Single and multiple oral amoxicillin treatment in geese: a pharmacokinetic evaluation.

1. Although amoxicillin has broad-spectrum antibiotic activity and is extensively used in poultry, its use has never been investigated in geese. This study aimed to evaluate the pharmacokinetics of amoxicillin after a single and multiple oral doses in geese.2. A total of 20 geese were enrolled in this study and randomly pooled in two groups ( = 10). In group I, animals were treated with a single oral 20 mg/kg dose of amoxicillin, while geese in group II were administered multiple doses (20 mg/kg/day for 4 d). Concentrations of amoxicillin in plasma were analysed using a validated HPLC-UV method and drug plasma concentrations were modelled for each subject using a non-compartmental approach.3. amoxicillin showed rapid absorption after a single-dose treatment, with an elimination half-life of approximately 1 h. C, T and AUC values differed statistically between groups I and II (after the first dose administered). A large variability was observed in the pharmacokinetic profiles and drug accumulation may occur after the multiple administration.4. No accumulation in plasma was predicted from an simulation performed using the same multiple dosage schedule. The simulation does not seem to accurately predict in-field conditions.