Lipid and fatty acid composition of ovaries from wild fish and ovaries and eggs from captive fish of white sea bream (Diplodus sargus)

The fatty acid composition of ovaries from wild white sea bream and ovaries and eggs of captive white sea bream were investigated to estimate the fatty acid requirements of this species. The total lipid (TL) content in wild fish ovaries was similar to that found in ovaries and eggs from captive fish. The general pattern of the fatty acid distribution in lipid of ovaries from wild fish and ovaries and eggs from captive fish was similar. In total lipid, no significative differences in total monoenes, n - 6, n - 3 and n - 3 highly unsaturated fatty acids (HUFA) were found. However, the relative percentage of specific fatty acids differed between wild and captive fish. Thus, arachidonic acid (20:4n - 6, AA) percentage was higher in wild ovaries than in ovaries and eggs from captive fish, whereas eicosapentaenoic acid (20:5n - 3, EPA) showed the opposite trend. In consequence, wild fish presented a lower EPA/AA ratio in their ovaries when compared with ovaries and eggs of captive fish. These differences were extended to all lipid classes studied (triacylglycerol (TG), phosphatidylcholine (PC) and phosphatidylethanolamine (PE)). The present study suggests that essential fatty acids, specially EPA and AA of the diet supplied to the captive white sea bream broodstocks, do not seem to be in an appropriate proportion for this species. (C) 2003 Elsevier Science B.V. All rights reserved.