鸡毒害艾美尔球虫早熟株的免疫原性研究

为制备早熟弱毒疫苗提供虫株和理论依据,对选育的毒害艾美尔球虫早熟株(P8)和亲本株(P0)的免疫原性进行了研究。试验分别用P0和P8,以每只鸡300个孢子化卵囊免疫7日龄雏鸡,免疫后14 d,分别以每只鸡1×104和10×104个P0孢子化的卵囊进行攻毒,以OPG、平均每只鸡的卵囊产量,卵囊减少率、相对增重率、病变记分减少率为指标。结果表明:(1)攻毒后每只1×104个P0孢子化的卵囊时,P8、P0免疫攻毒组的卵囊减少率分别为75.59%、84.66%;(2)攻毒后每只10×104个P0孢子化的卵囊时,P8、P0免疫攻毒组病变记分降低率分别为81.46%、76.66%。表明P8株的免疫原性与P0无明显变化,均有保护力,符合早熟株免疫原性保持不变的特点。

The Immunogenicity of the Precocious line of Eimeria necatrix

In order to provide the strain and theoretical foundation of preparing attenuation vaccine,the immunogenicity of precocious(P8) and parental(P0) E.necatirx strain were studied.P0 and P8 were inoculated to the 7-day-old chickens both at a dosage of 300 sporutated oocysts per chicken,then 1×104 and 10×104 sporutated oocysts of P0 were inoculated 14 days after post-immunization.The oocysts per gram(OPG),oocyst production of per chicken,reduction of oocyst,relative weight gain rate and reduction of lesion score were tested as index.The result indicated that:(1) the reduction of oocyst of the immunity group P8 and P0 were 75.59% and 84.66% respectively when inoculated 1×104 oocysts per chicken.(2) the reduction of lesion score of the immunity group P8 and P0 were 81.46% and 76.66% respectively when inoculated 10×104 oocysts per chicken.The result shows that the immunogenicity of P0 and P8 which both provide protection has no significant change,and it is corresponded to the character of keeping invariant of precocious strain immunogenicity.