Meegan Jenny, Collard Wendy T, Grover G Scott, Pussini Nicola, Van Bonn William G, Gulland Frances M D
University of Florida College of Veterinary Medicine, P.O. Box 100136, Gainesville, Florida 32610, USA.
J Zoo Wildl Med. 2013 Sep;44(3):714-20. doi: 10.1638/2013-0001R.1.
The pharmacokinetics of ceftiofur crystalline-free acid (EXCEDE Sterile Suspension, 200 mg ceftiofur equivalents/ml) were determined for the California sea lion (Zalophus californianus). A single dose of EXCEDE was administered intramuscularly at 6.6 mg/kg to 12 wild California sea lions during rehabilitation. The first 10 animals were each assigned to two blood collection time points, with a total of 10 time points at: 6, 12, 24, 48, 72, 96, 120, 144, 168, and 192 hr after administration of the drug. An additional two animals were sampled 1, 2, 3, 4, 5, and 6 hr postinjection. Plasma was separated within 10 min of blood collection and stored at -20 degrees C until analysis. Plasma concentrations of ceftiofur, desfuroylceftiofur, and related metabolites, were determined using liquid chromatography with tandem mass spectrometry (MS). Maximum plasma concentrations of ceftiofur and related metabolites were observed 24 hr postdosing with a mean concentration of 3.6 microg/ml. The half life (60 hr) and area under the curve (270 microg x hr/ml) were also determined. These data indicate that a single dose of EXCEDE at 6.6 mg/kg i.m. would likely maintain a mean plasma drug level >0.6 microg/ml for 5 days and >0.5 microg/ml for 8 days.
测定了头孢噻呋晶体游离酸（EXCEDE无菌混悬液，200mg头孢噻呋等效物/毫升）在加利福尼亚海狮（北海狮）体内的药代动力学。在康复期间，对12只野生加利福尼亚海狮以6.6mg/kg的剂量肌肉注射单剂量的EXCEDE。前10只动物分别被分配到两个采血时间点，给药后共有10个时间点：6、12、24、48、72、96、120、144、168和192小时。另外两只动物在注射后1、2、3、4、5和6小时进行采样。在采血后10分钟内分离血浆，并在-20℃下保存直至分析。使用液相色谱-串联质谱法（MS）测定血浆中头孢噻呋、去呋喃甲酰头孢噻呋及相关代谢物的浓度。给药后24小时观察到头孢噻呋及相关代谢物的血浆浓度最高，平均浓度为3.6μg/ml。还测定了半衰期（60小时）和曲线下面积（270μg·小时/ml）。这些数据表明，以6.6mg/kg的剂量肌肉注射单剂量的EXCEDE可能会使血浆药物平均水平在5天内>0.6μg/ml，在8天内>0.5μg/ml。
