This study evaluated the effects of grape seed extract (GSE) on the growth performance, immune response, and disease resistance of common carp (Cyprinus carpio). Fish were distributed in four groups and fed diets with varying levels of GSE at 0, 10, 20, and 30 g/kg for 56 days. The final length in fish fed with 20 and 30 g GSE/kg diet significantly increased in comparison with the control group (P<0.05). The final weight and weight gain of fish fed with GSE were statistically higher than for the control diet, while the feed conversion ratio was lower in GSE groups than the control. Hematological parameters did not statistically improve with GSE supplemented diets (P>0.05). However, fish fed with 30 g GSE/kg diet displayed a significantly higher WBC count than the other group (P<0.05). The serum total protein and globulin in fish fed with 20 g GSE/kg diet significantly increased compared to the control (P<0.05). A similar pattern was noticed in results for serum and mucus lysozyme activity with a significant increase in fish fed with 20 and 30 g GSE/kg diet compared to the control (P<0.05). Total antibody levels in serum and mucus samples were also increased in fish by dietary GSE with maximum levels by 20 and 30 g GSE/kg diet. Besides, mucus protease activity was higher in fish that received 20 and 30 g GSE/kg diet with maximum level shown in fish fed with 30 g GSE/kg diet compared to the control group (P<0.05). Meanwhile, all groups showed higher mucus antibacterial activity against Aeromonas hydrophila with the highest activity in 30 g GSE/kg diet in comparison with the control group. The cumulative mortality was 36.67% when fish were fed with 30 g GSE/kg diet and challenged with A. hydrophila. However, the mortality rate was 40% and 53.33% in fish fed 20 and 30 g GSE/kg diet, respectively. This study suggests that supplementation of GSE could significantly enhance the growth performance, immune responses, and disease resistance against A. hydrophila in common carp.

中文翻译：

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葡萄籽提取物增强了鲤的生长性能，体液和粘膜免疫力以及鲤鱼对嗜水气单胞菌的抵抗力

这项研究评估了葡萄籽提取物（GSE）对鲤鱼（Cyprinus carpio）的生长性能，免疫反应和抗病性的影响。将鱼分为四组，分别以0、10、20和30 g / kg的GSE水平饲喂日粮，持续56天。与对照组相比，以20和30 g GSE / kg饲料喂养的鱼的最终长度明显增加（P <0.05）。用GSE喂养的鱼的最终体重和增重在统计学上高于对照日粮，而GSE组的饲料转化率低于对照。补充GSE饮食的血液学参数没有统计学改善（P> 0.05）。然而，饲喂30 g GSE / kg饲料的鱼的白细胞计数显着高于另一组（P <0.05）。与对照组相比，以20 g GSE / kg饲料喂养的鱼的血清总蛋白和球蛋白显着增加（P <0.05）。在血清和粘液溶菌酶活性的结果中观察到了类似的模式，与对照组相比，饲喂20和30 g GSE / kg饲料的鱼显着增加了（P <0.05）。饮食中的GSE可使鱼类的血清和粘液样品中的总抗体水平增加，最大水平为20和30 g GSE / kg饮食。此外，饲喂20和30 g GSE / kg饲料的鱼的粘液蛋白酶活性更高，与对照组相比，饲喂30 g GSE / kg饲料的鱼的粘液蛋白酶含量最高（P<0.05）。同时，与对照组相比，在30 g GSE / kg饮食中，所有组均显示出较高的粘液对嗜水气单胞菌的抗菌活性，并具有最高的活性。累计死亡率为36.67％时鱼用30g GSE / kg饲料进料并用挑战嗜水。然而，以20和30 g GSE / kg饲料喂养的鱼的死亡率分别为40％和53.33％。这项研究表明，补充GSE可以显着提高鲤鱼的生长性能，免疫反应和抗亲水性链球菌的抗病性。