Effects of low‐level dietary microalgae supplementation on the distal intestinal microbiome of farmed rainbow trout Oncorhynchus mykiss (Walbaum)

Abstract

This is the peer reviewed version of the following article: Lyons, P. P., Turnbull, J. In this study, high throughput 16S rRNA sequencing was used to investigate the effect of a 171Samples were allowed to settle, and total genomic DNA was extracted and purified using the 192Illumina libraries were prepared following the method described by Caporaso, Lauber, Walters, All fish consumed both diets readily and upon conclusion of the trial, the weighed individuals 273 from the treatment group had a higher mean weight and condition factor than the control group. 274The final mean weight and condition factor (± SE) for the treatment group was 136.6 ± 12.1g 275 and 1.44 ± 0.06 whereas these values for the control group were 116.5 ± 9.3g and 1.33 ± 0.04 276 respectively ( Figure S1). A t-test was performed using the Minitab 15 statistical software to 277 test for significant differences between the performance parameters for both groups, however 278 no such differences were found (p = 0.107). Sequence data and diversity analyses 280After quality filtering of sequences, a total of 18,282,541 sequences remained for analysis, The overall microbial community composition was similar in both the control and treatment 296 populations of fish. The distribution of OTU's at the phylum level of both the control and 297 treatment libraries is illustrated below (Figure 1). The vast majority of reads were assigned to 298 nine separate bacterial phyla, although an overall total of 13 phyla were recorded. Within these 299 phyla, 13 microbial classes dominated (Figure 2 is still yet to be fully characterized. 329Principal coordinate analyses, when visualized based on the thetaYC distance matrix 330 comparing similarities in community structure, showed that samples were broadly 412The Tenericutes were the dominant microbial phylum in the vast majority of samples, followed

Intestinal microbiota in rainbow trout,Oncorhynchus mykiss, fed diets with different levels of fish-based and plant ingredients: A correlative approach with some plasma metabolites

“…Similar prevalence levels were observed in intestinal contents from channel catfish, largemouth bass and bluegill (Larsen, Mohammed, & Arias, ). Although such overwhelming prevalence of Cetobacterium has not been already reported in rainbow trout, the genus appeared common in trout intestine (Etyemez & Balcazar, ; Kim et al., ; Lyons, Turnbull, Dawson, & Crumlish, ; Lyons et al., ). The most prevalent OTU in the present data was close to Cetobacterium somerae, a possible provider of vitamin B 12 for the host (Tsuchiya et al., ; strains previously classified as Bacteroides type A by Sugita, Miyajima, & Deguchi, ).…”

“…Most studies showed that the bacterial communities in the intestine of rainbow trout changed significantly, depending on the diet with or without plant protein sources as partial substitute for fish meal (Desai et al., ; Heikkinen et al., ; Ingerslev, Strube et al., ; Ingerslev, von Gersdorff Jorgensen et al., ; Mansfield et al., ; Merrifield, Dimitroglou, Bradley, Baker, & Davies, ; Navarrete et al., ; Wong et al., ). The replacement of fish oil by plant oils may also influence gut microbiota (Ingerslev, Strube et al., ; Ingerslev, von Gersdorff Jorgensen et al., ; Lyons, Turnbull, Dawson, & Crumlish, ; Navarrete et al., ).…”

Dietary live yeast and increased water temperature influence the gut microbiota of rainbow trout

“…Increased bacterial diversity in the gut has been found in another single‐celled protein study that fed low inclusion of micro‐algae to rainbow trout kept at 14°C (Lyons et al . ). In contrast, another study found no effect of feeding S. cerevisiae on gut bacterial diversity of rainbow trout, although the yeast was inactivated and the fish were reared at 13°C (Huyben et al .…”

“…; Lyons et al . ). More research is needed to determine the nature of Mycoplasma in the fish gut, especially since it represents a high proportion of the microbiota.…”

Applications of microalga Chlorella vulgaris in aquaculture

“…; Lyons et al . ). Besides, microalgae positively stimulate gut health possibly by altering immunological responses of fish intestinal tissues, perhaps through modulating the nutrient absorption and/or resistance to pathogens (Katerina ; Kousoulaki et al .…”