鸡毒支原体SC克隆致弱株免疫原性测试——开放动物模型的建立与应用

Detection of the Immunogenicity of MG Attenuated S6 Strain:a Model with the Stress of Pathogenic E.coli

对罗斯鸡和 Ｓ Ｐ Ｆ来航鸡用鸡毒支原体强毒攻击时，以鸡致病性大肠杆菌 Ｏ７ ８ 血清型菌株 １６ 小时培养物 ０２ｍ ｌ／羽皮下注射作人工诱导发病，试验鸡出现明显气囊病变，初步建立了以鸡致病性大肠杆菌为诱导因子的 Ｍ Ｇ 野外环境人工发病的动物模型。以此开放模型检测 Ｓ Ｐ Ｆ来航鸡以鸡毒支原体 Ｓ６ 克隆致弱株 Ｆ１５６ 代培养物点眼、滴鼻免疫后 ３０ 日、６０ 日龄的攻毒保护率，结果保护率分别达 ９０％ （１８／２０）、８４％ （４２／５０），而对照组为 ３０％ （６／２０）、５０％ （１５／３０），中期免疫效果证明，鸡毒支原体 Ｓ６ 克隆致弱株有良好的免疫保护作用。

Field Ross and SPF Lahore chickens present apparent air sac lesions when challenged with MG isolated strains,together with the injection subcutaneous of 0.2ml 16h cultures of avian pathogenic Escherichia coli (E.coli).In this model,the immunogenicity of attenuated MG S6 F156 was test,and the results showed 90%(18/20)chickens at 30 days and 84%(42/50)chickens at 60 days were free of air sac lesions after inoculated while the control were 30%(6/20) and 50%(15/32)respectively.Apparent protection effect against the MG challenge with inoculation of MG S6 F156 were present 30 and 60 days,Whether it can be possible alternatives to a live vaccine remained to be tested.