Abstract
Feeding experiments were conducted to determine the requirements of early juvenile red sea bream (Pagrus major) for eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA)by feeding Artemia nauplii containing different levels of EPA or DHA for 12 days. Juveniles fed EPA-enriched Artemia had a high survival rate but very poor vitality, while those fed on Artemia enriched with DHA had both a high survival rate and vitality. The vitality of fish was effectively improved by elevation of DHA levels in Artemia. In the DHA-enriched Artemia, the EPA content increased from the initial value together with the appearance of docosapentaenoic acid (DPA), indicating retroconversion from DHA to EPA through DPA in the nauplii. The requirement of early juvenile red sea bream for DHA was estiated to be 0.95-1.62% in Artemia on a dry matter basis when vitality was used as an index, and was satisfied with 2.25% EPA or 0.95% DHA (2.05% n-3 HUFA) on a dry basis when basedon the survival rate.
