Effects of predation stress and food ration on perch gut microbiota

Abstract

BackgroundGut microbiota provide functions of importance to influence hosts’ food digestion, metabolism, and protection against pathogens. Factors that affect the composition and functions of gut microbial communities are well studied in humans and other animals; however, we have limited knowledge of how natural food web factors such as stress from predators and food resource rations could affect hosts’ gut microbiota and how it interacts with host sex. In this study, we designed a two-factorial experiment exposing perch (Perca fluviatilis) to a predator (pike, Esox lucius), and different food ratios, to examine the compositional and functional changes of perch gut microbiota based on 16S rRNA amplicon sequencing. We also investigated if those changes are host sex dependent.ResultsWe showed that overall gut microbiota composition among individual perch significantly responded to food ration and predator presence. We found that species richness decreased with predator presence, and we identified 23 taxa from a diverse set of phyla that were over-represented when a predator was present. For example, Fusobacteria increased both at the lowest food ration and at predation stress conditions, suggesting that Fusobacteria are favored by stressful situations for the host. In concordance, both food ration and predation stress seemed to influence the metabolic repertoire of the gut microbiota, such as biosynthesis of other secondary metabolites, metabolism of cofactors, and vitamins. In addition, the identified interaction between food ration and sex emphasizes sex-specific responses to diet quantity in gut microbiota.ConclusionsCollectively, our findings emphasize an alternative state in gut microbiota with responses to changes in natural food webs depending on host sex. The obtained knowledge from this study provided us with an important perspective on gut microbiota in a food web context.Electronic supplementary materialThe online version of this article (10.1186/s40168-018-0400-0) contains supplementary material, which is available to authorized users.

Composition of the microbial communities in the gastrointestinal tract of perch (Perca fluviatilis L. 1758) and cestodes parasitizing the perch digestive tract

“…The prevalence of invasion of Proteocephalus sp. in perch from Chany Lake was 12.7% that correlates with early investigations where it was shown that prevalence of infestation of P. cernuae in perch from Chany Lake was 13.2% (Sous and Rostovsev 2006 (Li et al, 2014;Silva et al, 2011;Ye, Amberg, Chapman, Gaikowski, & Liu, 2014;Baldo, Riera, Tooming-Klunderud, Albà, & Salzburger, 2015;Kashinskaya et al, 2015;Liu et al, 2016;Zha, Eiler, Johansson, & Svanbäck, 2018).…”

“…By comparing data on bacterial diversity in perch gut with microbiota data from other fish, we can conclude that the microbial composition at the phylum level in the perch intestine conforms to the available literature. Thus, the dominant microbiota in the intestine of freshwater fish was represented by Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, Tenericutes and Fusobacteria (Li et al, ; Silva et al, ; Ye, Amberg, Chapman, Gaikowski, & Liu, ; Baldo, Riera, Tooming‐Klunderud, Albà, & Salzburger, ; Kashinskaya et al, ; Liu et al, ; Zha, Eiler, Johansson, & Svanbäck, ). Other metagenomic studies have shown that the microbiota of the perch P. fluviatilis was dominated by the phyla Tenericutes, Proteobacteria, Fusobacteria and Firmicutes.…”

“…Other metagenomic studies have shown that the microbiota of the perch P. fluviatilis was dominated by the phyla Tenericutes, Proteobacteria, Fusobacteria and Firmicutes. At the genus level, microbiota of healthy perch from Sweden was represented by Myroides , Prochlorococcus , Anabaenopsis , Cetobacterium and an unknown Fusobacteriaceae (Zha et al, ).…”

“…Myroides, Prochlorococcus, Anabaenopsis, Cetobacterium and an unknown Fusobacteriaceae (Zha et al, 2018).…”

Cortisol-induced signatures of stress in the fish microbiome

“…Disruption of the microbiome is likely to represent an important mechanism by which stress affects fish health, welfare and performance in aquaculture. There is some evidence that environmental and social stressors disrupt microbial communities associated with the fish gut and skin (Boutin et al 2013; Sylvain et al 2016; Uren Webster et al 2019; Zha et al 2018), however, a potential role of cortisol in mediating these effects is unknown. We hypothesised that stress-induced cortisol production would directly disrupt the fish microbiome.…”