不同水平蚯蚓虫沙对鲤生长、消化和抗氧化指标影响

Effects of dietary vermicompost on growth performance, digestive enzyme activity and antioxidant indices in common carp Cyprinus carpio

为研究基础饲料中添加不同水平蚯蚓虫沙对鲤Cyprinus carpio生长性能、血清及肝胰脏抗氧化指标和消化酶的影响,对蚯蚓虫沙营养价值及安全性进行了分析评估,在水温27~29℃下,选用同一批次初始体质量为(73.66±0.21)g的鲤幼鱼336尾,随机分成8组,每组设3个重复,分别为饲喂基础饲料的A组,添加2.5%、5.0%、7.5%晒干蚯蚓虫沙的混合饲料B1、B2和B3组,添加5.0%、7.5%高温烘干蚯蚓虫沙的混合饲料C1和C2组,以及添加晒干蚯蚓虫沙+蚯蚓粉(5.0%+0.15%、7.5%+0.23%)的混合饲料D1和D2组,在室内玻璃水族箱(100 cm×50 cm×50 cm)中进行生长试验,饲养60 d后测定鲤生长、消化酶和血清及肝胰脏抗氧化指标。结果表明:试验饲料中添加蚯蚓虫沙后重金属含量远低于《饲料卫生标准》,用量安全;蚯蚓虫沙添加量不同,对鲤增重率、特定生长率及血清和肝胰脏抗氧化指标均有一定影响,除2.5%添加量与对照组无显著性差异(P>0.05)外,其余各试验组超氧化物歧化酶(T-SOD)与对照组均有显著性差异(P<0.05),其中以晒干蚯蚓虫沙5.0%添加量最好,增重率、特定生长率、T-SOD水平均显著高于对照组(P<0.05);不同添加量的蚯蚓虫沙对鲤肠道消化酶及饲料系数均无显著性差异(P>0.05)。研究表明,饲料中添加一定量的蚯蚓虫沙能够显著提高鲤的生长性能和血清、肝胰脏中T-SOD水平,降低丙二醛(MDA)含量。

A total of 336 individuals of common carp Cyprinus carpio with an initial body weight of(73.66±0.21)g were randomly divided into 8 groups with 3 replicates per group,14 fish per replicates,reared in an indoor tank of 100 cm×50 cm×50 cm and fed basal diet(control group A),and the basal diets supplemented with sun-dried vermicompost,whose nutritional level and safety were evaluated,at a rate of 2.5%(group B1),5.0%(group B2),and 7.5%(group B3),and with high-temperature dried vermicompost at a rate of 5.0%(group C1),and 7.5%(group C2),and with mixture of sun-dried vermicompost and earthworm powder at a ratio of 5.0%+0.15%(group D1),and 7.5%+0.23%(group D2)at water temperature of 27-29℃for 60 d.The growth performance digestive enzyme activity and antioxidant indices in serum and hepatopancreas ofcommon carp were determined at the end of the experiment.The results showed that the contents of heavy metals in the common carp fed the diets containing vermicompost were well under the level of hygienical standard for feeds,and the different levels of additional vermicompost showed certain effects on the weight gain rate,specific growth rate,serum and antioxidative indices in serum and hepatopancreas,significant differences in superoxid dismutase activity between the treatment groups and the control group(P<0.05)except for B1 group.There was no significant difference in food conversion ratio and activities of intestinal digestive enzymes among the fish fed the diets containing different levels of vermicompost(P>0.05).The findings provided theoretical reference and data for reasonable application and development of vermicompost as feed additives in aquaculture.