早胜牛及其杂交群体遗传多样性研究  

The Genetic Diversity of Zaosheng Native Cattle(Bos taurus) and Associated Crossbred Population

作　　者：刘丽[1] 赵生国[1,2] 蔡原[1] 雷赵民[1,2] Michael A.Brown 王建福[1,2] 张长庆[1] 吴建平[1,2] 

机构地区：[1]甘肃农业大学动物科学技术学院,兰州730070 [2]中美草地畜牧业可持续研究中心,兰州730070 [3]美国农业部放牧草地研究室,俄克拉荷马州埃尔里诺市73036

出　　处：《农业生物技术学报》2014年第3期317-325,共9页Journal of Agricultural Biotechnology

基　　金：甘肃省农业生物技术研究与应用开发项目(No.GNSW-2010-04和No.GNSW-2011-27);甘肃省高等学校科研项目(No.2013A-063和No.2013A-069)

摘　　要：主产于甘肃庆阳的早胜牛先后迁徙到平凉、固原等周边地区,在长期的适应性驯化中,形成了具有各自遗传特征的地方性类群。本研究对6个早胜牛(Bos taurus)类群(庆阳类群、平凉类群、固原类群、南德温与庆阳类群杂种、西门塔尔与平凉类群杂种、秦川牛与固原类群杂种)共166个个体线粒体DNAD环部分片段进行了分析,在长度为612 bp的序列中,共检测到131个变异位点,界定了103个单倍型。结果表明,早胜牛庆阳、平凉和固原3个地方类群的平均核苷酸差异数(13.884,10.266和3.111)和核苷酸多样度(0.022 95,0.016 82和0.005 11)依次降低,与3个杂交类群的结果类似(15.362,9.264和7.495;0.025 31,0.0152 4和0.012 33);3个地方类群的共享单倍型数和特有单倍型数均以庆阳类群为最高(6和32),平凉类群(6和9)和固原类群(2和5)分别依次降低,3个杂交类群(11和17;9和16;8和9)也有类似结果;就对维持早胜牛总体多样性而言,早胜牛庆阳类群及其杂交类群、早胜牛平凉杂交类群具有正效应,而早胜牛平凉类群、早胜牛固原类群及其杂交类群均起到不同程度的负效应。认为早胜牛庆阳类群及其杂交类群的遗传多样性高于其他两个地方类群及其杂交类群,杂交类群遗传多样性分布规律与其对应的地方类群一致,没有受到杂交影响,说明早胜牛杂交类群是引入父本的杂交方式,同时也说明平凉和固原早胜牛可能相继从早胜牛的主产区庆阳迁徙而来,逐渐形成两个母系分枝,这将为早胜牛的遗传资源保护提供更多的科学依据。Maternally inherited mitochondrial DNA （mtDNA） has been used extensively to determine genetic diversity, guide genetic resource conservation, and determine phylogeny. Zaosheng cattle, mainly produced in Qingyang Prefecture of Gansu, were introduced to Pingliang, Guyuan, and other areas coinciding with the growth of farming culture. Local genetic groups in various locations were formed through long term domestication and adaptation, respectively. To investigate the genetic diversity of Zaosheng cattle, six Zaosheng cattle groups （Qingyang group, QZ; QZx South Devon group, QZxN; Pingliang group, PZ; PZxSimmental, PZxX; Guyuan group, GZ; GZxQinchuan cattle, GZxQ） were analyzed using mtDNA D-loop. A total of 131 variable sites and 103 haplotypes were identified. Among the QZ, PZ and GZ groups, the average number of nucleotide differences （13.884, 10.266, 3.111, respectively） and nucleotide diversity （0.022 95, 0.016 82, 0.005 11, respectively） decreased. Similar results were observed in QZxN, PZ^X and GZxQ groups （15.362, 9.264, 7.495, respectively; and 0.025 31, 0.015 24, 0.012 33, respectively for nucleotide differences and diversity）. There were 6 shared and 32 unique haplotypes found in the QZ group, which was greater than PZ（6 shared, 9 unique）and GZ （2 shared, 5 unique）. In conclusion, the genetic diversity of QZ and QZxN was higher than other groups, and the genetic diversity of crossbred groups was similar to native groups. Consequently, crossbreeding had little influence on mtDNA genetic diversity in Zaosheng cattle and crossbreeding of Zaosheng cattle was generally through paternal crosses. We can also draw a conclusion that Zaosheng cattle in Pingliang and Guyuan could have migrated from Qingyang and gradually formed two maternal branches and provide a scientific foundation for genetic resources conservation of Zaosheng native cattle.

关 键 词：早胜牛 线粒体DNA D—loop 遗传多样性 单倍型遗传贡献 

分 类 号：S82[农业科学—畜牧学]