杜仲皮、叶对草鱼生长、肌肉品质及胶原蛋白相关基因表达的影响

Influences of Dietary Eucommia Bark and Leaf on Growth,Muscle Quality and Collagen Related Genes Expression in Grass Carp(Ctenopharyngodon idellus)

为考察杜仲对草鱼生长、肌肉品质和胶原蛋白相关基因表达的影响,本试验选取平均体重为(59.7±0.3)g的草鱼162尾,随机分为3组,每组3个重复,每个重复18尾。对照组饲喂基础饲料,其他2组在基础饲料中分别添加20 g/kg的杜仲皮(EB)和40 g/kg杜仲叶(EL)。饲养周期为60 d。结果表明:EB和EL组的增重率分别为293.4%、300.0%,分别较对照组显著升高3.38%、5.71%(P<0.05),饲料系数分别显著降低0.06、0.10(P<0.05)。与对照组相比,EB和EL组的肌肉钙、总胶原蛋白和热不溶性胶原蛋白含量显著增加(P<0.05),肌肉脂肪含量显著降低(P<0.05)。饲料中添加EB和EL显著提高了肌肉总氨基酸和必需氨基酸指数(P<0.05)。此外,饲料中添加EB和EL还显著降低了血清葡萄糖、总胆固醇和甘油三酯含量(P<0.05)。在胶原蛋白相关基因表达方面,EB和EL显著上调了肌肉Ⅰ型胶原蛋白α1(COL1A1)、Ⅰ型胶原蛋白α2(COL1A2)和赖氨酸氧化酶(LOX)基因相对表达量(P<0.05),显著下调了肌肉基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)基因相对表达量(P<0.05)。此外,EL组的肌肉脯氨酸羟化酶(PHD)基因相对表达量也显著提高(P<0.05)。综上所述,EB和EL可以改善草鱼生长性能,降低脂肪沉积,并通过上调胶原蛋白合成相关基因和降低胶原蛋白分解相关基因的表达而提高肌肉胶原蛋白含量。

The study investigated the effects of dietary Eucommia ulmoides on growth,muscle quality and collagen related genes expression of grass carp(Ctenopharyngodon idella).A total of 162 grass carp with average body weight of(59.7±0.3)g were selected and divided into 3 groups with 3 replicates in each group and 18 grass carp in each replicate.Control group was fed a basal diet,and the other groups were fed the basal diet with 20 g/kg Eucommia bark(EB)and 40 g/kg Eucommia leaf(EL),respectively.The feeding period was 60 days.The results showed as follows:the weight gain rate of EB and EL groups were 293.4%and 300.0%,and were significantly increased by 3.38%and 5.71%compared with control group(P<0.05),and the feed conversion ratio were significantly decreased by 0.06 and 0.10(P<0.05).Compared with the control group,dietary EB and EL significantly increased the contents of calcium,total collagen and heat-insoluble collagen in muscle(P<0.05),and significantly decreased muscle lipid content(P<0.05),and the total amino acids content and essential amino acid index in muscle also significantly increased(P<0.05).In addition,the serum glucose,total cholesterol and triglycerides contents of the two groups were lower than those of the control group(P<0.05).In collagen related genes expression,the EB and EL supplementation significantly promoted the relative transcript levels ofⅠtype collagenα1(COL1A1),Ⅰtype collagenα2(COL1A2)and lysyl oxidase(LOX)genes in muscle(P<0.05),while the relative transcript levels of matrix metalloproteinase-2(MMP-2)and matrix metalloproteinase-9(MMP-9)genes significantly decreased(P<0.05).Moreover,dietary EL also significantly increased the relative transcript level of prolyl hydroxylase(PHD)gene(P<0.05).In conclusion,dietary EB and EL improve the growth performance,decrease muscle lipid deposition of grass carp,and increase collagen content in muscle by up-regulating the expression of collagen synthesis-related genes and down-regulating the expression of collagen degradation-related genes.