The study explored the effects of extract of mulberry leaves (EML) on the growth performance and hypoxia-reoxygenation stress as well as biochemical parameters in various organs of crucian carp (). The results indicated that dietary EML improved the growth of crucian carp. The appropriate concentration of EML for fish growth was estimated to be 46.93 g kg diet. Moreover, dietary EML raised the digestive, absorptive and metabolic function by improving feed intake and alpha‐amylase, lipase, trypsin, alkaline phosphatase, glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase activities in hepatopancreas or intestine and decreasing plasma ammonia content, and respiratory function by increasing GOT activities in the branchiae and hemoglobin level in red blood cells of crucian carp. After 30 days feeding trial, crucian carp was treated with hypoxia-reoxygenation. The result showed that dietary EML improved hypoxia tolerance in crucian carp. The appropriate concentration of EML for hypoxia tolerance was estimated to be 57.21 g kg diet. Hypoxia-reoxygenation stimulated the loss of partial digestive, absorptive, respiratory and metabolic function, reactive oxygen species (ROS) generation and cellular component oxidation in the digestive and respiratory organs, suggesting the ability of hypoxia-reoxygenation to induce oxidative lesion in fish. However, dietary EML reduced the oxidative lesion in a way of suppressing the production of ROS and oxidation of cellular component and elevating activities of enzymatic antioxidant and levels of non-enzymatic antioxidant in the digestive and respiratory organs of fish caused by hypoxia-reoxygenation. Therefore, EML can be utilized as an inhibitor of hypoxia-reoxygenation stress in fish.

中文翻译：

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桑叶饲料提取物对鱼类生长性能、缺氧复氧应激及各器官生化参数的影响


本研究探讨了桑叶提取物（EML）对鲫鱼生长性能、缺氧复氧应激以及各器官生化参数的影响。结果表明，饲料EML促进了鲫鱼的生长。鱼类生长所需的 EML 适宜浓度估计为 46.93 g/kg 饲料。此外，日粮EML通过改善采食量以及肝胰腺或肠道中的α-淀粉酶、脂肪酶、胰蛋白酶、碱性磷酸酶、谷氨酸-草酰乙酸转氨酶（GOT）和谷氨酸-丙酮酸转氨酶活性以及降低血浆氨含量来提高消化、吸收和代谢功能通过提高鲫鱼鳃中GOT活性和红细胞中血红蛋白水平来改善呼吸功能。经过30天的饲养试验，对鲫鱼进行缺氧-复氧处理。结果表明，饲料EML提高了鲫鱼的耐缺氧能力。耐缺氧的 EML 适当浓度估计为 57.21 g/kg 饮食。缺氧复氧刺激了消化和呼吸器官部分消化、吸收、呼吸和代谢功能的丧失、活性氧（ROS）的产生和细胞成分氧化，表明缺氧复氧能够诱导鱼类氧化损伤。然而，日粮EML通过抑制ROS的产生和细胞成分的氧化，提高缺氧复氧引起的消化和呼吸器官中酶抗氧化剂的活性和非酶抗氧化剂的水平，从而减轻氧化损伤。因此，EML 可用作鱼类缺氧-复氧应激的抑制剂。