饲料中添加蛋白酶对大口黑鲈生长性能和糖、脂代谢的影响  

Effects of Dietary Protease on Growth Performance,Glucose and Lipid Metabolism of Largemouth Bass(Micropterus salmoides)

作　　者：关莹 薛继鹏 薛敏[1] 谢晓泽 吴秀峰[1] 郑银桦[1] 梁晓芳[1] GUAN Ying;XUE Jipeng;XUE Min;XIE Xiaoze;WU Xiufeng;ZHENG Yinhua;LIANG Xiaofang(The National Aquatic Feed Safety Assessment Center,Feed Research Institue,Chinese Academy of Agricultural Sciences,Beijing 100081,China;Key Laboratory of Applied Biology and Aquaculture Northern Fish in Liaoning Province,Dalian Ocean University,Dalian 116023,China;Guangzhou Bosio Biochemical Technology Research Co.,Ltd.,Guangzhou 511356,China)

机构地区：[1]中国农业科学院饲料研究所,国家水产饲料安全评价基地,北京100081 [2]大连海洋大学,辽宁省北方鱼类应用生物学与增养殖重点实验室,大连116023 [3]广州市博仕奥生化技术研究有限公司,广州511356

出　　处：《动物营养学报》2021年第10期5974-5988,共15页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家重点研发计划(2019YFD0900200,2018YFD0900400);国家自然科学基金(31902382,31802306);北京市自然科学基金(6204047);中国农业科学院创新工程项目(CAAS-ASTIP-2017-FRI-08);北京市现代农业产业技术体系(BAIC08-2021)。

摘　　要：本试验旨在研究饲料中添加蛋白酶对大口黑鲈生长性能及糖、脂代谢的影响。试验将初始体重为(31.39±0.05)g的大口黑鲈幼鱼240尾,随机分为2个对照组和2个试验组,每组3个重复,每个重复20尾鱼。饲喂鱼粉含量为50%的饲料作为正对照(HFM组),鱼粉含量为30%、棉籽浓缩蛋白(CPC)替代40%鱼粉蛋白的饲料作为基础对照(LFM组);试验组是在LFM组饲料的基础上分别添加4500(LFM+E4500组)和7500 U/kg蛋白酶(LFM+E7500组)。各组饲料的必需氨基酸和必需脂肪酸进行了平衡。养殖周期为65 d。结果表明:1)CPC替代40%鱼粉蛋白后,基础能量代谢水平与HFM组相比显著降低(P<0.05)。2)添加蛋白酶后,存活率有一定程度的上调(由LFM组的92.50%上调到LFM+E4500组的98.33%和LFM+E7500组的100.00%);试验组鱼体腹脂率与LFM组相比显著下降(P<0.05),可以使鱼体可食用部分增加,极大地提高了大口黑鲈的商业价值和经济效益。3)与LFM组相比,试验组前、后肠蛋白酶含量显著提高(P<0.05),从而提高鱼体对蛋白质的消化吸收能力。饲料中添加4500 U/kg蛋白酶提高了肝脏糖异生酶磷酸烯醇式丙酮酸羧激酶(PEPCK)、葡萄糖-6-磷酸酶(G6Pase)的活性,有助于空腹状态下糖异生相关酶的正常表达,维持饥饿状态下血糖浓度的相对恒定;肝脏中升高的环磷酸腺苷(cAMP)含量上调了环磷腺苷效应元件结合蛋白(CREB)mRNA相对表达量,从而使肝脏脂解过程的酶[脂肪甘油三酯脂肪酶(ATGL)、单酰甘油脂肪酶(MGL)]、腹脂脂解过程的酶[ATGL和激素敏感性脂肪酶(HSL)]活性和mRNA相对表达量显著上调(P<0.05),加速脂解。综上所述,在低鱼粉基础饲料中添加4500 U/kg的蛋白酶,可进一步提高大口黑鲈的基础能量代谢水平和前、后肠蛋白酶含量,促进空腹状态下糖代谢关键酶的正常表达,并可以减少肝脏和鱼体脂质积累,但过量添加蛋白酶(7500 U/kg)会降低鱼体蛋白质沉积率,提高�The objectives of the study were to investigate the effects of dietary protease(NP)on growth performance,glucose and lipid metabolism of largemouth bass.A total of 240 Juvenile largemouth bass with an initial body weight of(31.39±0.05)g were randomly divided into two control groups and two experimental groups,with three replicates in each group and 20 fish in each replicate.The diet containing 50%fish meal(HFM group)was used as a positive control.The basal control diet(LFM group)contained 30%fish meal and 40%fish meal protein replaced by cottonseed protein concentrate(CPC).The experimental group was fed LFM group diet with 4500(LFM+E4500 group)and 7500 U/kg NP(LFM+E7500 group).The essential amino acids and essential fatty acids were balanced in each group,and the feeding period was 65 days.The results showed as follows:1)compared with HFM group,the level of basal energy metabolism in CPC group was significantly lower than that in HFM group(P<0.05).2)The survival rate was up-regulated to a certain extent(from 92.50%in LFM group to 98.33%in LFM+E4500 group and 100.00%in LFM+E7500 group)with protease adding.Compared with the LFM group,the abdominal fat rate of the experimental group decreased significantly(P<0.05),and the edible part of the fish increased,which greatly improved the commercial value and economic benefits of largemouth bass.3)Compared with LFM group,the protease content in the intestine of the experimental group was significantly increased(P<0.05),so as to improve the digestion and absorption of protein.The activities of phosphoenolpyruvate carboxykinase(PEPCK)and glucose-6-phosphatase(G6Pase)in liver were increased by adding 4500 U/kg protease,which was helpful to the normal expression of gluconeogenesis related enzymes in fasting state and maintain the relative constant blood glucose content in a hungry state.The increased cyclic adenosine monophosphate(cAMP)content in the liver upregulated the mRNA relative expression of cAMP-response element binding protein(CREB),thus,the activities of the enzyme

关 键 词：大口黑鲈 中性蛋白酶 生长性能 蛋白质代谢 糖、脂代谢 

分 类 号：S963[农业科学—水产养殖]