单诺沙星对鸡败血支原体与大肠杆菌合并感染的药效学研究

Pharmacodynamic Studies of Danofloxacin in Chicks Infected with Mycoplasma gallisepticum and E.coil

采用试管二倍稀释法测得单诺沙星及其对照药物恩诺沙星、泰乐菌素对鸡败血支原体( MG)的最低抑菌浓度分别为 0 .0 62 5、0 .1 2 5、0 .5mg/L。试验鸡每只左右气囊分别接种 MG S6株菌液 0 .75ml、滴鼻约 0 .3ml,同时腹腔注射大肠杆菌菌液 0 .3ml,人工诱发鸡败血支原体与大肠杆菌合并感染的疾病模型。 2 5、50、1 0 0 mg/L的单诺沙星、50 mg/L的恩诺沙星和 50 0 mg/L的泰乐菌素连续饮水 5d给药 ,对人工合并感染鸡败血支原体与大肠杆菌病的治愈率分别为 93.3%、96.6%、96.6%、93.3%、86.6% ,而感染对照组的死亡率为 2 3.3%。单诺沙星及其对照药物组的增重率显著高于感染对照组 ,并能极显著的降低感染鸡的死亡率、抗体反应阳性率。

Minimal inhibitory concentrations(MICs) of Danofloxacin,Enofloxacin and Tylosin against Mycoplasma gallisepticum were determined in vitro and proved to be 0.062 mg/L, 0.125mg/L and 0.5mg/L respectively.Chickens were infected with both Mycoplasma gallisepticum S6 and E.Coil,and treated via drinking water with Danofloxacin (25mg/L, 50mg/L, 100mg/L), Enofloxacin (50mg/L) and Tylosin(500mg/L) respectively for five consecutive days.Mean weight gains of the medicated were significantly higher than those of the unmedicated groups.23.3%,3.5%,0%,0%,3.3% and 6.6% of chickens in the medicated groups died respectively,while 23.3% the unmedicated controls died.It demonstrated that Danofloxacin was highly effective in reducing mortality and frequency of MG reisolation as well as in preventing seroconversion and air\|sac lesions in surviving birds.