Dietary calcium pyruvate could improve growth performance and reduce excessive lipid deposition in juvenile golden pompano (Trachinotus ovatus) fed a high fat diet

Excessive lipid deposition in farmed fish is a challenge in the aquaculture industry. To study the effect of dietary calcium pyruvate (CaP) on lipid accumulation in fish, we used a high fat diet (HFD) to establish a lipid accumulation model in juvenile golden pompano (Trachinotus ovatus) and supplemented with 0%, 0.25%, 0.50%, 0.75% and 1.0% CaP (diets D0-D4, respectively). After 8-week feeding in floating cages, dietary CaP significantly improved growth performance, which peaked in fish fed diet D3. Supplementation of CaP significantly decreased whole body lipid content in fish fed D2-D4 and hepatosomatic index and liver lipid content in fish fed D3 and D4. Serum and hepatic antioxidant indices, including glutathione, catalase and superoxide dismutase, showed generally increasing trends in fish fed diets with CaP. In addition, increasing dietary CaP increasingly reduced hepatic activities of hexokinase, phosphofructokinase and pyruvate kinase involved in glycolysis, and increased glycogen contents of the liver and muscle. Dietary CaP up-regulated the liver mRNA expression of ppar alpha, cpt1, hsl and fabp1, but down-regulated expression of srebp-1, fas and acc. In conclusion, 0.75% CaP improved growth performance and reduced excessive lipid deposition by affecting fatty acid synthesis and lipolysis in juvenile T. ovatus fed HFD.