PHARMACOKINETICS OF AMIKACIN IN SCIMITAR-HORNED ORYX (ORYX DAMMAH) FROM A SINGLE INTRAVENOUS DOSE

Single-dose pharmacokinetics of amikacin in seven adult scimitar-horne d oryx (Oryx dammah) was determined. The intravenous dose of 5.8 mg/kg (mean) was based on metabolic energy scaling. Blood samples were coll ected through an indwelling jugular catheter at 0, 5, 15, 30, 45, 60, 75, 90, 120, 240, 300, 360, 480, 600, 720, and 1,440 min after amikaci n administration. Drug-concentration-versus-time curves were best fit to a two-compartment open model with a maximum serum concentration aft er distribution of 30.5 +/- 4.7 mu g/ml and a mean elimination half-li fe of 97.0 +/- 31.8 min. Model-independent parameters were: area under the curve, 5,478 +/- 2,828 mu g/min/ml; volume of distribution (stead y state), 0.152 +/- 0.02 L/kg; clearance, 1.2 +/- 0.4 ml/min/kg; and m ean residence time, 136.5 +/- 49.0 min. Mean serum amikacin concentrat ions reached the recommended peak concentration (25 mu g/ml) then fell below the recommended trough concentration (2 mu g/ml) by 8 hr after administration. The serum amikacin concentrations were above the minim um inhibitory concentration (MIG) levels of selected bacteria for up t o 6 hr. Based on this study, amikacin administered parenterally to sci mitar-horned oryx at 5.8 mg/kg at 12-hr intervals should produce thera peutic serum concentrations for susceptible bacteria.