Biochemical studies on the lipid content of Tilapia nilotica and Sparus auratus.

Seasonal variations of total lipids, free fatty acids, triglycerides, phospholipids and cholesterol content of the freshwater fish Tilapia nilotica and the marine fish Sparus auratus were investigated. Male fish of S. auratus showed higher muscular and hepatic total lipids and hepatic free fatty acids than those of T. nilotica (P less than 0.05). The mean differences in gonadal male lipids of the two species were not significant. Tilapia nilotica female fish showed a significantly higher content of hepatic free fatty acids, phospholipids and cholesterol (P less than 0.01, 0.01, 0.05 respectively) and gonadal total lipids, triglycerides, and cholesterol (P less than 0.05) than those of S. auratus females. In contrast S. auratus females exhibited higher muscular total lipids, triglycerides, phospholipids and cholesterol content (P less than 0.01, 0.05, 0.02, 0.05, respectively) and gonadal phospholipids (P less than 0.05) than those of the T. nilotica females. In general hepatic and gonadal lipids of freshwater fish T. nilotica were higher than those of the marine fish S. auratus, and in contrast the marine fish contained higher muscular lipids than the freshwater fish.