Dietary fishmeal levels affect anti-oxidative ability and metabolomics profile of juvenile Pacific white shrimp, Litopenaeus vannamei

In this manuscript, three iso-nitrogenous and iso-lipidic diets containing 50, 150 and 250 g/kg of fishmeal (FM) were fed white shrimp Litopenaeus vannamei for 8 weeks. At the end of feeding, survival and percentage weight gain of shrimp were examined. Hepatopancreas and haemolymph were sampled, activities of superoxide dismutase (SOD) and catalase (CAT), nitric oxide (NO), glutathione (GSH) and malondialdehyde (MDA) levels in hepatopancreas, activities of SOD, CAT, acid phosphatase (ACP) and alkaline phosphatase (AKP), and NO, GSH, MDA in haemolymph were examined. Haemolymph was further subjected to GC-MS analysis. Results indicated that no significant differences in survival rate and percentage weight gain were observed among three treatments. SOD activity and GSH levels in hepatopancreas, and CAT activity, AKP activity, GSH and MDA levels in haemolymph were significantly lower in shrimp fed 50 g/kg FM diet. GC-MS analysis of haemolymph indicated that 81 metabolites were significantly altered in the three groups. Furthermore, 8 metabolism pathways were significantly influenced by dietary FM levels. In conclusion, dietary administration of 50 g/kg FM resulted in inhibition of antioxidant ability, and disordered the energy metabolism, one-carbon metabolism and unsaturated fatty acid metabolism in shrimp.