广西杂交水牛的遗传特性及选育方向

GENETIC CHARACTERISTICS OF CROSSBRED BUFFALOES AND THEIR OBJECTIVE OF BREEDING AND SELECTING IN GUANGXI

用么拉、尼里/拉菲水牛与广西本地水牛进行杂交,杂种优势明显,继承了双亲的优点,但多是父本显性遗传。具有良好的乳肉生产潜力,年均产奶量1800～2600kg,屠宰率50～57％。经比较,以三品种杂交和尼本杂交为最佳组合。由于双亲染色体组型(父本2n=50、母本2n=48)的差异,其杂交水牛的染色体组型必然表现多态性(2n=50或2n=49或2n=48),在选育上除考虑乳肉生产性能外,还应将2n=50的染色体组型作为一项重要的选择指标。选择乳牛兼用型杂交水牛,符合我国当前农村经济发展水平及人民群众的需要,是当前杂交水牛的选育方向。

The work on the crossbreeding of local female buffaloes with Murrah and Nili-Ravi bulls has been carried out for 30 years in Guangxi. It has been shown that the crossbreds had an obvious hybrid vigor and inheritance in the good performance traits from their parents. In most cases the crossbred buffaloes showed a paternal inheritance, so they generally have a good potential for milk and meat production (1800~2600kg in milk and 50~57% in dressing percentage) . The animal bred in three-way cross (N×M×L) and the offsprings of local breed crossed with Nili-Ravi had the optimal heterotic effect compared with the others. However, a polymorphism of karyotype inevitablly occur in the crossbred buffaloes (2n=50, 2n=49 or 2n=48) because of the different karyotype in their parents ( =50, = 48) , so in the breeding and selecting of the animals, we should choose the karyotype of the crossbreeds being 2n = 50 as a main target except the traits for meat and milk yield. To meet the meat and milk requirment of consumers, the objective of breeding and selecting on the crossbreds should be put on a double purpose, meat and milk.