Synbiotic feed supplementation significantly improves lipid utilization and shows discrete effects on disease resistance in rainbow trout (Oncorhynchus mykiss)

Abstract

Enteric redmouth disease caused by the bacterial pathogen Yersinia ruckeri is the main reason for antimicrobial prescription, and a cause of substantial economic losses and decreased animal welfare in aquaculture. Given the importance of the intestinal microbiota in digestion and disease, our aim was to investigate whether synbiotic feed supplementation strategies could improve feed performance and disease resistance. Four experimental synbiotic feeds formulated with pre- and probiotics were tested against a commercially available probiotic control feed. Each experimental feed was evaluated for feed performance, effects on gross as well as intestinal morphometrics, and finally their effect on resistance against a waterborne experimental infection with Yersinia ruckeri serotype O1, biotype 2. While co-supplementing Pediococcus acidilactici with citrus flavonoids or bacterial paraprobiotics significantly improved utilization of feed lipid content relative to the control group, a decrease in lipid utilization was observed for feeds that combined P. acidilactici with yeast paraprobiotics. No significant improvements on disease resistance were observed. Still, synbiotic formulations including P. acidilactici led to reduced risks relative to that of the control group, while an increased relative risk was observed for a Bacillus-based formulation. In conclusion, two of the synbiotic supplements significantly improved lipid utilization and contributed to minor increases in disease resistance.

A Multi Omics Approach Unravels Metagenomic and Metabolic Alterations of a Probiotic and Synbiotic Additive in Rainbow Trout (Oncorhynchus Mykiss)

“…The sourcing of sh and rearing procedures used in this study have previously been described in a separate study 75 . Brie y, we obtained rainbow trout eggs from the AquaSearch FRESH strain (all-female, AquaSearch OVA, Billund, Denmark).…”

“…Furthermore, the speci c fat and protein content for each experimental feed was determined using near-infrared spectroscopy as part of internal quality control at BioMar 76 . Calculations of parameters were calculated according to previous study 75 (Supplementary information 3.3.6).…”

A multi omics approach unravels metagenomic and metabolic alterations of a probiotic in rainbow trout (Oncorhynchus mykiss)

“…The sourcing of sh and rearing procedures used in this study have previously been described in a separate study 70 . Brie y, we obtained rainbow trout eggs from the AquaSearch FRESH strain (all-female, AquaSearch OVA, Billund, Denmark).…”

“…Weight, fork length, and qualitative comments regarding wounds were recorded for each individual. All individuals were euthanised, according to the approved experimental guidelines, using Benzocaine in water prior to dissection, as detailed in a previous study 70 .…”

“…Calculations of parameters were calculated according to previous study 70 (Supplementary information 3.3.6).…”