RAPD技术在鸡球虫虫株鉴定上的应用

Study of Differentiation of Eimeria Intra-species by the Random Amplification of Polymorphic DNA

采用 RAPD 技术对 E.tenella 早熟株、鸡胚株、亲本毒抹和田间分离的抗药株进行研究,发现本研究选育的 E.tenella 早熟株与亲本毒株间 DNA 多态性存在着差异,证实该早熟侏已发生了遗传变异,但变异程度不大;而鸡胚株及抗药株却比早熟株的变异程度大。建议 RAPD 技术可用于艾美耳球虫株间差异及其球虫株间关系距离的检测.对经细胞培养的 E.acervulina 早熟株及其毒株和抗药株的基因组 DNA 进行多态性比较研究,发现该3株球虫间的变异程度大于 E.tenella 各虫株间的变异,即不同来源的 E.ac-ervulina 各虫株间的相似性小于 E.tenella 各虫株间的相似性,表明不同球虫其种内变异程度不一致。本研究结果表明 RAPD 技术可作为球虫株间变异的分子标记方法及其球虫株间关系距离的检测手段。

The genomie DNA of the precocious strain,parental strain,embryo-adapted strain,the drug-resistant strain of E.tenella and the precocious strain,the virulent strain and the drug-resistant strain of E.acervulina were analysed by RAPD.Genomic finger- prints generated by RAPD revealed a high degree of similarity(SI)between the strains of E.tenella and the strains of E.acervulina.The results showed that the similarity(SI= 0.895 0-0.983 6)between E.tenella strains was higher than that(SI=0.800 0-0.859 2)between E.acervulina strains.It was suggested that the intra-specific variance between the strains of different virulence,geography,drug-resistant was not consistent.The re- sults of this study demonstrated that the strain-specific fragment of Eimeria strains can be amplified by the RAPD technique,and the RAPD method may be an extremely useful tool for studies on the genetic organisation of coccidial parasites.Polymorphisms detected by RAPD-PCR might facilitate the selection of molecular markers and study of the relation- ship between different strains.