Abstract The aim of the present study was to assess the effects of dietary oak (Quercus castaneifolia) leaf extract supplementation on growth performance, antioxidant, immune and stress responses in common carp (Cyprinus carpio). Ethanolic extract of the oak leaf were prepared and tested for in vitro radical scavenging and antibacterial properties. The results showed that the extract has radical scavenging property below that of butylated hydroxytoluene (BHT) at 12.5–75 μg mL−1, but there was no significant difference between the two materials at 100 and 200 μg mL−1. Moreover, the extract had bactericidal effects against Aeromonas hydrophila, which was near 5-fold lower than tetracycline. Then, the extract was added to the fish diet at 0 (CTL), 0.5 (0.5E), 1 (1E) and 2 (2E) g kg−1 diet. The fish were fed with aforementioned diets for 60 days before subjecting to a 6-h crowding stress. The results showed that the extract had no significant effects on the fish growth performance (P > .05). Dietary extract supplementation (1E and 2E) significantly increased plasma superoxide dismutase (P = .003), catalase (P = .015), glutathione peroxidase (P

中文翻译：

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日粮橡木（Quercus castaneifolia）叶提取物对鲤鱼（Cyprinus carpio）生长、抗氧化和免疫特性及拥挤应激反应的影响

摘要 本研究的目的是评估添加橡木 (Quercus castaneifolia) 叶提取物对鲤鱼 (Cyprinus carpio) 生长性能、抗氧化、免疫和应激反应的影响。制备橡树叶的乙醇提取物并测试其体外自由基清除和抗菌特性。结果表明，该提取物在 12.5-75 μg mL-1 时具有低于丁基化羟基甲苯 (BHT) 的自由基清除性能，但在 100 和 200 μg mL-1 时两种材料之间没有显着差异。此外，该提取物对嗜水气单胞菌的杀菌作用比四环素低近 5 倍。然后，将提取物以 0 (CTL)、0.5 (0.5E)、1 (1E) 和 2 (2E) g kg-1 饲料添加到鱼饲料中。在经受 6 小时拥挤应激之前，用上述饮食喂养这些鱼 60 天。结果表明，提取物对鱼的生长性能没有显着影响（P > .05）。膳食提取物补充剂（1E 和 2E）显着增加血浆超氧化物歧化酶 (P = .003)、过氧化氢酶 (P = .015)、谷胱甘肽过氧化物酶 (P