High taurine supplementation in plant protein-based diets improves growth and organoleptic characteristics of European seabass (Dicentrarchus labrax)

Yannis Kotzamanis,Vassiliki Ilia,Jan Van Eys,Nicholas Romano,Kriton Grigorakis,Theofania Tsironi,Vikas Kumar,Andreas Brezas,Ioannis Vatsos

doi:10.1038/s41598-020-69014-x

Abstract

Plant-based proteins are increasingly being used in aquafeeds, but one of the limitations is taurine deficiency that can be especially detrimental for carnivorous fish. In this study, taurine supplementation in high plant protein diets (low fish meal, 15%) was investigated on the growth performance and fillet organoleptic characteristics of European seabass (Dicentrarchus labrax), juveniles (78 ± 0.4 g). Five diets were formulated to contain 0 (C−), 5 (T5), 10 (T10) or 20 (T20) added taurine (g/kg), while a control diet (C+) included two-fold higher amount of fishmeal (30%) with no taurine supplementation. Seabass fed the T20 or C+ diet showed similar growth, which was significantly higher compared to those in the C-treatment. Histological examination of the muscle, liver and intestine were similar among treatments. No effect on spoilage bacterial growth or production of total volatile basic nitrogen was observed. Taurine supplementation significantly reduced fillet drip loss, while the fillets of European seabass fed the T10 and T20 diets showed significant higher and lower hardness and adhesiveness values, respectively. Moreover, fillet chewiness was also found to be significantly higher in fish fed the T20 diet compared to C+ and C− diets. Overall, it seems that high dietary taurine supplementation acted as a growth promoter and concurrently improved significantly the postharvest quality characteristics of seabass, which may be attributed to its role in maintaining cell membrane integrity and permeability.

Highlights

Fish meal (FM) for many years was the major protein source for use in aquafeeds, due to its dependence on finite wild-fish s tocks[1] this resource is increasingly being replaced with various plant-based sources in aquafeeds, an approach which supports aquaculture sustainability
The aim of the present study was to investigate the effects of incremental taurine supplementation in a high plant—low FM diet, on the growth performance, and post-harvest fillet organoleptic characteristics of European seabass
Fish fed the C+ and T20 diets showed significantly higher values for weight gain (WG) and daily growth index (DGI) compared to the C− and T5 diets, while the opposite trend was detected for the thermal growth coefficient

Summary

Introduction

Fish meal (FM) for many years was the major protein source for use in aquafeeds, due to its dependence on finite wild-fish s tocks[1] this resource is increasingly being replaced with various plant-based sources in aquafeeds, an approach which supports aquaculture sustainability. Relatively low taurine levels of 2 or 3 g/kg significantly improved the growth of European seabass fry (0.8 initial mean body weight) compared to those fed diets with 0 or 1 g/kg taurine s upplementation[15]. In a low FM diet, dietary taurine supplementation of 0.5% significantly improved European seabass juvenile growth (55 g initial mean body weight)[16]. A research area of high interest is considered to be the potential effects of taurine supplementation in plant protein-based diets on the post-harvest quality of fish fillet[17,18]. The aim of the present study was to investigate the effects of incremental taurine supplementation in a high plant—low FM diet, on the growth performance, and post-harvest fillet organoleptic characteristics of European seabass

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Discussion

Conclusion