Pharmacokinetics and penetration of danofloxacin from the blood into the milk of cows.
The single-dose disposition kinetics of danofloxacin were determined in clinically normal lactating cows after intravenous (i.v.) and intramuscular (i.m.) administration of the drug at 1.25 mg/kg. The drug concentrations in blood serum and milk were determined by microbiological assay methods and the data were subjected to kinetic analysis. The mean i.v. and i.m. elimination half-lives (t1/2el) in serum were 54.9 and 135.7 min, respectively. The steady-state volume of distribution (Vss) was 2.04 L/kg. The drug was quickly absorbed after i.m. injection but a 'flip flop' effect was clearly evident and bioavailability was > 100%. Penetration of danofloxacin from blood into milk was rapid and extensive with drug concentrations in milk exceeding those in serum beginning 90-120 min after i.v. and i.m. administration and onwards. Milk danofloxacin concentrations equal to or higher than the minimal inhibitory concentrations (MIC) for pathogenic Gram-negative bacteria and Mycoplasma species were maintained over approximately 24 h. Concentrations greater than the MIC for Staphylococcus aureus were maintained in the milk for 12 h.
Shem-Tov
M
M
Faculty of Agriculture, Hebrew University of Jerusalem, Rehovot, Israel.
Rav-Hon
O
O
Ziv
G
G
Lavi
E
E
Glickman
A
A
Saran
A
A
D000818:Animals; D000890:Anti-Infective Agents / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002417:Cattle; D004350:Drug Residues; D005260:Female; D024841:Fluoroquinolones; D006090:Gram-Negative Bacteria / Q000187:drug effects; D007273:Injections, Intramuscular / Q000662:veterinary; D007275:Injections, Intravenous / Q000662:veterinary; D007774:Lactation / Q000097:blood*; D008892:Milk / Q000737:chemistry*; D015363:Quinolones / Q000097:blood / Q000493:pharmacokinetics*; D013211:Staphylococcus aureus / Q000187:drug effects
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D015363:Quinolones; C068581:danofloxacin