The role of dietary lemon peel (LM) and/or Bacillus licheniformis (BL) on the growth, immunity, and resistance against Aeromonas hydrophila in common carp, Cyprinus carpio was investigated in this study. LM and BL were included in diets at 0% (T0), 10⁸ CFU/g BL (T1), 1.5% LM and 10⁸ CFU/g BL (T2), and 3% LM and 10⁸ CFU/g BL (T3). Fish fed with T1, T2, or T3 had higher weight gain, specific growth rate, white blood cells count, and blood total protein with lower feed conversion ratio than T0 group (p < .05). The albumin increased significantly (p < .05) in fish fed both BL and LM (T3). The serum superoxide dismutase (SOD), catalase, lysozyme, and bactericidal activities were significantly increased in fish fed both BL and LM (T2 and T3), while serum glutathione peroxidase increased in fish fed BL (T2) (p < .05). Fish fed T1, T2, and T3 diets displayed higher SOD and lower malondialdehyde than fish fed T0 (p < .05). After the A. hydrophila challenge, the mortality rate was significantly lower in T1, T2, and T3 groups than the T0 group (p < .05). The obtained results revealed that LM and BL could be used to increase resistance against A. hydrophila infection in carp. However, further field studies should be performed to confirm the obtained results.

中文翻译：

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柠檬，桔皮，果皮和地衣芽孢杆菌通过改善体液和皮肤粘膜免疫力以及抗氧化反应，保护鲤鱼不受鲤鱼嗜水气单胞菌感染。

饮食柠檬皮（LM）和/或作用地衣芽孢杆菌（BL）的生长，免疫和抵抗嗜水气单鲤鱼，鲤在这项研究进行了调查。LM和BL分别以0％（T0），10 ⁸ CFU / g BL（T1），1.5％LM和10 ⁸ CFU / g BL（T2）和3％LM和10 ⁸ CFU / g BL（ T3）。用T1，T2或T3喂养的鱼比T0组具有更高的增重，比生长率，白细胞计数和血液总蛋白，饲料转化率也较低（p <.05）。白蛋白显着增加（p≤BL和LM（T3）的鱼<0.05。喂食BL和LM的鱼（T2和T3）的血清超氧化物歧化酶（SOD），过氧化氢酶，溶菌酶和杀菌活性显着增加，而喂食BL（T2）的鱼的血清谷胱甘肽过氧化物酶增加（p <.05）。饲喂T1，T2和T3的鱼比饲喂T0的鱼显示出更高的SOD和更低的丙二醛含量（p <.05）。后嗜水挑战，死亡率为在T1，T2，和T3组显著低于T0组（p <.05）。所得结果表明，LM和BL可用于提高对鲤鱼嗜水曲霉感染的抵抗力。但是，应进行进一步的现场研究以确认获得的结果。