Pharmacokinetics of florfenicol in Japanese eel (Anguilla japonica) after a single oral dose

Florfenicol has been approved to specially used in livestock and aquatic animals including eels. The present study provides a better understanding of florfenicol deposition in Japanese eel (Anguilla japonica) following oral administration of a single dose of 30 mg/kg at 25°C. The pharmacokinetics parameters were calculated by both noncompartmental and compartmental operations using DAS software. The plot of florfenical concentration-time in plasma after oral dose is fitted by a two-compartment open model. In noncompartmental analysis, kinetics parameters of maximum concentration (C_max), time to C_max (T_max), mean residence time (MRT), half-life of drug (t_1/2), volume of distribution (Vd) and clearance (CL) were calculated to be 15.920 μg/ml, 4 h, 18.370 h, 12.341 h, 2.078 L/kg and 0.117 L/kg/h, respectively. Based on the pharmacokinetic profiles provided in this study and the investigation of minimum inhibitory concentration (MIC) against the infectious bacteria reported previously, it is proposed that two dose of 30 mg/kg one day would be acceptable for treatment of eel with bacterial infections.