Effects of Dietary Eucommia ulmoides Leaf Extract on Growth, Muscle Composition, Hepatopancreas Histology, Immune Responses and Microcystin-LR Resistance of Juvenile Red Claw Crayfish (Cherax quadricarinatus)

The objective of the present study was to investigate effects different doses dietary Eucommia ulmoides leaf extract (ELE) on juvenile red claw crayfish (Cherax quadricarinatus). A total number 720 (initial body weight 0.24 ± 0.01 g) were randomly assigned six groups and fed diets containing 0 (Diet 1), 0.5 2), 1 3), 2 4), 4 5) 10 6) g dry (dw) ELE kg (dw)?1 for eight weeks challenged with microcystin-LR stress. results indicated that supplementation 1–2 dw diet could significantly improve gain rate (WGR) specific growth (SGR) crayfish. Muscle crude protein contents Diet 2, 3, higher than those control group. Compared group, increase antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GPx), acid phosphatase (ACP), alkaline (AKP), phenoloxidase (PO) activities decrease malondialdehyde (MDA) level Dietary increased relative expression levels SOD, thioredoxin (TRX1), GPx, selenium-dependent (Se-GPx), cytochrome P450 (CYP450), anti-lipopolysaccharide factor (ALF) C-type lysozyme (C-LZM) mRNA compared group during feeding experiment. When subjected MC-LR stress 48 h, Se-GPx, glutathione-s-transferase (GST1), ALF, hemocyanin (HEM), C-LZM in hepatopancreas be improved varying degrees 1. Supplementation survival (SR) under These (1–2 diet) performance, muscle protein, non-specific immune response SR by regulating immune- antioxidant-related genes.