Anthraquinone extract from Bail improves growth performance and Toll-Relish signaling-regulated immunity and hyperthermia tolerance in freshwater prawn .

This study was aimed to investigate the facilitation of anthraquinone extract on growth performance, immunity, and antioxidant capacity of the oriental river prawn (), and whether it could ameliorate the hyperthermia stress. A 12-week rearing experiment was conducted with 0, 125, 250, 500, and 1000 mg kg anthraquinone extract from Bail-supplemented diets (AE0, AE125, AE250, AE500, and AE1000), and followed a 48-h thermal stress with 32℃ incubation. Results indicate AE250 and AE500 significantly improved the growth performance and feed utilization, the optimum level was estimated to be 251.22 mg kg based on the regression analysis of special growth ratio (SGR). Meanwhile, AE250 and AE500 improved antioxidant enzyme activity and immune-related protein concentration of iNOS-NO signaling. Under thermal stress, AE250 and AE500 improved the heat tolerance, and Toll-Relish signaling was active to the resistance. These results indicate anthraquinone extract could be used as an effective immunostimulant to improve growth performance, physiological balance and protect organism form environmental hyperthermia stress. This may provide insights for immunostimulant development in aquaculture production.