DETERMINATION OF THE REQUIREMENT OF LARVAL STRIPED JACK FOR EICOSAPENTAENOIC ACID AND DOCOSAHEXAENOIC ACID USING ENRICHED ARTEMIA-NAUPLII

Two experiments were conducted to decide the requirement of larval str iped jack Pseudocaranx dentex for eicosapentaenoic acid (EPA) and doco sahexaenoic acid (DHA) by feeding Artemia nauplii containing different levels of EPA and/or DHA for 11 or 12 days. Fish fed oleic acid (OA) enriched Artemia containing a low amount of n-3 highly unsaturated fat ty acids (n-3HUFA, mainly EPA and DHA) showed low growth and survival rate, and poor vitality (survival rate at activity test). Elevation of DKA levels in the nauplii improved survival, growth, and vitality. Ho wever poor vitality was observed even though fish fed EPA enriched Art emia. Fatty acid compositions of polar lipid in fish body clearly refl ected the composition of nauplii. In healthy fish with strong vitality , the ratio of 18:1/22:6n-3 in body polar lipids remained below 1. Thi s ratio could be an appropriate index for EFA status of larval striped jack. The requirement of-larval striped jack for DHA during the Artem ia feeding period is estimated to be 1.6-2.2% in Artemia (dry basis) b ased on larval vitality. On the other hand, fish fed EPA enriched Arte mia containing more than 3.1% EPA does not improve neither vitality no r survival.