Some pharmacokinetic data for danofloxacin in healthy goats

The pharmacokinetics of danofloxacin was determined in five clinically normal 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 animal at precise time intervals. Serum and urine concentrations were determined using microbiological assay methods and the data were subjected to kinetic analysis. After intravenous injection, the serum concentration-time curves of danofloxacin were characteristic of a two-compartment open model. The 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 central, 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 after 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 protein-bound fraction was 13.55 +/- 1.78%.