Pharmacokinetic study of danofloxacin in cattle and swine

Pharmacokinetic values of a new quinolone antimicrobial, danofloxacin, were studied in cattle and swine. Plasma concentration was detected within 15 minutes after IM administration, peaked by 1 hour, and subsequently decreased, with half-life of 2.9 and 6.8 hours for cattle and swine, respectively. In swine, danofloxacin was absorbed, whether orally administered by gavage, in feed, or in drinking water. Danofloxacin concentrated in lung tissue at 4 to 7 times the plasma concentration. Lung tissue concentration exceeded the minimal inhibitory concentrations for im90portant respiratory tract pathogens for extended periods after administration of the drug by any of the routes studied. The major routes of excretion were in urine and bile.