Selection in the host structures the microbiota associated with developing cod larvae (Gadus morhua).
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.
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.
Ingrid
I
Bakke
Department of Cancer Research and Molecular Medicine, Faculty of Medicine, NTNU Norwegian University of Science and Technology, Trondheim, Norway.
Eivind
E
Coward
Department of Bioscience, University of Oslo, Box 1066 Blindern, Oslo, 0316, Norway.
Tom
T
Andersen
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.
Olav
O
Vadstein
D039903:Actinobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D000818:Animals; D041963:Bacteroidetes / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D004269:DNA, Bacterial / Q000235:genetics; D005399:Fishes; D048389:Gadus morhua / Q000196:embryology* / Q000382:microbiology*; D000069196:Gastrointestinal Microbiome / Q000235:genetics*; D041981:Gastrointestinal Tract / Q000382:microbiology*; D007814:Larva / Q000382:microbiology*; D020560:Proteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S