Effects of temperature on growth performance and metabolism of juvenile sea bass (Dicentrarchus labrax)

Abstract

The European sea bass (Dicentrarchus labrax) has become an increasingly important aquaculture species due to the rapid expansion of farming in China and its commercial popularity in Asia. A 60 day growth trial was conducted to investigate the impact of temperature on growth and ingestion performance and metabolism of the European sea bass (Dicentrarchus labrax). Juvenile European sea bass were stocked in triplicate at 3 temperature conditions (10, 15, and 20 °C). The specific growth rate and feeding rate of European sea bass in both 10 and 15 °C were all significantly lower than fish in 20 °C (P < 0.05). The feed conversion rate of European sea bass was 20 °C > 15 °C (P > 0.05), and 20 °C > 10 °C (P < 0.05). We measured the levels of muscle metabolites of European sea bass, using liquid chromatography with tandem mass spectrometry-(LC-MS/MS) and compared the data among groups using principal component analysis and orthogonal partial least-squares discriminant analysis (OPLS-DA). We also conducted Kyoto Encyclopedia of Genes and Genomes (KEGG) metabolic pathway analysis. OPLS-DA clearly discriminated the muscle metabolites of European sea bass under the three temperature conditions. The important differential metabolites mainly included β-Nicotinamide mononucleotide, nicotinic acid adenine dinucleotide, nicotinic acid, UDP-glucose, glycerophosphatidylcholine, (±)-17-hydroxy-4Z, 7Z, 10Z, 13Z, 15E, 19Z-docosahexaenoic acid, (±)-15-hydroxy-5Z, 8Z, 11Z, 13E, 17Z-eicosapentaenoic acid, γ-linolenic acid, l-serine, inositol, L-citrulline, and succinic acid. The KEGG metabolic pathway analysis showed that lipid metabolism, glucose metabolism, the tricarboxylic acid cycle, the urea cycle, and nicotinate and nicotinamide metabolism may closely related to temperature conditions. The findings of this research suggest that the growth and food intake of European sea bass can be promoted and production can be improved at a culture temperature of 20 °C. Our results provide a theoretical basis and technical guidance for formulating temperature control strategies for industrial recirculating aquaculture of European sea bass.