Pharmacokinetics and bioavailability of meloxicam in Pekin ducks following intravenous, intramuscular and oral administration

Objective To determine the pharmacokinetics and bioavailability of meloxicam following intravenous (IV), intramuscular (IM), and oral administrations at a dose of 1.0 mg kg–1 in Pekin ducks. Study design Randomized experimental trial. Animals A total of 18 clinically healthy male Pekin ducks. Methods Pekin ducks were randomly assigned to three groups of six ducks: IV, IM and oral. Meloxicam (1.0 mg kg–1) was administered to each Pekin duck. A non-compartmental analysis was used to evaluate pharmacokinetic parameters. Results No local or systemic adverse effects were observed in any bird. Meloxicam was detected in the plasma up to 120 hours following IV, IM or oral administration. The elimination half-life of the IV route was slightly shorter than that of the IM and oral routes (p < 0.05). Following IV administration, volume of distribution at steady state and total clearance were 133.17 mL kg–1 and 6.68 mL kg–1 hour–1, respectively. The mean absorption time was 2.29 hours for IM and 1.13 hours for oral route. There were significant differences between IM and oral administration for the peak plasma concentration (Cmax), time to reach Cmax and bioavailability (p < 0.05). Conclusions and clinical relevance Meloxicam showed long elimination half-life and high bioavailability following IM and oral administration. Meloxicam in Pekin ducks provided the effective therapeutic concentration indicated in other species for up to 48 hours. However, there is a need to determine the clinical efficacy of meloxicam in Pekin ducks.