不同地理株杂交培育的柔嫩艾美球虫及其免疫保护率

Development of Hybrid Strains from Geographic Isolates of Eimeria tenella and Their Immunoprotection

目的 培育 3个不同地理株柔嫩艾美球虫 (Eimeriatenella)的杂交株 ,以探讨研制球虫疫苗的可能性。 方法 通过免疫试验 ,从 5个不同地理株中选择 3株作为杂交亲本株 ,对此 3株分别进行两次杂交 ,获得的后代混合卵囊经单卵囊分离、扩增 ,分别提取卵囊DNA ,利用随机扩增多态性DNA(RAPD)进行分析 ( 3 0条引物 ) ,分离、培育出两代杂交株。再进行免疫试验 ,比较杂交株与亲本株的免疫保护性。 结果 选择了免疫原性较好、免疫保护率较高的广州株、保定株、长春株作为杂交亲本 ,分别进行保定株×长春株、广州株×F1株两次杂交 ,获得的后代卵囊 ,提取卵囊DNA ,RAPD分析后 ,得到了保定株×长春株的杂交株F1(F1Z7)和广州株×F1株的杂交株F2 (F2Z3 )。免疫试验结果 ,杂交株F1与F2的免疫保护率分别为 80 %和 84% ;亲本株广州株为 77% ,保定株为 69% ,长春株为 63 %。 结论 分离、培育出了F1、F2两代杂交虫株。其免疫保护率均高于各亲本株 ,提示杂交株获得了亲本株的部分保护性 ,其免疫的雏鸡对各虫株的攻击均有好的保护力。尤其是F2株 ,免疫保护率平均达到 84%

Objective To cultivate hybrid strains from three geographic isolates of Eimeria tenella and to explore the possibility of developing vaccine candidates. MethodsThree parental strains were selected from five geographic isolates of E.tenella through immune experiment, and hybrid strains were cultivated. The genomic DNA of the three parental strains and their filial generation were analyzed by random amplified polymorphic DNA(RAPD) technique with 30 optimization primers screened from 200 primers, the hybrid strains were isolated from the filial generation by RAPD. Chicken were inoculated with hybrid strains, and challenged with different strains to compare the immunogenicity and immunoprotection. Results Immunogenicity and immunoprotecion of the three strains isolated from Guangzhou, Baoding and Changchun were stronger than those of other strains. Hybridization was performed to cultivate hybrid strain. Two hybrid strains were isolated from Changchun×Baoding and Guangzhou×F1 by RAPD. The result of immune experiment proved that immunoprotecion of F1 and F2 were higher than their parental strains. Conclusion Two hybrid strains have been cultivated from the three geographic isolates of E.tenella, with the immunogenicity of their parental strains. Chicken immunized by F2 strain have shown strong resistance against the infection of the geographic strains, with an average protection rate of 84%.