Bakke Ingrid, Coward Eivind, Andersen Tom, Vadstein Olav
Department of Biotechnology, Faculty of Natural Sciences and Technology, NTNU Norwegian University of Science and Technology, Sem Saelands v. 6/8, N-7491, Trondheim, Norway.
NTNU Centre of Fisheries and Aquaculture, NTNU Norwegian University of Science and Technology, Trondheim, Norway.
Environ Microbiol. 2015 Oct;17(10):3914-24. doi: 10.1111/1462-2920.12888. Epub 2015 Jul 7.
Marine fish larvae are immature upon hatching, and share their environment with high numbers of bacteria. The microbial communities associated with developing fish larvae might be structured by other factors than those important in developing terrestrial animals. Here, we analysed the beta (β)-diversity of the microbiota associated with developing cod larvae and compared it with the bacterial communities in water and live feed by applying pyrosequencing of bar coded v4 16S rDNA amplicons. A total of 15 phyla were observed in the cod larval microbiota. Proteobacteria was the most abundant, followed by Firmicutes, Bacteroidetes and Actinobacteria. The composition and diversity of the cod larval microbiota changed considerably with age. The temporal and spatial patterns of β-diversity could not be explained by stochastic processes, and did not coincide with changes in the rearing conditions. Furthermore, the larval microbiota was highly distinct from the water and the live feed microbiota, particularly at early developmental stages. However, the similarity between larval and water microbiota increased with age. This study suggests that strong selection in the host structures the cod larval microbiota. The changes in community structure observed with increasing age can be explained by altered selection pressure due to development of the intestinal system.
海鱼幼体在孵化时发育不成熟，且与大量细菌共享其生存环境。与发育中的鱼类幼体相关的微生物群落可能由一些与发育中的陆生动物不同的因素所构建。在此，我们通过对条形码标记的v4 16S rDNA扩增子进行焦磷酸测序，分析了与发育中的鳕鱼幼体相关的微生物群的β多样性，并将其与水中和活体饲料中的细菌群落进行了比较。在鳕鱼幼体微生物群中总共观察到15个门。变形菌门最为丰富，其次是厚壁菌门、拟杆菌门和放线菌门。鳕鱼幼体微生物群的组成和多样性随年龄变化显著。β多样性的时空模式无法用随机过程来解释，并且与养殖条件的变化不一致。此外，幼体微生物群与水和活体饲料微生物群截然不同，尤其是在发育早期阶段。然而，幼体与水微生物群之间的相似性随年龄增加。这项研究表明，宿主中的强烈选择塑造了鳕鱼幼体微生物群。随着年龄增长观察到的群落结构变化可以通过肠道系统发育导致的选择压力改变来解释。
