| 释义 |
〔grade〕To improve the quality of (livestock) by crossbreeding with purebred stock.改良品种：与纯种家畜杂交来改良（家畜）品质〔grade〕A domestic animal produced by crossbreeding one of purebred stock with one of ordinary stock.改良品种：一种家畜，由一个纯种家畜和一个普通家畜杂交得到〔blood〕Recorded descent from purebred stock.良种：有记载的纯种出身〔thoroughbred〕A purebred or pedigreed animal, especially a horse.纯种动物：尤指马等纯种或纯系动物 |