Effect of Dietary Lipid Levels on Fatty Acids Composition of Cultured Sparusaurata

Abstract

Abstract:The aim of this study was to determine the progressive evolution of fish muscle fatty acids composition feeding by different lipid levels of farmed Mediterranean gilthead sea bream (Sparusaurata). During twenty one weeks, Sparusaurata were hand-feed two diets with protein and lipid ratios 47/20 (Diet A) and 45/22 (Diet B) respectively. At the end of the feeding period, lipid contents of muscle, as well as fatty acids profiles of different portions of the muscles were studied. Results indicated the effects of fatty acids profiles of diets throughout the liver and white muscle fillet (dorsal, middle and ventral). These were more noticeable when Sparusaurata was fed on the diet Athat decreased the content of monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA) in all the muscles during the period of feeding while the saturated fatty acids (SFA) content tended to increase and it was lower than ones in the muscles of Sparusaurata fed on diet B. The highest amount of PUFA and docosahexaenoic acid, (22: 6n-3 DHA) were found among the different portions of ventral muscles. In addition, the progressive evolution of different parts of muscle's fatty acid profiles showed significant differences in contents of SFA, PUFA and especially the n-3 PUFA. However, the content of MUFA seems to be alike in different muscles and tended to decrease in dorsal and ventral muscle from D 0 to D f and inversely when the fish were fed on diet A.