Oils Combination with Microalgal Products as a Strategy for Increasing the N-3 Long-Chain Polyunsaturated Fatty Acid Content in Fish Oil-Free Diets for Meagre (Argyrosomus regius)

Diversification of species and ingredients is essential for further developing aquaculture production. The present study aimed to evaluate the potential a blend microalgae oils poultry oil as total replacers fish in aquafeeds, fast-growing diversification, that was shown require high dietary n-3 LC-PUFA levels. For purpose, meagre juveniles ( 2.74 ± 0.01 g initial body weight) were fed one four experimental diets 30 days. A control diet (FO diet) based on 5% 7% rapeseed oil, whereas other three diets, totally replaced by either only (PO diet), or blending two commercial algal (ED DD diets). Growth performance, tissue composition, expression genes related fatty acid biosynthesis, antioxidant defense system, heat shock proteins determined. Diets with blends supported good growth feed utilization meagre. Besides, these maintained DHA contents fillet lipid quality indices, like those containing oil. Furthermore, ED showed highest gpx, agreement polyunsaturated content. These results demonstrated completely replace cost-effectevily In contrast, PO sole replacer not able support performance LC-PUFA, leading an increased thrombogenic index fillets. Additionally, low dietay content upregulated relative offads2 while downregulating gpx compared microalgal diets.