Pharmacokinetics of enrofloxacin in turkeys

Abstract

The pharmacokinetics of enrofloxacin (EFL) and its active metabolite ciprofloxacin (CIP) was investigated in 7–8 month old turkeys (6 birds per sex). EFL was administered intravenously ( i.v.) and orally ( p.o.) at a dose 10 mg kg −1 body weight. Blood was taken prior to and at 0.17, 0.33, 0.5, 1, 2, 3, 4, 6, 8, 10 and 24 h following drug administration. The concentrations of EFL and CIP in blood serum were determined by high-performance liquid chromatography (HPLC). Serum concentrations versus time were analysed by a noncompartmental analysis. The elimination half-live and the mean residence time of EFL after i.v. injection for the serum were after oral administration 6.64 ± 0.90 h, 8.96 ± 1.18 h and 6.92 ± 0.97 h, 11.91 ± 1.87 h, respectively. After single p.o. administration, EFL was absorbed slowly (MAT = 2.76 ± 0.48 h) with time to reach maximum serum concentrations of 6.33 ± 2.54 h. Maximum serum concentrations was 1.23 ± 0.30 μg mL −1. Oral bioavailability for for EFL after oral administration was found to be 69.20 ± 1.49%. The ratios C max/MIC and AUC 0→24/MIC were respectively from 161.23 ± 5.9 h to 12.90 ± 0.5 h for the pharmacodynamic predictor C max/MIC, and from 2153.44 ± 66.6 h to 137.82 ± 4.27 h for AUC 0→24/MIC, for the different clinically significant microorganisms, whose values for MIC varies from 0.008 μg L −1 to 0.125 μg mL −1.