Florfenicol pharmacokinetics following intravenous and oral administrations and its elimination after oral and bath administrations in common carp (Cyprinus carpio)

The aim of this study was to evaluate pharmacokinetic profiles of florfenicol after a single dose of intravenous (5.00 mg kg-1 body weight) and oral (40.00 mg kg-1 body weight) administrations in common carp (Cyprinus carpio). The residue depletion of florfenicol was also investigated after oral administration (10.00 mg kg-1 body weight) and bath treatment (5.00 mg L-1) for 10 consecutive days. Pharmacokinetics of florfenicol in plasma after a single dose administration, at 10 time points (0.50, 1, 2, 4, 8, 12, 24, 72, 120 and 168 hr) and florfenicol concentrations in tissues (plasma, liver and muscle) at three time points (1, 7 and 14 days) after 10 consecutive days, were analyzed by high performance liquid chromatography. The peak concentration of florfenicol was 137.02 ng mL-1 and the time to reach peak concentration in plasma was two hr. The elimination half-lives, the volume of distribution at steady state and total body clearance were estimated as 21.40 hr, 0.30 and 0.03 L hr-1, respectively. After drug administration for 10 days, it's concentration in plasma and muscle in oral treatment was significantly more than bath treatment in all days. Drug concentrations in the liver after bath treatment were significantly higher for a shorter period than the concentration in the oral treatment, indicating that higher levels of florfenicol for a longer period can be achieved in the tissues after oral drug administration. According to pharmacokinetic results, florfenicol may be a suitable candidate for the treatment of common bacterial infections in common carp farming.