Effects of taurine or sodium diformate supplementation to a low fishmeal plant‐based diet fed to European sea bass ( Dicentrarchus labrax )

Abstract

The effects of either taurine (T) or sodium diformate (NDF) supplementation to a low fishmeal (FM) plant-based diet on growth, health status, immunity and muscle cellularity of European sea bass, Dicentrarchus labrax, were investigated. Four isoproteic (44% CP) and isolipidic (17% L) diets were produced to contain 46% FM as a control diet, or 20% FM and a mixture of plant nutrients (PMX). The plant-mix diets were either supplemented or not with 1% T or 0.3% NDF. Each diet was fed to triplicate groups of seabass (mean, 13.71 g) for 13 weeks. Fish fed the PMX diet supplemented with T or NDF was recorded to have a significantly higher feed intake, weight gain and a better feed conversion rate than other groups. The diet composition did not significantly alter the biochemical or essential amino acid composition of fish, except for the slightly reduced lipid content of T-fed fish in comparison to the PMX-fed fish. These supplements further enhanced blood profile, immunity response and myocytes ultrastructure relative to fish fed the PMX diet. Accordingly, these results suggest that supplementation of low-FM/plant-mix diet with either 1% T or 0.3% NDF can promote growth, normalize physiological conditions and improve the striated muscle structure of juvenile seabass.