Effects of Dietary Lipid Levels on Growth, Digestive Enzyme Activities, Antioxidant Capacity, and Lipid Metabolism in Turbot (Scophthalmus maximus L.) at Three Different Stages

Three 56-day feeding trials were conducted to evaluate dietary lipid requirements and effects of levels on growth, digestive enzyme activities, antioxidant capacity, metabolism in turbot (Scophthalmus maximus L.) at three growth stages. The initial mean body weight was 9.13 ± 0.17 g, id="M2"> 50.10 0.38 id="M3"> 80.05 0.76 g (small, medium, large turbot), respectively. Five practical diets formulated contain 68.4, 93.9, 120.7, 147.8, 171.2 g/kg (L68.4, L93.9, L120.7, L147.8, L171.2), Results showed that the gain rate specific fed with L171.2 all significantly higher compared L68.4 L93.9 except for L147.8 diet. Activities intestinal trypsin, lipase hepatic catalase, superoxide dismutase, total capacity firstly increased then decreased as lipids increased. Meanwhile, malondialdehyde content but elevation small medium turbot, it group than rest turbot. With increasing lipid, contents whole-body liver serum cholesterol, triglyceride, low-density lipoprotein cholesterol markedly In addition, high-density over L120.7 group. Transcriptional lipolysis-related genes lipin1 lpl upregulated subsequently downregulated fish. a significant increase lipogenesis-related lxr pparγ expressions detected Based rate, level 130.1, 120.1, 107.7 optimal performance cultured phases, Additionally, results indicated high may lead abnormal deposition affect physiological health