Effect of Seasonal Change and Different Commercial Feeds on Proximate Composition of Sea Bream (Sparus aurata)

The fillet lipid content, lipid deposition in liver, total lipid level in visceral organs (without liver), the hepatosomatic index and viscerosomatic index of the fish fed the extruded feeds were significantly higher (P<0.05) than the fish fed the pelleted feeds. The hepatosomatic index and viscerosomatic index and the lipid accumulation in the fillet and the liver of the cultured fish were significantly higher (P<0.05) than the wild fish in the same area. There was a positive correlation between the seasonal seawater temperature and the lipid deposition in the fillet (r = 0.62, P<0.05) and visceral organs (r = 0.87, P<0.01) of the wild and cultured fish. There was a higher negative correlation (r = - 0.83, P<0.01) between the water temperature and the lipid deposition in the liver of cultured fish. There was no significant difference (P>0.05) between the crude protein levels in the fillet of the cultured and wild sea bream in summer. There were significant differences (P<0.05) in the fillet of cultured fish groups. Finally, the proximate compositions in the commercial feeds used in the sea farms of the Aegean region were found sufficient for sea bream. Furthermore, the higher fat level in the extruded feeds did not show negative effects on the proximate composition of the fish fillet. Keywords : Sea bream, Sparus aurata, commercial feeds, nutrition, body composition, seasonal effects