中文摘要：

【目的】为兽医临床合理用药，进行头孢喹肟对金黄色葡萄球菌的最低抑菌浓度（ MIC）和防突变浓度（ MPC）研究．【方法】采用标准琼脂二倍稀释法，测定头孢喹肟对金黄色葡萄球菌的MIC和MIC99（抑制99％接种细菌生长的最低抑菌浓度）；使用肉汤法富集1010 CFU/mL金黄色葡萄球菌ATCC 29213和37株金黄色葡萄球菌临床分离菌，采用标准琼脂平板稀释法测定头孢喹肟对金黄色葡萄球菌的MPC，并计算选择指数（SI）．【结果和结论】头孢喹肟对金黄色葡萄球菌ATCC 29213的MIC和MIC99分别是0.5和0.4μg/mL， MPC为1.6μg/mL， SI （ MPC/MIC99）为4．头孢喹肟对37株临床分离的金黄色葡萄球菌的MIC50、MIC90和MPC90分别是0.50、1.00和5.12μg/mL；SI （ MPC90/MIC90）为5.12．头孢喹肟对金黄色葡萄球菌具有较强的抗菌活性，SI也较小，通过调整给药方案可以减少耐药突变株的产生．

英文摘要：

Objective] The minimal inhibitory concentration （ MIC） and the mutant prevention concentra-tion （ MPC） of cefquinome against Staphylococcus aureus were measured for the rational use in veterinary medicine .[Method] The MIC and MIC for 99%of input cells （ MIC99 ） of cefquinome against S.aureus were determined by agar two-fold dilution method .The S.aureus strains were enriched in broth , and the bacterial concentrations were adjusted to 1010 colony forming units （ CFU） per milliliter.The MPC of cefquinome against S.aureus was determined by agar plates dilution method , and the selection index （SI） was calculated.[Result and conclusion] The MIC, MIC99, MPC and SI （MPC/MIC99） of cefqui-nome against S.aureus strain ATCC 29213 were 0.5, 0.4 , 1.6 μg/mL and 4, respectively.The MIC50 , MIC90 , MPC90 and SI （ MPC90/MIC90 ） of cefquinome against S.aureus clinical isolates were 0.50, 1.00, 5.12μg/mL and 5.12, respectively .The results show that cefquinome has a higher activity against S.aureus and a smaller SI .Resistant mutant strains can be reduced by adjusting the dosage regimen .