为了探讨海带粉对克氏原螯虾Procambarus clarkii生长、非特异性免疫和肝胰脏抗氧化能力的影响,选取体质量为(7.25±0.24)g的克氏原螯虾随机分成5组,每组设3个平行,每个平行放20只虾.其中一组为对照组,投喂基础饲料;另外4组为试验组,投喂基础饲料中分别添加质量分数为0.5%、1.0%、2.0%、4.0%海带粉的饲料.饲养8周后,测定克氏原螯虾的生长性能及血液和肝胰脏生化指标.结果表明:海带粉对克氏原螯虾死亡率和增重率均有显著性影响(P<0.05),当添加量为2.0%时增重率最高,成活率则随着添加量的增加而提高;随着饲料中海带粉添加量的增加,试验组虾血清中的溶菌酶活性、总蛋白浓度均呈先上升后降低的趋势,当添加量为2.0%时均达到最大值,碱性磷酸酶活性在海带粉添加量为1.0%时达到最大值;随着海带粉添加量的增加,肝胰腺中的超氧化物歧化酶、过氧化氢酶和谷胱甘肽活性均呈先升高后降低的趋势,超氧化歧化酶活性在添加量为2.0%时达到最大值,过氧化氢酶和谷胱甘肽活性在添加量为1.0%时均达到最大值,丙二醛含量则呈相反的变化趋势.研究表明,饲料中添加1.0%~2.0%的海带粉可以显著提高虾的生长性能、免疫功能和肝胰脏抗氧化能力,建议克氏原螯虾饲料中添加1.0% ~2.0%的海带粉.
Juvenile red swamp crayfish Procambarus clarkii with body weight of (7.25±0.24)g was randomly divided into five groups and fed basal diet (control group) and the basal diets supplemented with 0.5%,1.0%,2.0%,and 4.0% of kelp powder (treatment groups) at water temperature of (25 ± 3) ℃ with triplication for 8 weeks to evaluate the effects of kelp powder on the growth,non-specific immunity and heptaopancreatic antioxidant capacity in red swamp crayfish.The results showed that the survival rate and weight gain rate of the crayfish were significantly affected by the kelp powder (P〈0.05),the best growth in the crawfish fed the diet containing 2.0%of kelp powder,and increase in survival with increase in dietary kelp powder.The serum lysozyme activity,and total protein level were found to be increased and then decreased with increase in dietary kelp powder level,the maximum at 2.0% dietary kelp powder group,and the maximal serum alkaline phosphatase activity at 1.0% dietary kelp powder group.The activities of hepatopancreatic superoxide dismutase,catalase and glutathione showed a trend of increase and then decrease with the increase in the addition of kelp powder,the maximal superoxide dismutase activity at 2.0% dietary kelp powder group,the maximal catalase and glutathione activities and the minimal malondialdehyde level at 1.0% dietary kelp powder group.In conclusion,1.0% to 2.0% dietary kelp powder led to significant improvement of growth performance,immunity and hepatopancreatic antioxidant capacity in the crawfish,and was recommended to be used in the crawfish feed.