BIOCHEMICAL-COMPOSITION AND FATTY-ACID CONTENT OF FERTILIZED-EGGS, YOLK-SAC STAGE LARVAE AND FIRST-FEEDING LARVAE OF THE SENEGAL SOLE (SOLEA-SENEGALENSIS KAUP)

Changes in biochemical composition and fatty acid content were investi gated during the early development of the Senegal sole (Solea senegale nsis Kaup). The pattern of lipid utilization in this rapidly developin g marine flatfish species favored neutral lipids, particularly triacyl glycerol and sterol ester fractions. Fertilized eggs and yolk sac larv ae were richer in neutral lipids, which decreased during development. In contrast, a significant increase occurred to proportions of phospho lipids, mainly due to significant increases in minor classes such as p hosphatidylserine, phosphatidylinositol and phosphatidic acid/cardioli pin, whereas major phospholipid classes such as phosphatidylcholine an d phosphatidylethanolamine remained constant during development. Satur ated and monounsaturated fatty acids such as 16:0, 16:1 n-7, 18:1 n-9 and 18:1 n-7 were utilized to a greater extent than polyunsaturated fa tty acids as energy substrates. A requirement for long-chain polyunsat urated fatty acids such as eicosapentaenoic acid (20:5n-3) and docosah exaenoic acid (22:6n-3) is likely since no evidence of bioconversion f rom their precursors was found. A requirement for arachidonic acid (20 :4n-6) is also suggested as it is specifically retained throughout dev elopment.