pure-culture maintenance

• 保持纯种

pure-culture maintenance的用法和样例：

例句

1. The parents of this puppy are pure breeds.
   这只小狗的父母都是纯种犬。
2. Breeders of thoroughbred animals perpetuate genetic disorders to keep pedigrees pure.
   纯种家畜的养育者们为了保持纯正的动物血统无休止地制造遗传上的混乱现象。