肺部炎症损伤。从感染了MG的鸡到抗生素鸡尾酒处理过的鸡的粪便微生物群移植降低了宿主对大肠杆菌的防御能力由于肠粘膜屏障受损，下调了宿主防御酶的mRNA表达水平，并阻止了自噬通量。唾液乳杆菌的摄入减轻了MG感染引起的肺部炎症损伤，并通过改善肠道菌群组成增强了宿主对大肠杆菌的防御能力。这些结果突出了肠道菌群在MG感染引起的肺部炎症损伤和继发感染中的作用，为预防MG感染的干预提供了新的策略。