The effect of live food enrichment with docosahexaenoic acid (22:6n-3) rich emulsions on growth, survival and fatty acid composition of meagre (Argyrosomus regius) larvae

While spawning induction and larval rearing of meagre (Argyrosomus regius) have advanced as forcing factors to move this finfish species into the commercial aquaculture sector, larval nutrition still has unanswered issues to address, specifically in regard to live prey enrichment and fatty acid composition. In this study, two experimental trials for larval rearing of meagre utilizing different methods of live prey enrichment with emulsions of different specialist oils having distinct fatty acid composition, have demonstrated that docosahexaenoic acid (DHA) requirements may be species-specific, with a DHA supplement of 12-15% in live prey enrichment diets yielding optimum larval growth. Cannabilism in early life stages (post 20 dph) in this species also remains a challenge and requires stocks to be managed accordingly. Further, we found evidence suggesting meagre larvae are not capable of elongation or desaturation of fatty acids when precursors such as LA, GLA, LNA or SDA are offered in the live prey.