饲料蛋白水平对大口黑鲈稚鱼生长、肠道结构及耐离水胁迫能力的影响  

Effects of dietary protein levels on growth,intestinal structure and air exposure tolerance in juvenile largemouth bass(Micropterus salmoides)

作　　者：覃瑶 李诗洋 梁浩辉 陈晓瑛 黄燕华 周萌 王国霞 QIN Yao;LI Shi-yang;LIANG Hao-hui;CHEN Xiao-ying;HUANG Yan-hua;ZHOU Meng;WANG Guo-xia(Institute of Animal Science,Guangdong Academy of Agricultural Sciences/Key Laboratory of Animal Nutrition and Feed in South China,Ministry of Agriculture and Rural Affairs/Key Laboratory of Animal Breeding and Nutrition Research of Guangdong,Guangzhou,Guangdong 510640,China;College of Oceanography,South China Agricultural University,Guangzhou,Guangdong 510642,China;College of Animal Science and Technology/Innovation Institute of Healthy Breeding,Zhongkai University of Agriculture and Engineering,Guangzhou,Guangdong 510225,China)

机构地区：[1]广东省农业科学院动物科学研究所/农业农村部华南动物营养与饲料重点实验室/广东省畜禽育种与营养研究重点实验室,广东广州510640 [2]华南农业大学海洋学院,广东广州510642 [3]仲恺农业工程学院动物科技学院/健康养殖创新研究院,广东广州510225

出　　处：《南方农业学报》2024年第12期3758-3769,共12页Journal of Southern Agriculture

基　　金：广东省重点领域研发计划项目(2021B0202050002);广州市基础研究计划民生科技专题项目(202002020018)。

摘　　要：【目的】探究不同饲料蛋白水平对大口黑鲈(Micropterus salmoides)稚鱼生长性能、肠道结构及耐离水胁迫能力的影响和大口黑鲈稚鱼对饲料蛋白的需求,为大口黑鲈稚鱼饲料的研发提供理论参考。【方法】配制实测蛋白含量分别为45.02%、48.14%、52.12%、55.54%、56.26%和58.17%的6种等脂等能饲料。选取2880尾初始体重为0.07±0.00 g的大口黑鲈稚鱼,随机分为6组,分别饲喂配制的6种等脂等能饲料,按照饲料蛋白水平由低到高设为T1、T2、T3、T4、T5、T6组,试验周期30 d。试验开始前随机选取50尾大口黑鲈稚鱼用于测定初始鱼体成分。试验结束后禁食24 h,每组随机取9尾大口黑鲈稚鱼测量体长,称量体质量及内脏团质量用于计算形体指标。每组随机取30尾大口黑鲈稚鱼于冰上解剖,取全肠和肝脏,用以检测消化酶和抗氧化酶活力。每组随机取2尾大口黑鲈稚鱼于冰上解剖,分离肠道,置于4%多聚甲醛中固定,用于制作组织切片。每组随机取20尾大口黑鲈稚鱼,用于测定鱼体成分。使用TRIzol法提取大口黑鲈稚鱼肌肉与肠道组织总RNA,并利用实时荧光定量PCR检测大口黑鲈稚鱼生长与抗氧化相关基因的相对表达量。【结果】随着饲料蛋白水平升高,大口黑鲈稚鱼的增重率和特定生长率呈先升高后降低的趋势,饲料系数则呈先降低后升高的趋势,其中T4组大口黑鲈稚鱼特定生长率显著高于T2、T3、T5和T6组(P<0.05,下同),T3组肝脏胰蛋白酶活力最高,显著高于T6组。离水胁迫处理后,T4组过氧化氢酶(CAT)和总超氧化物歧化酶(T-SOD)活力最高,丙二醛(MDA)含量最低。实时荧光定量PCR结果显示,各组间生长相关基因IGF1、S6K、4EBP1和抗氧化相关基因CAT1的相对表达量无显著差异(P>0.05)。【结论】适宜饲料蛋白水平能提高大口黑鲈稚鱼的饲料利用效率,增加其增重率、特定生长率、蛋白沉积率和脂肪沉积率,进而获得�【Objective】The purpose of this study was to investigate the effects of different dietary protein levels in feed on the growth performance,intestinal health and air exposure resistance of juvenile largemouth bass(Micropterus salmoides).【Method】Six isoenergetic diets with actual protein contents of 45.02%,48.14%,52.12%,55.54%,56.26%and 58.17%were configured.A total of 2880 juvenile M.salmoides with an initial body weight of 0.07±0.00 g were randomly divided into 6 groups,which were fed with 6 kinds of isolipids and isoenergetic diets respectively,and were divided into groups T1,T2,T3,T4,T5 and T6 according to the dietary protein levels from low to high.The experiment lasted for 30 d.Before the experiment,50 juvenile M.salmoides were randomly selected to determine the initial composition of the fish.After fasting for 24 h,9 juvenile M.salmoides were randomly taken from each group to measure body length,weigh body mass and visceral mass weight to calculate body indexes.Thirty juvenile M.salmoides from each group were dissected on the ice,and the whole intestines and liver were taken to detect the activities of digestive enzymes and antioxidant enzymes.Two juvenile M.salmoides were dissected on ice at random in each group,and the intestines were isolated and fixed in 4%paraformaldehyde for the preparation of tissue sections.Twenty juvenile M.salmoides were randomly selected from each group to determine the composition of the fish body.Total RNA was extracted from muscle and intestinal tissues of M.salmoides by TRIzol method,and the relative expression of genes related to growth and antioxidant in M.salmoides larvae was detected by real-time fluorescence quantitative PCR.【Result】The results showed that with the increase of protein level in the diet,the weight gain rate,specific growth rate of juvenile M.salmoides showed a trend of first increasing and then decreasing,and feed conversion rate(FCR)was decreased first and then increased,among which the specific growth rate of T4 group were the significantly h

关 键 词：大口黑鲈稚鱼 生长性能 肠道结构 离水胁迫 

分 类 号：S965.211[农业科学—水产养殖]