头孢噻呋钠对1日龄雏鸡实验性感染鸡大肠杆菌病的药效试验

Preventive Efficacy of Ceftiofur sodium on Experimental Escherichia coli. Infection in Day-old Chicks

通过预先颈部皮下注射头孢噻呋钠,评价其对1日龄雏鸡试验性诱导大肠杆菌病的预防效果。以微量法测得头孢噻呋钠和恩诺沙星对鸡大肠杆菌的MIC分别为0.1mg/L和1.6mg/L。试验结果表明,0.2、0.1、0.05mg/只的头孢噻呋钠各用药组对人工诱导鸡大肠杆菌病的保护率分别为100%、90%和80%,与0.125mg/只的恩诺沙星对照组(63.33%)及感染对照组(46.67%)相比,头孢噻呋钠各剂量组均能显著降低1日龄雏鸡人工诱发大肠杆菌病的死亡率(P<0.01),具有很好的预防效果;试验结束后细菌学检测结果表明,头孢噻呋钠各剂量组和药物对照组鸡的大肠杆菌检出率分别为13.33%、23.33%、30.0%、46.67%,与感染对照组(90%)相比均显著减少(P<0.01)。

The preventive effects of ceftiofur sodium on an experimentally induced colibacillosis in day-old chicks were evaluated by single subcutaneous injection prior to the inoculation of E.coli.The minimal inhibitory concentrations(MICs)of ceftiofur and enrofloxacin against E.coli(O 18 )were determined by microdilution method,the MIC of ceftio-fur and enrofloxacin were0.1mg/L?1.6mg/L,respectively.The in vivo test showed that ceftiofur sodium given re-spectively at the dose of0.2?0.1?0.05mg per chick exhibited significantly protective effects on chicks infected with E.coli.,the protective rates were100%,90%and80%,respectively,which was superior to enrofloxacin(63.33%),and the infected control group.All groups treated with drug significantly reduced frequency of E.coli.reisolation.