恩诺沙星控制草鱼维氏气单胞菌的用药方案

Dosing guidelines of enrofloxacin in Ctenopharyngodon idella against Aeromonas veronii

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。

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 CiAVO1. The pharmacodynamics （PD） parameters of enrofloxacin against CiAV01 PK/PD indices are MIC 0. 25μg/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 pharmacoki- netics/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.