Effect of dietary phospholipid levels on growth, lipid metabolism, and antioxidative status of juvenile hybrid snakehead (Channa argus×Channa maculata).

The study was conducted to evaluate the effect of dietary phospholipids (PLs) on growth, lipid metabolism, and antioxidative status of hybrid snakehead (Channa argus × Channa maculata). Five isonitrogenous and isolipidic diets with graded levels of PLs (8.5, 19.3, 30.7, 41.5, and 50.8 g kg-1) were fed to triplicate groups of juveniles (initial body weight 12.6 ± 0.23 g) for 8 weeks. Results showed that dietary PL supplementation significantly improved growth of juveniles. The final body weight (FBW) and specific growth rate (SGR) significantly increased with dietary PLs increasing from 8.5 to 41.5 g kg-1 (P < 0.05). Fish fed with the diet containing 8.5 g kg-1 PLs showed higher feed conversion ratio (FCR) compared to the other treatments (P < 0.05). Survival rate (SR) was not affected by dietary PL levels (P > 0.05). Liver lipid contents, serum triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) contents significantly decreased with the increasing levels of dietary PLs (P < 0.05). However, serum total cholesterol (TC) and high-density lipoprotein cholesterol (HDL-C) contents and HDL-C/TC and HDL-C/LDL-C value significantly increased with increasing dietary PL levels (P < 0.05). The catalase (CAT), superoxide dismutase (SOD), and carnitine palmitoyl transferase I (CPT-1) activities in the liver significantly increased with incremental dietary PL level (P < 0.05), while the liver malondialdehyde (MDA) contents and fatty acid synthase (FAS) activity significantly reduced (P < 0.05). No significant difference was observed in the glutathione peroxidase (GPx) activity among dietary treatments (P > 0.05).These results confirmed that dietary PL supplementation has beneficial effects on growth performance and antioxidant capacity of juvenile hybrid snakehead. Dietary PLs might reduce lipid deposition in the liver of juvenile hybrid snakehead.