作 者：
胡俊茹;王国霞;孙育平;陈冰;曹俊明;黄燕华;卓丽欣
关键词：
硒;黄颡鱼幼鱼;生长性能;抗氧化能力;脂肪代谢基因表达
摘 要：
本试验旨在研究饲料中硒含量对黄颡鱼幼鱼生长性能、抗氧化能力和脂肪代谢基因表达的影响。选用初始体重为(2.12±0.01)g的黄颡鱼幼鱼450尾,随机分为6组,每组设3个重复,每个重复25尾幼鱼,分别投喂硒含量<0.05(对照组)、0.15、0.23、0.35、0.47和0.96 mg/kg的6种等氮等脂试验饲料,饲养期为8周。结果显示:黄颡鱼的增重率随着饲料硒含量的升高呈现先升高后降低的趋势,在饲料硒含量为0.23 mg/kg时达到最高,显著高于对照组(P<0.05)。饲料系数的变化趋势与增重率相反,在饲料硒含量为0.23 mg/kg时达到最低,显著低于对照组(P<0.05)。存活率各组均为100%。全鱼粗蛋白质含量在饲料硒含量为0.35 mg/kg的组最高,显著高于对照组和饲料硒含量为0.23 mg/kg的组(P<0.05)。对照组全鱼粗脂肪含量显著低于饲料硒含量为0.15、0.47和0.96 mg/kg的组(P<0.05),而对照组全鱼水分含量则显著高于饲料硒含量为0.15、0.35、0.47和0.96 mg/kg的组(P<0.05)。血浆胆固醇含量在饲料硒含量为0.23 mg/kg的组最低,显著低于对照组(P<0.05)。全鱼硒含量和肝脏谷胱甘肽过氧化物酶(GPx)活性随着饲料硒含量的增加而升高,二者与饲料硒含量呈正剂量效应关系。肝脏超氧化物歧化酶(SOD)活性随着饲料硒含量由<0.05 mg/kg升高到0.47 mg/kg表现为先升高再降低,而后在饲料硒含量为0.96 mg/kg时又出现升高。对照组肝脏脂蛋白脂酶(LPL)和脂肪酸合成酶(FAS)mRNA的相对表达量显著低于饲料硒含量为0.23 mg/kg的组(P<0.05)。以增重率为评价指标,通过非线性回归分析计算出黄颡鱼幼鱼饲料中硒的适宜含量为0.20 mg/kg。
译 名：
Effects of Dietary Selenium Content on Growth Performance,Antioxidant Capacity and Lipid Metabolism Gene Expression of Juvenile Yellow Catfish(Pelteobagrus fulvidraco)
作 者：
HU Junru;WANG Guoxia;SUN Yuping;CHEN Bing;CAO Junming;HUANG Yanhua;ZHUO Lixin;Institute of Animal Science,Guangdong Academy of Agricultural Sciences;Guangdong Public Laboratory of Animal Breeding and Nutrition;Guangdong Key Laboratory of Animal Breeding and Nutrition;
关键词：
selenium;;juvenile yellow catfish;;growth performance;;antioxidant capacity;;lipid metabolism gene expression
摘 要：
This experiment was conducted to investigate the effects of dietary selenium content on growth performance,antioxidant capacity and lipid metabolism gene expression of juvenile yellow catfish(Pelteobagrus fulvidraco).A total of 450 juvenile yellow catfish with the initial body weight of(2.12±0.01) g were randomly divided into 6 groups with 3 replicates per group and 20 fish per replicate.The fish in those groups were fed6 isonitrogenous and isolipid experimental diets containing <0.05(control group),0.15,0.23,0.35,0.47 and 0.96 mg/kg selenium for 8 weeks,respectively.The results showed as follows:the weight gain rate(WGR) increased firstly and decreased subsequently with dietary selenium content increasing,and the highest value appeared at the 0.23 mg/kg selenium group,which was significantly higher than that in control group(P<0.05).The feed conversion rate(FCR) exhibited an opposite trend to the WGR,and the 0.23 mg/kg selenium group had the lowest value,which was significantly lower than that in control group(P<0.05).The survival ratio in all groups was 100%.The highest whole body crude protein content was found in the0.35 mg/kg selenium group,which was significantly higher than that in control group and 0.23 mg/kg selenium group(P<0.05).The whole body crude lipid content in control group was significantly lower than that in0.15,0.47 and 0.96 mg/kg selenium groups(P<0.05),but the whole body moisture content in control group was significantly higher than that in 0.15,0.35,0.47 and 0.96 mg/kg selenium groups(P<0.05).The plasma cholesterol(CHO) content in 0.23 mg/kg selenium group was the lowest,and was significantly lower than that in control group(P<0.05).The whole body selenium content and liver glutathione peroxidase(GPx) activity were enhanced with dietary selenium content increasing,and presented a dose-response relationship.The liver superoxide dismutase(SOD) activity was firstly increased and then decreased with dietary selenium content increased from <0.05 to 0.47 mg/kg,and then was increased again when dietary selenium content was0.96 mg/kg.The relative expression levels of lipoprotein lipase(LPL) and lipoprotein lipase(FAS) mRNA in control group were significantly lower than those in 0.23 mg/kg selenium group(P<0.05).Using WGR as the evaluation index,the suitable dietary selenium content of juvenile yellow catfish is estimated to be 0.20 mg/kg by nonlinear regression analysis.
