PHARMACOKINETICS OF A SINGLE DOSE OF ORAL AND SUBCUTANEOUS ENROFLOXACIN IN CARIBBEAN FLAMINGOS (PHOENICOPTERUS RUBER RUBER).

Enrofloxacin is a fluoroquinolone antimicrobial that is widely used in veterinary medicine because of its bactericidal activity and safety in a broad range of species. Caribbean flamingos, a member of the order Phoenicopteriformes, are popular in zoological collections and suffer from a variety of conditions that can result from or lead to bacterial infection. In this study, two groups of 7 adult captive Caribbean flamingos received a single dose of 15 mg/kg enrofloxacin, administered either orally or subcutaneously. Plasma concentrations of enrofloxacin and its metabolite, ciprofloxacin, were measured using liquid chromatography and mass spectrometry. Pharmacokinetic analysis was performed using noncompartmental methods. The pharmacokinetic parameters for both routes of administration were similar, with a mean peak plasma concentration (Cmax) of 5.25 and 5.77 μg/ml, a mean time to peak plasma concentration (Tmax) of 1.49 and 1.1 hr, a mean area under the curve (AUC) of 49.9 and 47.3 hr·μg/ml, and a mean terminal half-life (t1/2) of 5.83 and 6.46 hr for oral and subcutaneous dosing, respectively. Conversion to ciprofloxacin was minimal, with the AUC of ciprofloxacin representing <3% of the enrofloxacin AUC for both routes of administration. Based on the results of the present study, a dose of 15 mg/kg enrofloxacin delivered either orally or subcutaneously in the Caribbean flamingo every 24 hr is recommended for susceptible bacterial pathogens with a minimal inhibitory concentration ≤ 0.25 μg/ml.