外源肌酸对团头鲂生长性能、肠道菌群及血清氨基酸含量的影响

Effect of exogenous creatine on growth performance,intestinal flora and serum amino acid content of Megalobrama amblycephala

试验旨在研究高糖条件下,含有1.20%甜菜碱的饵料中补充0.50%肌酸对团头鲂(Megalobrama amblycephala)生长性能、肠道菌群及血清氨基酸含量的影响。选择180尾平均体重为(11.88±0.46) g的团头鲂,随机分为2组,每组3个重复,每个重复30尾鱼。对照组饵料中包含39.76%碳水化合物+1.20%甜菜碱,不含肌酸;试验组饵料含39.29%碳水化合物+1.20%甜菜碱+0.50%肌酸。试验期90 d。结果表明,与对照组相比,试验组团头鲂的饵料系数显著降低(P<0.05);试验组团头鲂肠道梭杆菌门和变形菌门的占比均显著降低(P<0.05),厚壁菌门占比显著升高(P<0.05);试验组团头鲂肠道的鲸杆菌属、气单胞菌属和弧菌属占比显著降低(P<0.05),ZOR0006和丹毒丝菌科未命名属占比显著升高(P<0.05);试验组团头鲂的血清苏氨酸(Thr)含量显著上升(P<0.05);试验组团头鲂的CK mRNA的表达量显著上升(P<0.05),Tha1 mRNA表达量显著升高(P<0.05)。研究表明,含有1.2%甜菜碱的高糖饵料中补充0.50%的肌酸能够提高团头鲂的饵料利用率,改善其肠道微生物组成及健康,通过苏氨酸醛缩酶增加血清苏氨酸含量。

The experiment was to study the effect of supplementing 0.50% creatine in a diet containing 1.20% betaine on growth performance, intestinal flora and serum amino acid content of Megalobrama amblycephala under high sugar conditions. 180 group Megalobrama amblycephala with an average weight of(11.88±0.46) g were randomly divided into two groups, with three replicates in each group and 30 fish in each replicate. The control bait contained 39.76%carbohydrates + 1.20% betaine and did not contain creatine. The experimental bait contained 39.29% carbohydrates +1.20% betaine + 0.50% creatine. The experiment lasted for 90 d. The results showed that compared with control group, the feed coefficient of experimental group was significantly reduced(P<0.05). The proportions of Fusobacterium and Proteobacteria in experimental group were significantly reduced(P<0.05), the proportion of Firmicutes was significantly increased(P<0.05). The proportions of Cetobacterium, Aeromonas and Vibrio in experimental group were significantly reduced(P<0.05), and the proportions of ZOR0006 and Erysipelotrichaceae-unclassified were significantly increased(P<0.05). The serum threonine(Thr) content of experimental group increased significantly(P<0.05), the mRNA expression of CK of experimental group increased significantly(P<0.05), and the mRNA expression of Tha1 increased significantly(P<0.05). The experiment indicates that supplementing with 0.50% creatine in high-sugar bait containing1.2% betaine can increase the bait utilization rate of Megalobrama amblycephala, improve its intestinal microbial composition and health, and increase the serum threonine content through threonine aldolase.