芡实提取物对克氏原螯虾生长、抗氧化能力及免疫功能的影响

Effect of Euryale ferox extract on growth,antioxidant capacity,and immunity of Procambarus clarkii

为探究芡实(Euryale ferox)提取物对克氏原螯虾(Procambarus clarkii)生长免疫的影响,本实验按照饲喂饲料芡实提取物的添加浓度分为对照组(0 g/kg)、0.5%芡实组(5 g/kg)、1%芡实组(10 g/kg)和2%芡实组(20 g/kg),连续投喂克氏原螯虾28 d,实验结束后测定克氏原螯虾的生长参数和嗜水气单胞菌攻毒后的存活率,并分析了抗氧化酶活、免疫相关酶活和相关基因表达情况。结果显示:芡实提取物对克氏原螯虾的生长和嗜水气单胞菌攻毒后的存活率没有影响。与对照组相比,0.5%芡实饲喂显著增加了克氏原螯虾血清中的酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活性,而1%和2%芡实血清中的ACP活性显著降低,2%芡实组克氏原螯虾血清中的SOD活性显著增加。在肝胰腺中,0.5%芡实组克氏原螯虾的ACP活性也显著增加,但其它酶活没有显著变化。荧光定量PCR的结果显示,2%芡实显著增加了克氏原螯虾CypA和GPxs mRNA的表达,而Astacidin mRNA的表达在各组之间均无显著差异。综上结果表明,芡实提取物能在一定程度上增强克氏原螯虾的抗氧化能力和免疫力,而不影响其生长。

This experiment was divided into control group(0 g/kg),0.5%-EF group(5 g/kg),1%-EF group(10 g/kg),and 2%-EF group(20 g/kg)according to the added concentration of EF extract to explore the effect of Euryale ferox(EF)extract on the growth and immunity of Procambarus clarkii.Followed by consecutive 28 days of feeding,we observed the changes in growth parameters of crayfish and the survival rate after Aeromonas hydrophila challenge.The activity of antioxidant or immunology-related enzymes and the expression of immunology-related genes in crayfish were also measured.The results showed no significant effect of EF extract on the growth index and the survival rate after being attacked by A.hydrophila..Compared with the control group,0.5%-EF significantly increased the ACP and AKP activities in the serum of crayfish,while 1%-EF and 2%-EF decreased the ACP activity,and the SOD activity in the 2%-EF group were significantly increased.In the hepatopancreas of crayfish,the ACP activity in the 0.5%-EF group was also increased significantly,but the activities of SOD,CAT and AKP had no change.The results of real-time PCR showed that 2%-EF significantly increased the CypA and GPxs mRNA expression,while the Astacidin mRNA expression did not vary significantly between different groups.These results suggested that the EF extract could enhance crayfish's immunity and antioxidant capacity to a certain extent with no effect on their growth.