Intestinal microbiota of Atlantic salmon freshwater parr and seawater post-smolts

Atlantic salmon undergo dramatic physiological changes as they migrate from freshwater to the marine environment. Osmoregulatory adaptation is the most crucial change, necessitating functional adaptations of the gills, kidney and intestine. Additionally, novel pathogens, microbes and dietary items are encountered in the saltwater environment, which suggests major changes in the intestinal microbiota following movement to saltwater.This study compared the intestinal microbiota harboured in the distal digesta of Atlantic salmon freshwater fish kept in a commercial Scottish freshwater hatchery with that of their full-siblings after seawater acclimatisation by a 16S rRNA targeted high throughput sequencing approach. The results will help to enhance our understanding of how physiological changes within the host parallel to habitat change can affect the microbial community harboured in the intestine.

大西洋鲑鱼从淡水环境向海洋环境洄游时，会经历剧烈的生理变化。其中渗透调节适应（osmoregulatory adaptation）是最为关键的改变，需要鳃、肾脏与肠道产生相应的功能适应性调整。此外，海水环境中会遭遇全新的病原体、微生物与食物来源，这表明大西洋鲑鱼迁至海水后，其肠道微生物群会发生显著变化。本研究采用16S rRNA靶向高通量测序技术，对比了苏格兰商业化淡水孵化场饲养的淡水养殖大西洋鲑鱼，与其经海水驯化的全同胞个体的肠道远端食糜中定植的肠道微生物群。本研究结果将有助于加深我们对宿主伴随生境改变所发生的生理变化如何影响其肠道内定植的微生物群落的认识。