Poapolathep Saranya, Giorgi Mario, Chaiyabutr Narongsak, Klangkaew Narumol, Phaochoosak Napasorn, Wongwaipairote Tara, Poapolathep Amnart
Department of Pharmacology, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, Thailand.
Department of Veterinary Sciences, University of Pisa, San Piero a Grado, Italy.
J Vet Pharmacol Ther. 2020 Mar;43(2):141-146. doi: 10.1111/jvp.12801. Epub 2019 Jul 29.
One of the major obstacles to the successful treatment of infectious disease in freshwater crocodile species is incorrect dosing of antibiotics. There are few reports on pharmacokinetics and dosage regimens of antimicrobial drugs in crocodiles. The purpose of the present study was to clarify the pharmacokinetic characteristics of ceftriaxone (CEF) in Siamese freshwater crocodiles (Crocodylus siamensis). Freshwater crocodiles, Crocodylus siamensis, in breeding farms were treated with a single intramuscular administration of CEF at two dosages, 12.5 and 25 mg/kg body weight (b.w.). Blood samples were collected at preassigned times up to 168 hr. The plasma concentrations of CEF were measured by a validated method through liquid chromatography tandem-mass spectrometry. CEF plasma concentrations were quantified up to 72 and 96 hr after low- and high-dose administration, respectively. The C values of CEF were 24.61 ± 5.15 µg/ml and 26.39 ± 2.81 µg/ml at dosages of 12.5 and 25 mg/kg b.w., respectively. The AUC values increased in a dose-dependent fashion. The half-life values were not statistically different between the groups (around 20 hr). The average binding percentage of CEF to plasma protein was 53.78 ± 2.11%. Based on the pharmacokinetic data, susceptibility break-point and the surrogate PK-PD index (T > MIC, 0.2 μg/ml), i.m. administration of CEF at a dose of 12.5 mg/kg b.w. might be appropriate for initiating treatment of susceptible bacterial infections in freshwater crocodiles.
淡水鳄鱼物种传染病成功治疗的主要障碍之一是抗生素剂量不正确。关于鳄鱼抗菌药物的药代动力学和给药方案的报道很少。本研究的目的是阐明头孢曲松（CEF）在暹罗淡水鳄鱼（Crocodylus siamensis）中的药代动力学特征。对养殖场中的暹罗淡水鳄鱼（Crocodylus siamensis）以12.5和25mg/kg体重（b.w.）两种剂量进行单次肌肉注射CEF治疗。在预先设定的时间点采集血样，最长至168小时。通过液相色谱串联质谱法的验证方法测量CEF的血浆浓度。低剂量和高剂量给药后，CEF血浆浓度分别在72小时和96小时内进行定量。CEF在12.5和25mg/kg b.w.剂量下的C值分别为24.61±5.15μg/ml和26.39±2.81μg/ml。AUC值呈剂量依赖性增加。两组之间的半衰期值无统计学差异（约20小时）。CEF与血浆蛋白的平均结合百分比为53.78±2.11%。根据药代动力学数据、药敏折点和替代PK-PD指数（T>MIC，0.2μg/ml），以12.5mg/kg b.w.的剂量肌肉注射CEF可能适合开始治疗淡水鳄鱼的易感细菌感染。
