The study aims to describe the pharmacokinetics of doxycycline after a single intravenous and oral dose (20 mg/kg) in geese. In addition, two multiple-dose simulations have been performed to investigate the predicted plasma concentration after either a 10 or 20 mg/kg daily administration repeated consecutively for 5 days. Ten geese were enrolled in a two-phase cross-over study with a washout period of two weeks. All animals were treated intravenously and orally with doxycycline, and blood samples were collected up to 48 h after drug administration. Sample analysis was performed using a validated HPLC-UV method. A non-compartmental approach was used to evaluate the pharmacokinetic parameters of the drug. A long elimination half-life was observed (13 h). The area under the curve was statistically different between the two treatments, with the oral bioavailability being moderate (43%). The pharmacokinetic/pharmacodynamic index (%T>MIC) during the 48 h treatment period in the present study (71%) suggests that doxycycline appears to have therapeutic efficacy against some Mycoplasma species in the goose. The multiple-dose simulations showed a low accumulation index. A dosage of 10 mg/kg/day for 5 days seemed to be adequate for a good therapeutic efficacy without reaching unnecessarily high plasma concentrations.

中文翻译：

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多西环素在鹅体内的药代动力学

该研究旨在描述多西环素在鹅中单次静脉内和口服剂量（20 mg/kg）后的药代动力学。此外，已经进行了两次多剂量模拟，以研究在每天 10 或 20 mg/kg 连续重复给药 5 天后的预测血浆浓度。十只鹅参加了一项为期两周的两阶段交叉研究。用强力霉素静脉内和口服所有动物，并在给药后48小时收集血样。使用经过验证的 HPLC-UV 方法进行样品分析。使用非隔室方法来评估药物的药代动力学参数。观察到较长的消除半衰期（13 小时）。两种处理的曲线下面积有统计学差异，口服生物利用度中等（43%）。本研究中 48 小时治疗期间的药代动力学/药效学指数 (%T>MIC) (71%) 表明多西环素似乎对鹅中的某些支原体物种具有治疗效果。多剂量模拟显示低累积指数。5 天 10 mg/kg/天的剂量似乎足以获得良好的治疗效果，而不会达到不必要的高血浆浓度。