为选育制备弱毒疫苗所需的毒害艾美耳球虫早熟株, 运用Jeffers建立的早熟系选育方法对毒害艾美耳球虫(E.necatrix)山西分离株进行了早熟选育, 并观察其内生发育。结果表明, 经过海兰白雏鸡8次传代之后, E.necatrix潜隐期由146.5 h缩短至139 h, 排卵高峰期由168 h提前至156 h; 其虫体各个发育阶段与亲本株相似, 但第二代裂殖体明显小于亲本株, 且出现的高峰提前。

In order to select the Precocious strain of the E.necatrix for developing the anti-chicken coccidiosis precocious attenuation vaccine,a precocious strain of the E.necatrix in shanxi province was selected as Jeffers, further observed the endogenous stage. The results showed that the prepatent period of the precocious line was shortened from 146.5 h to 139 h, the peak time of the oocysts was ahead from 168 h to 156 h by repeated 8 passages of oocysts that were collected from the faces of previously infected chickens;The endogenous developmental stages of the a precocious strain was similar to that of the parental strain,but the 2nd generation of schizonts was obviously smaller than that of the parental strain,and the peak time was ahead.