【作者】 刘铸；

【导师】 田秀华； 白素英；

【作者基本信息】 东北林业大学 ， 特种经济动物饲养， 2006， 硕士

【摘要】 大鸨(Otis tarda)是国家Ⅰ级保护动物,CITES附录Ⅱ物种。近年来的调查发现东方亚种数量在逐渐减少。为了解东方亚种濒危的现状并为制定科学、有效的保护措施提供科学依据,本研究利用核微卫星DNA和mtDNA控制区序列,从父系和母系两方面对大鸨东方亚种的遗传多样性进行了研究。微卫星DNA研究显示,从3个大鸨指名亚种的微卫星位点和13个波斑鸨的微卫星位点中筛选出8个具有多态性的位点。其中有3个微卫星位点的多态性较低,其余5个位点的多态性较高。在47个个体的种群中,各位点的观察杂合度(H_o)为0.0435-1.0000,平均为0.6595;各位点多态信息含量(PIC)为0.0416-0.8520,平均为0.5497;有效等位基因数(E)为1.04-7.46,平均为3.61。4个位点符合Hardy-Weinberg平衡,4个位点不符合Hardy-Weinberg平衡。mtDNA控制区序列分析中,对控制区Ⅰ和Ⅱ的3段序列及3段序列的全长进行了分析,引物CtrlaL/CtrIIoH间序列含有8个单元型,核苷酸多态性(π)为0.00328、单元型多态性(d)为0.622和核苷酸差异均数(K)为1.116;引物L438/H772间序列没有变异;引物LCR2a/HCR8间序列仅1个变异;引物CtrIaL/HCR8间序列含有7个单元型,核苷酸多态性(π)为0.00174、单元型多态性(d)为0.718和核苷酸差异均数(K)为1.359。综合比较发现,中国大鸨东方亚种核DNA和mtDNA的遗传多样性水平均很低,且低于指名亚种,这可能由于自身特点、历史瓶颈、分布地域紧缩和生境破碎化等原因造成的。系统分析显示,松辽平原西北部繁殖区与乌兰察布高原繁殖区存在基因流共为一个进化显著性单元,但二者还拥有各自特有的单元型,可作为不同的管理单元进行管理。鉴于东方亚种的濒危境地,首先,要重视越冬地的保护;其次,要保护好重要繁殖区:最后,建立一个拥有现有遗传多样性水平的迁地保护种群,既可避免其遗传多样性的进一步丧失,又可为扩大野外种群的规模奠定基础,从而使其逐渐摆脱濒危境地,达到大鸨物种保护的目的。更多还原

【Abstract】 Great bustard （Otis tarda） is listed as a first-rating protected bird in China and CITES II. The number of great bustard （Otis tarda dybowskii） is decreasing recently in China. In order to find the reason of population decline and assist conservation, the genetic diversity of great bustard was analyzed by microsatellite DNA and mtDNA control region markers. In study using microsatellite DNA markers, Three microsatellites from great bustard （O. t. tarda） and 13 microsatellites from Houbara bustard （Chlamydotis undulate） were detected in 47 great bustards （O. t. dybowskii）. Eight microsatellites loci were polymorphic, 3 loci of which were low polymorphic and the remaining 5 loci were highly polymorphic. The heterozygosity （H₀）of the 8 loci ranged from 0.0435 to 1.0000, averaging 0.6595 per locus, the Polymophism Information Contant （PIC） of the 8 loci ranged from 0.0416 to 0.8520, averaging 0.5497 per locus, and the effective number of alleles （E） of 8 loci ranged from 1.04 to 7.46, 3.61 alleles per locus on average. The observed genotype frequencies at 4 loci were consistent with Hardy-Weinberg Equilibrium （HWE） and the remaining 4 loci were significantly deviated from HWE. In study of O. t. dybowskii using mtDNA control region markers, three regions and the total region of mtDNA control region I and II were analyzed. Amplification of CtrIaL/CtrIIoH had 8 haplotypes, Nucleotide diversity（л） was 0.00328, Haplotype diversity （d） was 0.622, Average number of differences （K） was 1.116;Amplification of L438/H772 hadn’t mutation;Amplification of LCR2a/HCR8 only had 1 mutation;The total region of CtrIaL/HCR8 had 7 haplotypes, Nucleotide diversity （Jl） was 0.00174, Haplotype diversity （d） was 0.718, Average number of differences （K） was 1.359. The results show that genetic diversity of O. t. dybowskii is lower than O. t. tarda through compare of many aspects. This may be caused by the fewer total number, genetic bottleneck in history and concentrated geographical distribution, northwest of Songliao plain and Wulangchabu plateau breeding areas are a evolutionary significant unit, two breeding areas have own haplotype, then administer them as two Conservat ion un its. In view of the fact that the O. t. dybowskii are in imminent danger, first, must take importance to protection of wintering areas;Next, must try our best to protect the important breeding areas;Finally, establishes a population including existing genetic diversity for reintroduction, thus enable it to get rid gradually is in imminent danger, achieves the bustard species protection the goal.更多还原