The variation profile of intestinal microbiota in blunt snout bream (Megalobrama amblycephala) during feeding habit transition

Abstract

BackgroundThe blunt snout bream (Megalobrama amblycephala) is one of the most important commercial herbivorous fish in China, and dietary transition is an important event in blunt snout bream development. Gut microbiota has a vital role to host animal. However, little was known about the relationship among feeding habits transition, gut microbiota and digestive enzymes of gut content.ResultsIn this study, 186,328 high-quality reads from nine 16S rRNA libraries were obtained using the Illumina MiSeq PE300 platform. The valid sequences were classified into 388 Operational Taxonomic Units, and a total of 223 genera, belonging to 20 phyla, were identified. The clustering result of gut bacterial communities is consistently related to the clustering result of intestinal content compositions. Proteobacteria and Firmicutes constitute the ‘core’ gut microbiota of blunt snout bream. Cetobacterium and Rhizobium were identified as microbiological markers of gut microbiota at zooplankton-based diet stages and diet transition stages, respectively. Moreover, thirteen potential cellulose-degrading bacteria were detected in our study. The canonical redundancy analysis (RDA) revealed that the feeding habits strongly influenced the gut microbiota and the digestive enzyme activities of gut content, while the result of PICRUSt test suggests that the metabolic capacity of gut microbiota was affected by feeding habit.ConclusionsThis study provided a comprehensive survey of the gut microbiota in blunt snout bream during its dietary transition period for the first time and clearly showed that the gut microbiota was strongly affected by feeding habit. This work allows us to better understand the relationship among gut microbiota, nutrition metabolism and feeding habits in vertebrate. Further, our study provides a reference for future studies investigating the metabolic adaption of herbivorous fish to shift to a vegetarian diet during their life history.Electronic supplementary materialThe online version of this article (10.1186/s12866-018-1246-0) contains supplementary material, which is available to authorized users.

Effect of dietary oil fromCamelina sativaon the growth performance, fillet fatty acid profile and gut microbiome of gilthead Sea bream (Sparus aurata)

“…In regards to metabolic pathways, the predictive functions of gut microbes in the present studies agree with previous findings that they are mainly associated with the metabolism of carbohydrates, amino acids, energy and to a lesser extent lipids ( Liu et al, 2016 ; Dehler, Secombes & Martin, 2017 ; Lyons et al, 2017 ; Wei et al, 2018 ; Yildirimer & Brown, 2018 ). Actinobacteria, such as Corynebacterium and Gordonia ( Fig.…”

“…The predictive function of the gut microbiome of fish has only been investigated in a small handful of studies ( Lyons et al, 2017 ; Wei et al, 2018 ; Yang et al, 2019 ; Piazzon et al, 2019 ; Qiao et al, 2020 ; Piazzon et al, 2020 ) and to our knowledge this is one of the first investigations of gilthead sea bream. The absence of significant effects of diet or gut section indicate that replacing FO with CO did not drastically alter the composition and function of microbes in the gut.…”

Supplemental Information 1: Fish growth data.

“…In regards to metabolic pathways, the predictive functions of gut microbes in the present studies agree with previous findings that they are mainly associated with the metabolism of carbohydrates, amino acids, energy and to a lesser extent lipids (Liu et al, 2016;Dehler, Secombes & Martin, 2017;Lyons et al, 2017;Wei et al, 2018;Yildirimer & Brown, 2018). Actinobacteria, such as Corynebacterium and Gordonia (Fig.…”

Diversity of gut microbiomes in marine fishes is shaped by host‐related factors

“…According to FishBase (http://www.fishbase.org), there are approximately 33,700 fish species on Earth, accounting for over half of the total number of vertebrate species. The fish digestive tract houses many diverse microorganisms, including bacteria, archaea and fungi, which jointly create a complex microbial ecosystem (Wei et al., 2018). It has been reported that the population density of microbiomes in the marine fish gut is within the range of 10 7 –10 8 cells per gram (Izvekova et al., 2007), suggesting that a vast hidden diversity of microbiomes resides in this habitat.…”