实验性鸡大肠杆菌病病理学动态变化

用致病性大肠杆菌O18分离株和／或低致病性禽流感病毒（Mildly pathogenic avian influenza virus ,MPAIV)接种10－12日龄SPF鸡。在接种后1－96h进行临床症状与大体病理变化、组织学观察发现：大肠杆菌接种组、MPAIV接种组和健康接种组除扑杀鸡外未见鸡死亡，MPAIV与大肠杆菌混合接种组除扑杀鸡外死亡率为24％。混合接种组的病变比大肠杆菌接种组出现的时间早，恢复也慢，各脏器的病理变化更严重。MPAIV主要引起各实质器官的坏死，结果表明，大肠杆菌经气管内接种后试验鸡主要表现为呼吸道的炎症反应；MPAVI可使鸡大肠杆菌病严重化。

Pathologic Dynamics of Colibacillosis in Chickens Experimentally Inoculated with E.coli and/or Mildly Pathogenic Avian Influenza Virus

In order to study the pathogenesis of avian colibacillosis,10-day-old and 12-day-old SPF chickens were inoculated intracheally with virulent E.coli(O18)and/or mildly pathogenic avian influenza virus (MPAIV).Six chickens each were euthantized at different times from 1 to 96 h postinoculation and examined for macroscopic and microscopic lesions.Except euthantized chickens,in the groups that chickens inoculated with E.coli alone,or with MPAIV alone none of chickens died,meanwhile,24 percent mortality was observed in the chickens inoculated with MPAIV and E.coli.Chickens inoculated with MPAIV and E.coli had more severe and persistent lesions than those inoculated with E.coli or MPAIV alone.There were moderate inflammation in the serosa of the trachea,lung and air sac and scattered necrosis of parenchyma organs in chickens inoculated with MPAIV alone.These results suggest that MPAIV might facilitate E.coli invasion into the respiratory tract of the chicken resulting in severer avian colibacillosis.