Comparative pharmacokinetics of meloxicam in sheep and buffalo calves following intravenous administration

Present study describes the comparative pharmacokinetic profile of meloxicam following intravenous administration (0.5 mg.kg⁻¹) in buffalo calves and sheep. Plasma concentration of meloxicam was determined by HPLC assay and pharmacokinetic parameters were calculated by two compartmental open method using an interactive least- square non-linear regression programme for personal computer. Following intravenous administration of meloxicam, the values of elimination half life (t1/2_β), mean residence time (MRT), area under curve (AUC) and total body clearance (Cl_B) in buffalo calves were observed as 40.48 ± 1.94 h, 23.51 ± 0.18 h, 55.54 ± 5.41 μg h ml⁻¹ and 0.17 ± 0.00 ml min⁻¹ kg⁻¹, respectively. Similarly in sheep, the mean ±S.E. values of elimination half life (t1/2_β), Mean residence time (MRT), Area under curve (AUC) and Total body clearance (Cl_B) 6.50 ± 0.07 h,9.62 ± 0.12 h, 9.55 ± 0.21 μg h ml⁻¹ and 0.87 ± 0.02 ml min⁻¹ kg⁻ respectively. Significant differences were observed in all values of pharmacokinetic parameters between sheep and buffalo calves. Result of present study indicated that elimination kinetics of meloxicam differed significantly between sheep and buffalo calves, with relatively faster elimination in sheep as compared to buffalo calves. There is strong evidence of difference in pharmacokinetic behavior of meloxicam between sheep and buffalo calvesrequiring species specific dosage regimen.