Abstract

The purpose of this study was to determine the pharmacokinetics of meloxicam in Caribbean flamingos (Phoenicopterus ruber ruber). A pilot study was performed first, followed by a complete pharmacokinetic study. Four healthy birds were divided into two groups and administered either 1 mg/kg oral (n=2) or subcutaneous (n=2) meloxicam. Plasma meloxicam concentrations were determined with liquid chromatography/mass spectrometry. Based on the pilot study results, 12 healthy birds were assigned into two groups and administered either a 3 mg/kg oral dose (n=6) or 1.5 mg/kg subcutaneous dose (n=6) of meloxicam. Blood samples were collected at baseline and at nine time intervals after administration of meloxicam in all 12 flamingos. Plasma concentrations after administration of 3 mg/kg oral meloxicam reached a mean C_max of 1.449 µg/ml at 2.35 h with a terminal half-life of 1.832 h. After administration of 1.5 mg/kg subcutaneous meloxicam, C_max was 4.059 µg/ml at 0.91 h with a terminal half-life of 1.104 h. The plasma profile from the principal oral study (3 mg/kg) differed markedly from the pilot study (1 mg/kg), suggesting a delayed absorption with the higher dose and lack of dose proportionality. The different doses for subcutaneous administration resulted in a proportional change in plasma concentrations. Further studies are needed to evaluate the effects of the drug volume administered and fasting status when oral dosing is used. Future studies are also needed to investigate multiple-dose pharmacokinetics of meloxicam and to determine the therapeutic meloxicam plasma concentration in Caribbean flamingos.

Acknowledgments

This study was supported by a grant from the Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University.