[Objective]This study investigated the influences of dietary carbohydrate-to-lipid m( CHO)∶m ( L) on growth performance , feed utilization and carbohydrate metabolism enzymes activities of juvenile Chinese sucker , Myxocyprinus asiaticus to detect the suitable addition proportion of m( CHO)∶m( L) to the diet of juvenile Chinese sucker .[Method]Six isonitrogenous ( crude protein 41%) and isoenergetic (16 kJ/g) diets were formulated to contain with graded levels of m( CHO)∶m( L) (0.29,0.81,1.58, 2.88 ,5.46 and 13.22 ) .Each diet was randomly fed to one treatment of Chinese sucker with an average initial body mass of (4.01 ±0.02) g for 8 weeks.Mass gain rate(MGR), specific growth rate (SGR), body composition and carbohydrate metabolism enzymes activities of juvenile Chinese sucker were detec -ted and analyzed .[Result and conclusion]The mass gain rate and specific growth rate increased initially but then decreased with the increasing dietary m( CHO)∶m( L) , thus reaching the highest in fish fed di-ets with m(CHO)∶m(L) of 5.46, which was significantly higher than those of fish fed other diets (P<0.05), whereas feed coefficient rates(FCR) showed a converse trend;the crude lipid content in whole-body of fish decreased with the increasing dietary m(CHO)∶m(L) significantly (P<0.05), while he-patic crude lipid decreased initially and then increased , reaching the lowest level in fish fed diets with m ( CHO)∶m( L) of 2.88; Hepatic triglycercide concentrations increased significantly with the increasing dietary m(CHO)∶m(L) (P<0.05), while activities of aspartate aminotransferase (AST) and alanine aminotransferase ( ALT ) increased initially and then decreased , reaching the peak with dietary m(CHO)∶m(L) of 2.88;lipid content of muscle was lowest in fish fed diet with m(CHO)∶m(L) of 13.22, which was significantly lower than in fish fed diet with m(CHO)∶m(L) of 0.29 (P<0.05).He-patic pyruvate kinase(PK) activities increased significantly with the increasing dietary m(CHO)∶m(L) ( P<0.05 ) , while phosphoenolpyruvate carboxykinase ( PEPCK ) showed a converse trend .No signifi-cant difference was observed in activities of hepatic hexokinase ( HK) and glucose-6-phosphatase ( G-6-pase ) among dietary treatments ( P>0.05 ) .Based on broken-line regression analysis of SGR against di-etary m( CHO)∶m( L) , a m( CHO)∶m( L) of 4.65 was proved to be optimal for the growth of juvenile Chinese sucker .%【目的】研究饲料中碳水化合物（CHO）与脂肪（L）比例[m（CHO）∶m（L）]对胭脂鱼Myxocyprinus asiaticus幼鱼生长、饲料利用及糖代谢酶活力的影响，确定其适宜添加比例．【方法】以m（ CHO）∶m（ L）为0.29、0.81、1.58、2.88、5.46和13.22的6种等氮（粗蛋白质量分数41％）等能（16 kJ/g）饲料，投喂初始体质量为（4.01±0.02） g的胭脂鱼幼鱼8周，测定并分析其对胭脂鱼幼鱼增质量率、特定生长率、鱼体营养成分和糖代谢酶活力等指标的影响．【结果和结论】随着饲料m（CHO）∶m（L）增加，胭脂鱼幼鱼的增质量率和特定生长率先上升后下降，均在m（CHO）∶m（L）为5.46时达到最高，并显著高于其他组（P﹤0.05），饲料系数呈相反趋势；全鱼粗脂肪含量随m（CHO）∶m（L）增加显著下降（P﹤0.05），肝脏粗脂肪则呈先降后升的趋势，在m（CHO）∶m（L）为2.88时达到最低；肌肉粗脂肪含量在m（CHO）∶m（L）为13.22时达最低，且显著低于0.29时（P＜0.05）．随m（CHO）∶m（L）增加，肝脏三酰甘油的含量显著上升（P＜0.05），谷草转氨酶和谷丙转氨酶活力先升高后降低，均在m（CHO）∶m（L）为2.88时达到最高；肝脏丙酮酸激酶活力随m（CHO）∶m（L）增加显著上升（P＜0.05），而磷酸烯醇式丙酮酸激酶活力则呈下降趋势，己糖激酶和葡萄糖-6-磷酸酶活力无显著变化（P＞0.05）．用折线回归模型拟合特定生长率和 m（CHO）∶m（L）的关系，得到胭脂鱼幼鱼获得最大生长时，饲料中m（CHO）∶m（L）为4.65．
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