A.1/2 B.3/4 C.1/3 D.2/3
A.產(chǎn)品獨特 B.肉質(zhì)好 C.飼料轉(zhuǎn)化率高 D.產(chǎn)仔數(shù)目多
A.簡單雜交 B.引入雜交 C.級進雜交 D.三元雜交