DISPOSITION OF SINGLE-DOSE INTRAVENOUSLY ADMINISTERED ENROFLOXACIN INEMUS (DROMAIUS-NOVAEHOLLANDIAE)

The pharmacokinetics of enrofloxacin in emus (Dromaius novaehollandiae ) were examined following parenteral administration. A mean allometric ally scaled dose of 2.2 +/- 0.03 mg/kg was administered as a single i. v. bolus, and serum samples were collected at predetermined intervals over a 24-hr period. Enrofloxacin levels were measured using high-perf ormance liquid chromatography, and the resulting concentration versus time curve was analyzed using nonlinear regression with least squares parameter estimation. The data were best represented by a two-compartm ent model with a mean elimination half-life of 3.33 hr. Mean model ind ependent parameters obtained were area under the curve (8.26 mu g.hr/m l), mean residence time (4.40 hr), apparent volume of distribution (1. 49 L/kg), and total body drug clearance (0.36 L/hr/kg). Mean serum con centrations exceeded the target peak of 2.0 mu g/ml and remained above an estimated inhibitory concentration of 0.5 mu g/ml for approximatel y 2 hr. Based upon the results of this study, enrofloxacin administere d parenterally to emus at 2.2 mg/kg every 12 hr is expected to achieve therapeutic serum concentrations against susceptible organisms.