A population approach was used to evaluate the pharmacokinetic parameters of 3
fluoroquinolones administered to Japanese quail (Coturnix coturnix japonica). Healthy adult quail (n = 50) were divided into 3 groups, each administered a separate intravenous and oral dose of the compounded
drug:
enrofloxacin at 10 mg/kg (n = 18; 9 male, 9 female),
danofloxacin at 10 mg/kg (n = 12; 6 male, 6 female), and
marbofloxacin at 5 mg/kg (n = 20; 10 male, 10 female). A fourth group was used as a control (n = 5).
Enrofloxacin was metabolized extensively to
ciprofloxacin, while no metabolites of either
danofloxacin or
marbofloxacin were detected. The volume of distribution was high, greater than 1 in all cases, and highest for
danofloxacin, followed by
enrofloxacin, then
marbofloxacin. The total body clearance was higher in quail than that reported for other avian species with the exception of ostriches. As in mammals, the lowest clearance rate of the 3
fluoroquinolones was observed for
marbofloxacin.
Enrofloxacin was absorbed most rapidly, followed by
marbofloxacin, then
danofloxacin. The highest bioavailability was observed for
danofloxacin followed by
marbofloxacin, while very low bioavailability with significant conversion to
ciprofloxacin was observed for
enrofloxacin. Population analysis showed low intersubject variability for
danofloxacin and
marbofloxacin in contrast to that for
enrofloxacin and its main metabolite,
ciprofloxacin. Because of their more favorable pharmacokinetic properties after
oral administration, either
danofloxacin or
marbofloxacin appears to be preferable to
enrofloxacin for the treatment of susceptible
bacterial infection in Japanese quail.