【作者】 张汤杰；

【导师】 常洪； 陈宽维；

【作者基本信息】 扬州大学 ， 动物遗传育种与繁殖， 2007， 博士

【摘要】 江淮流域悠久的历史、古老的文明和生态环境共同孵育了许多优良独特的地方水禽品种。本研究利用微卫星和线粒体两种不同的标记方法对位于我国江淮流域的高邮鸭、巢湖鸭、淮南麻鸭、沔阳麻鸭、荆江麻鸭、恩施麻鸭、微山麻鸭和攸县麻鸭8个家鸭品种的群体遗传结构特性、动物地理学、起源及系统进化进行了分析研究,为开展遗传质量监测和控制以及对我国家鸭品种资源的保护和利用提供依据。同时对位于江苏省里下河地区的高邮鸭产蛋性状进行了研究。1.筛选出28对多态性较好的微卫星标记,检测了江淮流域8个家鸭品种的遗传多样性。利用等位基因频率计算了各群体的遗传参数和群体间的遗传距离,采用邻接法和非加权组对算术平均法构建了聚类图,并进行了系统发生分析。结果表明:28个微卫星座位在我国家鸭群体中的多态信息含量大多为高度多态(26个),可以作为有效的遗传标记用于遗传多样性分析;江淮流域8个家鸭品种杂合度相差不大(0.551～0.606),以微山麻鸭的杂合度最高(0.606),其次为恩施麻鸭、荆江麻鸭和沔阳麻鸭,而攸县麻鸭的杂合度最低(0.551)。8个家鸭品种平均多态信息含量为0.481~0.524。其中恩施麻鸭最高为0.524,攸县麻鸭最低为(0.481)。结果提示,位于长江中游湖北省境内的3个家鸭品种在所研究的8个品种中遗传多样性较丰富,攸县麻鸭在8个品种中多样性最低。两种聚类方法区别不大,8个家鸭品种被聚为两大类,一大类是湖北3个家鸭品种(蛋用)首先聚类然后再与地理位置邻近的巢湖麻鸭(蛋肉兼用型)聚为一类;另外一大类是地理位置相近的微山麻鸭(蛋用型)、淮南麻鸭(蛋用型)聚类后和攸县麻鸭(蛋用型)聚为一类,最后才与高邮鸭(蛋肉兼用型)聚类。8个家鸭品种的聚类关系与品种的地理分布、育成史以及经济类型是一致的。三种遗传距离两种聚类方法得到的六种聚类结果基本一致。8个家鸭种品种之间存在显著的遗传分化,微卫星标记显示25%的遗传变异来自于品种之间的差异,江淮流域8个家鸭种群体内的个体固定系数(FIS)均值为-0.434,经检验近交程度不显著。2.利用DNA测序技术测定了位于我国中东部地区的9个家鸭品种106个个体DNA控制区多变序列,检测到34个变异位点,约占分析位点总数的5.1%,有转换、颠换、插入/缺失4种类型的变异。确定了31种单倍型,其中单倍型A7为家鸭的主体单倍型。9个家鸭品种单倍型多样度(Hd)平均为0.798,核苷酸多样度(Pi)平均为0.28%,家鸭品种单倍型多样度在荆江麻鸭中最高,在文登黑鸭中最低。对检测出的31个单倍型的分析表明:长江中游地区的家鸭品种遗传多样性高于东部地区的家鸭品种。品种之间基因流同地理距离之间呈弱负相关。各单倍型在最大简约树中的分布和实际地理分布无显著关系,各地理单元的单倍型都相互散布在不同的分布群中,呈现一种混杂的分布格局。家鸭单倍型序列的系统发生分析表明,这9个品种的家鸭只有1个母系起源,没有发现东亚斑嘴鸭对这9个家鸭品种起源有贡献的证据。3.通过对两种不同方法的比较发现,两种方法在用于遗传距离的研究中虽然绝对值不同,但是品种之间的距离关系相似或者相近;而在遗传变异结果上的差异可能与两种方法的性质和目的有关。4.高邮鸭双黄蛋性状是人工高强度选择与自然淘汰平衡的结果。本研究首次应用了群体遗传学的原理对在特定人文环境和自然地理情况下高邮鸭的双黄蛋性状进行了适应度分析。2000至2003年3年间在特定人文环境和自然地理情况下高邮鸭双黄蛋在人工选择下获得的适应度优势相当于正常蛋的8.23倍,显示出高强度的人工选择。5.催乳素(prolactin, PRL)基因内含子1存在两个Dra I酶切位点,首次发现我国家鸭在内含子1其中1个位点具有Dra I多态性。该位点由于在1 326位点发生了T→C的碱基突变。93只试验高邮鸭催乳素BB基因型个体30周龄蛋重极显著高于AB基因型个体(P<0.01);AB基因型个体的双黄率显著高于BB基因型个体(P<0.05);三种基因型间产蛋数、最长连产天数和开产体重未观察到显著差异。更多还原

