DISPOSITION OF ENROFLOXACIN AND ITS METABOLITE CIPROFLOXACIN AFTER INTRAVASCULAR INJECTION IN JUVENILE BURMESE PYTHONS (PYTHON MOLURUS BIVITTATUS)

Eleven juvenile Burmese pythons (Python molurus bivittatus) weighing 0 .75-1.75 kg were randomly divided into two groups. Blood samples were obtained through surgically placed anterior carotid artery cannulas. S ix pythons received a single i.m. injection of enrofloxacin at 5 mg/kg . Blood samples were obtained at 0.5, 1, 3, 6, 12, 24, 48, 72, and 96 hr postinjection. A mean (+/-SD) maximal plasma concentration of 1.66 (+/-0.42) mu g/ml was measured at 5.75 hr postinjection. The harmonic mean half-life was calculated to be 6.37 hr. The second group of five snakes received enrofloxacin at 5 mg/kg i.m. s.i.d. for 5 days. Blood was collected immediately before each injection and at 6 hr after each injection. Over the 5-day period, there was a stepwise increase in me an trough plasma concentrations of enrofloxacin. Clinically effective peak plasma enrofloxacin concentrations were attained after the first injection but did not significantly increase during the sampling perio d. Pharmacokinetic data were assessed against minimum inhibitory conce ntrations of enrofloxacin for Pseudomonas spp. isolates in snakes obta ined from historical data at the Veterinary Medical Teaching Hospital, University of Florida. Enrofloxacin should be administered at 10 mg/k g i.m. every 48 hr when treating Pseudomonas spp. infections in juveni le Burmese pythons. Treatment of infections of more enrofloxacin-sensi tive gram-negative bacteria could be achieved with the administration of an initial i.m. dose of 10 mg/kg followed by 5 mg/kg every 48 hr.