Population Pharmacokinetics of Danofloxacin After Single Intramuscular Dose Administration in California Brown Pelicans (Pelecanus occidentalis californicus)

• Published in: Journal of avian medicine and surgery Vol. 33; no. 4; pp. 361 - 368
• Main Authors: Schmitt, Todd L, Nollens, Hendrik H, Simeone, Claire A, Papich, Mark G
• Format: Journal Article
• Language: English
• Published: United States Association of Avian Veterinarians 09.12.2019
• Subjects: Analysis; Animals; Anti-Infective Agents - administration & dosage; Anti-Infective Agents - blood; Anti-Infective Agents - pharmacokinetics; Area Under Curve; avian; bacteria; Beef cattle; birds; Birds - metabolism; Body weight; Brown pelican; California; Chromatography; Chromatography, High Pressure Liquid - veterinary; danofloxacin; drugs; Fluoroquinolones - administration & dosage; Fluoroquinolones - blood; Fluoroquinolones - pharmacokinetics; Half-Life; High performance liquid chromatography; Injections, Intramuscular - veterinary; Instrument industry (Equipment); Intramuscular Absorption; intramuscular injection; Liquid chromatography; Microbial Sensitivity Tests - veterinary; minimum inhibitory concentration; Nonlinear Dynamics; ORIGINAL STUDIES; Original Study; Pectoralis Muscles - metabolism; Pelecanus occidentalis; Pelecanus occidentalis californicus; Pelicans; pharmacokinetics; therapeutics; United States; California; pharmacokinetics; brown pelican; danofloxacin; Pelecanus occidentalis californicus; avian
• ISSN: 1082-6742; 1938-2871
• DOI: 10.1647/2018-366

The pharmacokinetics of danofloxacin was investigated in rehabilitated California brown pelicans (Pelecanus occidentalis californicus) after a single intramuscular injection at a dose of 15 mg/kg body weight. The concentration of the drug in plasma was assayed by high-pressure liquid chromatography. A sparse-sampling design was used to reduce the number of samples (1–4 venipunctures) obtained from 24 brown pelicans. A population pharmacokinetic analysis with nonlinear mixed-effects modeling was used to accommodate the sparse-sampling strategy. The nonlinear mixed-effects modeling approach measured both fixed effects (typical values for the population) and random effects (between-subject variability) for this population. A 1-compartment model best represented the concentration-versus-time data after injection. After injection, the elimination half-life, peak concentration, area under the curve, and volume of distribution were 2.76 hours, 2.5 µg/mL, 13.75 µg/h/mL, and 4.35 L/kg, respectively. Rate of absorption was highly variable among the birds. The intramuscular injection of danofloxacin in pelicans at this dose produced plasma concentrations that meet therapeutic targets for bacteria with a minimum inhibitory concentration of ≤0.25 µg/mL. This dose can be used for future studies to evaluate the efficacy of danofloxacin for treating susceptible bacteria.