Pharmacokinetics of cefquinome in crucian carp (Carassius auratus gibelio) after oral, intramuscular, intraperitoneal, and bath administration.

The pharmacokinetics (PK) of cefquinome (CEQ) was studied in crucian carp (Carassius auratus gibelio) after single oral, intramuscular (i.m.), and intraperitoneal (i.p.) administration at a dose of 10 mg/kg body weight and following incubation in a 5 mg/L bath for 5 hr at 25°C. The plasma concentration of CEQ was determined using high-performance liquid chromatography (HPLC). PK parameters were calculated based on mean CEQ concentration using WinNonlin 6.1 software. The disposition of CEQ following oral, i.m., or i.p. administration was best described by a two-compartment open model with first-order absorption. After oral, i.m., and i.p. administration, the maximum plasma concentration (Cmax ) values were 1.52, 40.53, and 67.87 μg/ml obtained at 0.25, 0.23, and 0.35 hr, respectively, while the elimination half-life (T1/2β ) values were 4.68, 7.39, and 6.88 hr, respectively; the area under the concentration-time curve (AUC) values were 8.61, 339.11, and 495.06 μg hr/ml, respectively. No CEQ was detected in the plasma after bath incubation. Therapeutic blood concentrations of CEQ can be achieved in the crucian carp following i.m. and i.p. administration at a dosage of 10 mg/kg once every 2 days.