Disposition of Ciprofloxacin in Red-Tailed Hawks (Buteo jamaicensis) following a Single Oral Dose

The disposition of ciprofloxacin following a single oral dose (50 mg/kg) was studied in 10 red-tailed hawks (Buteo jamaicensis). Blood samples were collected at 0, 15, 30, 45, 60, 90, 120, 180, 240, 360, 480, 600, and 720 min after dose administration. Based on a one-compartment model, the model-dependent pharmacokinetic determinants were 2.49 hr for the apparent elimination half-life, 3.64 ± 0.80 μg/ml for the peak concentration, 0.92 ± 0.26 hr for the time to peak, and a 0.18 ± 0.08-hr lag time. Model-independent determinants included an area under the curve of 16.6 ± 5.07 μg(hr)/ml, an area under the moment curve of 68.8 ± 27.6 μg(hr⁲)/ml, and a mean residence time of 4.06 ± 0.52 hr. Based on these data, a dose of 50 mg/kg given as an oral suspension every 12 hr would give serum concentrations above the published$\text{MIC}_{90}$for most bacteria susceptible to ciprofloxacin.