The pharmacokinetics of danofloxacin was determined in five clinically norm
al adult female goats after intravenous (IV) or intramuscular (IM) doses of
1.25 mg/kg body weight. Blood and urine samples were collected from each a
nimal at precise time intervals. Serum and urine concentrations were determ
ined using microbiological assay methods and the data were subjected to kin
etic analysis. After intravenous injection, the serum concentration-time cu
rves of danofloxacin were characteristic of a two-compartment open model. T
he drug was rapidly distributed and eliminated with half-lives of 17.71 +/-
1.38 min and 81.18 +/- 3.70 min, respectively. The drug persisted in the c
entral, highly perfused organs with a K-12/K-21 ratio of 0.67 +/- 0.25. The
mean volume of distribution at a steady state (V-dss) was 1.42 +/- 0.15 L/
kg. After intramuscular administration, the serum concentration peaked afte
r 0.58 +/- 0.04 h at approximately 0.33 +/- 0.01 mug/ml. While danofloxacin
could be detected in serum for 4 and 6 h, it was recovered in urine for up
to 24 and 72 h after IV and IM administration, respectively. The systemic
bioavailability after IM injection was 65.70% +/- 10.28% and the serum prot
ein-bound fraction was 13.55 +/- 1.78%.