Pharmacokinetics of extended-release lipid buprenorphine in Hispaniolan Amazon parrots (Amazona ventralis) and its effects on body temperature.

Abstract

Objective: To obtain pharmacokinetic (PK) parameters of a single dose of extended-release lipid buprenorphine (ER-B; 2 mg/kg SC) and evaluate its effects on body temperature (BT) in Hispaniolan Amazon parrots (Amazona ventralis) (HAPs).

Methods: In this experimental PK study, ER-B was administered to laboratory-housed HAPs, and BT was measured using SC transponders. One week before the PK study, BT was measured at 0.25, 1, 2, 3, 6, 12, 24, 48, and 72 hours, so each bird could serve as their control (CTRL). A single dose of ER-B was administered, and blood collection and BT were obtained at the same time points over 72 hours. Signs of sedation or adverse effects were recorded. A PK analysis was performed. Statistical analysis for BT of the CTRL and ER-B groups was performed. An ANOVA with a mixed-effect model and a post hoc Tukey comparison was used.

Results: A PK profile from 15 parrots was obtained. Extended-release lipid buprenorphine was rapidly absorbed, with a mean time to maximum plasma concentration of 2.1 hours and a mean half-life of 13.8 hours. The ER-B plasma concentration was > 1 ng/mL for > 48 hours. Body temperature significantly decreased at 3 hours (ER-B, 39.7 ± 0.3 °C; CTRL, 40.7 ± 0.3 °C; mean difference, -1.06 °C; 95% CI, -1.97 to -0.1) and 6 hours (ER-B, 39.7 ± 0.3 °C; CTRL, 40.9 ± 0.3 °C; mean difference, -1.2 °C; 95% CI, -2.16 to -0.3) postadministration.

Conclusions: Extended-release lipid buprenorphine in HAPs sustains plasma concentrations for > 48 hours, with mild sedation. Body temperature decreased at 3 and 6 hours postadministration.

Clinical relevance: Extended-release lipid buprenorphine in HAPs has a prolonged plasma concentration and reduced BT postadministration. Further pharmacodynamic evaluation could be warranted.