title: Effects of emodin and vitamin E on the growth and crowding stress of Wuchang bream (Megalobrama amblycephala).
abstract: This study aimed to investigate the effects of dietary emodin, high-dose vitamin E and their combination on the growth of Megalobrama amblycephala and its resistance to acute crowding stress. The fish were randomly divided into four groups: a control group fed with basal diet, and three treatment groups fed with basal diet supplemented with 60 mg/kg emodin (the emodin group), 500 mg/kg vitamin E (the vit E group), and 60 mg/kg emodin together with 500 mg/kg vitamin E (the combination group). After 60 days, the fish were exposed to acute crowding stress for 24 h. The results showed that the weight gain of the vit E group, specific growth rate of the vit E group, total serum protein concentration (TP) of the vit E group, serum lysozyme activity of the emodin group, serum superoxide dismutase (SOD) activity of the emodin group, hepatic heat shock protein 70 (HSP70) levels of the vit E group and the emodin group, and serum alanine aminotransferase (ALT) activity of the combination group significantly increased while the weight gain and specific growth rate of the combination group significantly decreased compared with the control group before stress. After crowding stress, the vit E group had improved serum TP 12 h post-stress, hepatic SOD activity 24 h post-stress, and hepatic HSP70 mRNA levels 12 and 24 h post-stress while the emodin group had enhanced serum SOD activity 12 and 24 h post-stress and hepatic HSP70 mRNA levels 12 and 24 h post-stress, as compared with the control. However, the serum cortisol content of the three treatment groups 12 and 24 h post-stress, ALT activity in the vit E group and emodin group 24 h post-stress, and serum alkaline phosphatase and liver catalase activity in the combination group 24 h post-stress were lower than those in the control group. The cumulative mortality was lower in the emodin, vit E, and combination group after Aeromonas hydrophila infection compared with the control group. Therefore, dietary supplementation with 60 mg/kg emodin or 500 mg/kg vitamin E can improve HSP70 mRNA levels and antioxidant capabilities, resistance to crowding stress, and growth in M. amblycephala. However, the combination of emodin and vit E does not have a synergistic effect in M. amblycephala.
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; Wuxi Fishery College, Nanjing Agriculture University, Wuxi 214081, China. Electronic address: liub@ffrc.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; Wuxi Fishery College, Nanjing Agriculture University, Wuxi 214081, China.
authors.forename: Pao
authors.initials: P
authors.lastname: Xu
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; Wuxi Fishery College, Nanjing Agriculture University, Wuxi 214081, China. Electronic address: Xiej@ffrc.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Xie
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China; Wuxi Fishery College, Nanjing Agriculture University, Wuxi 214081, China. Electronic address: gexp@ffrc.cn.
authors.forename: Xianping
authors.initials: X
authors.lastname: Ge
authors.affiliation: Wuxi Fishery College, Nanjing Agriculture University, Wuxi 214081, China.
authors.forename: Silei
authors.initials: S
authors.lastname: Xia
authors.affiliation: Wuxi Fishery College, Nanjing Agriculture University, Wuxi 214081, China.
authors.forename: Changyou
authors.initials: C
authors.lastname: Song
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
authors.forename: Qunlan
authors.initials: Q
authors.lastname: Zhou
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
authors.forename: Linghong
authors.initials: L
authors.lastname: Miao
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
authors.forename: Mingchun
authors.initials: M
authors.lastname: Ren
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
authors.forename: Liangkun
authors.initials: L
authors.lastname: Pan
authors.affiliation: Key Open Laboratory for Genetic Breeding of Aquatic Animals and Aquaculture Biology, Ministry of Agriculture, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China.
authors.forename: Ruli
authors.initials: R
authors.lastname: Chen
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D016980:Aeromonas hydrophila / Q000502:physiology; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001774:Blood Chemical Analysis / Q000662:veterinary; D003530:Cyprinidae / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis; D004642:Emodin / Q000008:administration & dosage / Q000494:pharmacology*; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics* / Q000378:metabolism; D007113:Immunity, Innate / Q000187:drug effects; D008099:Liver / Q000187:drug effects / Q000276:immunology; D010084:Oxidation-Reduction; D013312:Stress, Physiological / Q000187:drug effects*; D014810:Vitamin E / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D000276:Adjuvants, Immunologic; D029941:Fish Proteins; D018840:HSP70 Heat-Shock Proteins; D014810:Vitamin E; D004642:Emodin
keywords: Crowding stress; Emodin; Growth; Megalobrama amblycephala; Vitamin E