摘要
对巨型艾美耳球虫(长春株)经20代的早熟选育,其潜隐期由132h缩短到116h,成为早熟株.该早熟株不经选择传递2代,仍保持了早熟的特性.该早熟株比其亲代株繁殖力下降74%,致病力降低,但仍然保持了其免疫原性.
By 20 generations of serial selection for precociousness, a strain of E. maxima with a prepatent ttme of 116 hours was obtained. This Strain retained its precociousness after 2 passages without selection pressure. Its reproductive potential was lowered and pathogenicity reduced , whereas its immunogenicity was retained.
关键词
艾美耳球虫
早熟株
减毒株
选育
chick
Eimeria maxima
precocious strain
attenuation
coccidial vaccine
