Comparative pharmacokinetics of norfloxacin nicotinate in common carp ( Cyprinus carpio ) and crucian carp ( Carassius auratus ) after oral administration

Comparative pharmacokinetics of norfloxacin nicotinate ( NFXNT ) was investigated in common carp ( Cyprinus carpio ) and crucian carp ( Carassius auratus ) after a single oral dose of 10 mg/kg body weight (b.w.). Analyses of plasma samples were performed using ultra‐performance liquid chromatography ( UPLC ) with fluorescence detection. After oral dose, plasma concentration–time curves of common carp and crucian carp were best described by a two‐compartment open model with first‐order absorption. The pharmacokinetic parameters of common carp were similar to those of crucian carp. The distribution half‐life ( t 1/2 α ), elimination half‐life ( t 1/2 β ), peak concentration ( C max ), time‐to‐peak concentration ( T max ), and area under the concentration–time curve ( AUC ) of common carp were 1.58 h, 26.33 h, 6069.79 μg/L, 1.08 h, and 103072.36 h·μg/L, respectively, and those corresponding to crucian carp were 1.36 h, 26.55 h, 9586.06 μg/L, 0.84 h, and 126604.4 h·μg/L, respectively. These studies demonstrated that 10 mg NFXNT /kg body weight in common carp and crucian carp following oral dose presented good pharmacokinetic characteristics.