Pharmacokinetics of enrofloxacin in lactating sheep

Abstract

The pharmacokinetics of enrofloxacin (ENR) was investigated after its intravenous (iv) and intramuscular (im) administration in six healthy lactating sheep. After iv ENR injection (as a bolus), the elimination half-life ( t 1/2 β ), the volume of distribution ( Vd area), and the area under the concentration vs. time curve (AUC) were 3.30 (0.36) h, 2.91 (0.17) l/kg and 4.19 (0.18) μg h/ml, respectively. The maximum milk concentrations of ENR ( C max), the area under the milk concentration vs. time curve (AUC milk) and the ratio AUC milk/AUC serum were 2.38 (0.14) μg/ml, 23.76 (2.21) μg h/ml and 5.62 (0.30), respectively. After im administration of ENR the t 1/2 β , C max, time of C max ( t max) and absolute bioavailability ( F abs) were 3.87 (0.10) h, 0.74 (0.07) μg/ml, 0.83 (0.12) h and 75.35%, respectively. The C max, AUC milk and the ratio AUC milk/AUC serum were 1.94 (0.13) μg/ml, 24.81 (2.25) μg h/ml and 8.15 (0.96), respectively.