恩诺沙星控制草鱼维氏气单胞菌的用药方案

从四川成都一养殖场大规模发病死亡的草鱼(Ctenopharyngodon idella)病灶处分离一株病原菌CiAV01,结合形态学和16S rDNA序列分析,鉴定该菌为维氏气单胞菌(Aeromonas veronii)。回归感染实验结果表明,分离菌株感染草鱼致死率为100%,出现了局部出血、腹腔积水等症状。采用琼脂平板扩散法研究了16种抗生素对分离菌株CiAV01的体外抑菌作用,在供试的抗生素中,恩诺沙星对该分离菌株CiAV01最为敏感。选择恩诺沙星对分离菌株进行体外药效学研究表明,恩诺沙星对分离菌株CiAV01的最小抑菌浓度(MIC)为0.25μg/mL,最小杀菌浓度(MBC)为0.50μg/mL,MBC/MIC为2。结合其药物动力学参数和MIC、MBC、防突变浓度(MPC)、突变选择窗(MSW)和抗菌后效应(PAE)制定防突变给药方案为:剂量20 mg/kg、每日一次给药、连续给药3～5 d。

Dosing guidelines of enrofloxacin in Ctenopharyngodon idella against Aeromonas veronii

A pathogenic bacterical strain CiAV01 was isolated from naturally infected Ctenopharyngodon idella in a fish farm in Sichuan province.The strain CiAV01 was identified as Aeromonas veronii,according to its physiological and 16S rDNA sequence.Recurrent infection showed that the mortality of Ctenopharyngodon idella is 100% after artificial infect healthy Ctenopharyngodon idella with the symptoms of hemorrhage and ascites.The drug sensitivity of 16 antibiotics was studied using Kirby-Bauer's ager diffusion method,and enrofloxacin was the most highly sensitive to the strain CiAV01.The pharmacodynamics(PD) parameters of enrofloxacin against CiAV01 PK/PD indices are MIC 0.25 μg/mL,MBC 0.50 μg/mL,MBC/MIC 2,MPC,MPC 2 μg/mL and MSW 0.25~2.0 μg/mL,respectively.Based on pharmacokinetics/pharmacodynamics parameters,and MIC,MBC,MPC,MSW and PAE,once-daily dose of 20 mg/kg for 3~5 days was determined to be optimal for controlling Aeromonas veronii CiAV01 infection and simultaneously preventing mutant selection in grass carp based on pharmacokinetics/pharmacodynamics parameters and MIC,MBC,MPC,MSW,PAE.