Pharmacokinetics and oral bioavailability of ampicillin and its prodrug bacampicillin in chickens and turkeys.

Importance: Reports comparing the pharmacokinetics of ampicillin (AMP) and its prodrug bacampicillin (BAC) in poultry are scarce.

Objective: This study evaluated the pharmacokinetic characteristics of AMP and BAC in chickens and turkeys after intravenous (i.v.) or oral administrations at a single dosage of 25 mg/kg body weight.

Methods: Thirty chickens and 30 turkeys were divided into three groups (n = 10). Blood samples (0.5-0.7 mL) were collected from the subcutenea ulnar vein at pre-assigned times up to 12 h. The AMP and BAC plasma concentrations were analyzed using high-performance liquid chromatography with a fluorescence detector. The data were analyzed using noncompartmental methods.

Results: The area under the curve from 0 to 12 h, apparent total systemic, the apparent volume of distribution, and mean residence time differed significantly according to the administration routes. The terminal elimination half-life values for the i.v. AMP, oral AMP, and oral BAC routes were 1.81, 3.64, and 5.39 h (p = 0.0249, p < 0.05), respectively, in chickens, and 2.44, 2.53, and 5.5 h (p < 0.0001), respectively, in turkeys. The bioavailability for the oral AMP and oral BAC groups in chickens was 25.9% and 44.6%, respectively. Similarly, in turkeys, the bioavailability was 19.1% and 44.2% for the oral AMP and oral BAC groups, respectively.

Conclusions and relevance: The oral route of BAC with good bioavailability can be preferred for treating various conditions. On the other hand, further studies will be needed to determine the clinical efficacy of BAC during bacterial infections and the pharmacokinetics and safety of repeated administration in poultry.