残留剂量恩诺沙星对SPF小鼠肠道菌群数量和多样性的影响研究

Effects of residual dose Enrofloxacin on SPF mice intestinal microflora

目的研究不同残留剂量的恩诺沙星对SPF小鼠肠道菌群数量和种类的影响。方法30只SPF雌性KM小鼠,随机分为5组。根据中国现行规定恩诺沙星的日允许摄入量(ADI)设置剂量(0 mg/L、0.03 mg/L、0.3mg/L、3 mg/L、30 mg/L),0.3 mg/L相当于ADI。适应性饲养7 d后给药35 d,恢复21 d。使用活菌计数法检测模型小鼠粪便菌群数量的变化。使用PCR-DGGE法检测粪便菌群多样性的变化。结果3 mg/L和30 mg/L组总需氧菌的数量与对照组比较差异有显著性(P<0.05或P<0.01);30 mg/L组的肠杆菌的数量和对照组比较差异有非常显著性(P<0.01),其余种类细菌数量差异没有显著性。PCR-DGGE结果显示0.3 mg/L的恩诺沙星对小鼠肠道菌群多样性产生影响,3 mg/L和30 mg/L两组影响显著。结论PCR-DGGE技术是一种比活菌计数更灵敏的实验方法,可以用于抗生素残留微生物安全性评价;中国现行规定恩诺沙星的日允许摄入量(ADI)可能会对人体肠道菌群产生影响。

Objective SPF mice had been developed to study the effects of Enrofloxacin on human intestinal flora. Methods 30 SPF KM female mice, five groups were randomly assigned, keeping 7 d, Enrofloxacin was administered via drinking water （0.03 mg/L,0.3 mg/L,3 mg/L,30 mg/L） for 35 d, after cessation of Enrofloxacin, keeping 21 d. Viable count and PCR-DGGE analysis were applied to assess the composition of bacteria population. Results Total aerobic flora counts and enteric bacilli counts decreased significantly following exposure to 30 mg/L Enrofloxacin （ P 〈 0.05 or P 〈 0.01 ）. Total aerobic flora counts were also affected by 3 mg/L Enrofloxacin （ P 〈 0.01 ）. The results of the PCR-DGGE showed that the 0.3 mg/L ,3 mg/L and 30 mg/L Enrofloxacin influenced the diversity of the intestinal flora. Conclusions PCR-DGGE analysis can be applied to assess the impact of residue of antibiotic on diversity of human intestinal flora;The ADI of Enrofloxacin established by Ministry of Agriculture may affect human intestinal microflora.