Single intravenous and oral dose pharmacokinetics of florfenicol in the channel catfish ( Ictalurus punctatus )

Gaunt, P. S., Langston, C., Wrzesinski, C., Gao, D., Adams, P., Crouch, L., Sweeney, D., Endris, R. Single intravenous and oral dose pharmacokinetics of florfenicol in the channel catfish ( Ictalurus punctatus ). J. vet. Pharmacol. Therap .  35 , 503–507. Plasma distribution and elimination of florfenicol in channel catfish were investigated after a single dose (10 mg/kg) of intravenous (i.v.) or oral administration in freshwater at a mean water temperature of 25.4 °C. Florfenicol concentrations in plasma were analyzed by means of liquid chromatography with MS/MS detection. After i.v. florfenicol injection, the terminal half‐life ( t 1/2 ), volume of distribution at steady state ( V ss ), and central volume of distribution ( V c ) were 8.25 h, 0.9 and 0.381 L/kg, respectively. After oral administration of florfenicol, the terminal t 1/2 , C max , T max , and oral bioavailability ( F ) were 9.11 h, 7.6 μg/mL, 9.2 h, and 1.09, respectively. There was a lag absorption time of 1.67 h in oral dosing. Results from these studies support that 10 mg florfenicol/kg body weight in channel catfish is an efficacious dosage following oral administration.