Pharmacokinetics of Ceftazidime in Koi (Cyprinus carpio) After Single Dose Intramuscular or Intracoelomic Administration
Pamela D. Govett1,2,3; Jennifer Buur1; Avery Krein1; Terry McDowell4; E. Scott Weber, III4
1Western University, College of Veterinary Medicine, Pomona, CA, USA; 2Environmental Medicine Consortium, North Carolina State University, College of Veterinary Medicine, Raleigh, NC, USA; 3California Science Center, Los Angeles, CA, USA; 4University of California, Davis, College of Veterinary Medicine, Davis, CA, USA
Ceftazidime pharmacokinetics were studied in adult koi (Cyprinus carpio) following single intramuscular (i.m.) and intracoelomic (i.ce.) injections. Twenty-two koi were divided into two groups. Eleven animals received 20 mg/kg ceftazidime i.m. and eleven received the same dose i.ce. Plasma ceftazidime concentrations were analyzed at predetermined intervals by reverse-phase high performance liquid chromatography. In the preliminary study, the Cmax was 41 µg/ml and the peak was seen at 12 hours post-i.m.-injection. The i.ce. administration demonstrated pharmacokinetics consistent with flip-flop kinetics and reached substantially lower peak plasma concentrations than the i.m. injection around 7 µg/ml. The i.m. concentration was above the minimum inhibitory concentration (MIC) values for Aeromonas hydrophilia and Renibacterium salmoninarum indicating that 20 mg/kg i.m. produces serum ceftazidime concentrations that are within a therapeutic range for koi.