PHARMACOKINETICS OF ENROFLOXACIN AFTER SINGLE DOSE ORAL AND INTRAVENOUS ADMINISTRATION IN THE AFRICAN PENGUIN (SPHENISCUS DEMERSUS)

Abstract:  The pharmacokinetics of a single dose of enrofloxacin administered orally, both pilled and in fish, and i.v. to African penguins (Spheniscus demersus) at 15 mg/kg were determined. Plasma concentrations of enrofloxacin and its metabolite ciprofloxacin were measured via high-pressure liquid chromatography with mass spectrometry. An i.v. administration of enrofloxacin resulted in an extrapolated mean plasma concentration of 7.86 μg/ml at time zero. Plasma volume of distribution for i.v. administration was 3.00 L/kg, with a mean elimination half-life of 13.67 hr and a mean total body clearance rate of 3.03 ml/min/kg. Oral administration of enrofloxacin achieved a mean maximum plasma concentration of 4.38 μg/ml at 4.8 hr after administration when pilled, whereas mean maximum plasma concentration was 4.77 μg/ml at 1.59 hr after administration when given in fish. Mean terminal elimination half-life was 13.79 hr pilled and 11.93 hr when given in fish. Low concentrations of ciprofloxacin were detected a...