【Abstract】 Centuries-old history , antiquity civilization and ecosystem along the Changjiang-Huai River incubate and cultivate many eminent and unique indigenous water bird breeds jointly. In order to develop inspect and control of genetic quality and offer basis for protect and utilization of indigenous duck breeds, microsatellite markers and the mitochondrial D-loop sequence were used to analyze the genetic characteristics, zoogeography, origin, systematic evolution biogeographic distribution pattern and evolution of 8 domestic duck breeds(Gaoyou, Caohu, Huainan, Mianyang, Jingjiang, Enshi, Weishang and Youxian sheldrake) along the Changjiang-Huai River was carried out. Egg character of Gaoyou sheldrake was investigated at the same time.1. Twenty-eight microsatellite markers with medium or high polymorphisms were selected to detect genetic diversity and genetic structure. According to the allele frequencies of 28 microsatellite sites, genetic parameters for each breed and genetic distances between breeds were calculated. UPGMA and NJ tree were completed respectively for analysis of genetic relationship among duck breeds. The results showed that 26 of 28 microsatellite sites were highly polymorphic, so the 28 markers were effective markers for analysis of genetic diversity. The discrepancy of 8 domestic duck breeds’heterozygosities was not distinct(0.551~0.606). The highest was the Weishang sheldrake(0.606), following the Enshi, Jingjiang and Mianyang sheldrake. The lowest was the Youxian sheldrake(0.551).The mean polymorphic information contents (PIC) of 8 domestic duck breeds were 0.481~0.524. The highest was Enshi sheldrake(0.524), and the lowest was the the Youxian sheldrake(0.481).The results implied that the genetic diversity of the 3 duck breeds in Hubei province were quite abundant, genetic diversity of Youxian sheldrake was the lowest among 8 duck breeds.The 8 duck breeds were divided into 2 clusters. Mianyang (egg type), Jingjiang(egg type), Enshi(egg type), and Caohu sheldrake(egg-meat type), were first cluster: Mianyang, Jingjiang and Enshi sheldrake were grouped firstly, then Caohu sheldrake was grouped with them, Huainan(egg type), Weishang(egg type), Youxian(egg type) and Gaoyou sheldrake(egg-meat type) were the second cluster: Huainan, Weishang, and Youxian sheldrake were grouped firstly, and then Gaoyou sheldrake was grouped with them. The cluster was consistent with the geographical distributing, breeding history and ecological type. There was not distinct difference between UPGMA and NJ methods or different genetic distances.There was marked genetic differentiation among 8 duck breeds by microsatellite marker research, 25% of the total genetic variation came from breed differences. The mean FIS (The fixation indices of individuals relative to its subpopulations) was–0.434, inbreeding was not significant by test.2. The mitochondrial D-loop of 106 samples collected from 9 breeds of domestic ducks were sequenced. There were 34 polymorphic sites (5.1% in total analyzed sites) found due to the transition, transversion, insertion and deletion. 31 haplotypes were identified. The major haplotype was A7. The haplotype diversity (Hd) and average nucleotide diversity (Pi) were 0.798% and 0.28%, respectively. Hd of Jingjiang shelduck was the highest among 9 duck breeds, and Hd of Wendeng black duck was lowest. The results showed the genetic diversity of mitochondrial DNA in breeds at middle reaches of Changjiang River was bigger than that at the lower reaches of Changjiang River. A unconspicuous negative correlation was observed between the estimated level of gene flow(Nm) and the geographic distance among breeds. Phylogenetic tree analysis demonstrated that no geographic clustering was observed, haplotypes were shared among geographic populations and an interwoven distribution pattern was presented.Phylogenetic analysis of the 31 haplotypes identified that there was only one distinct maternal lineage in domestic duck breeds and revealed that no evidence of contribution of Anas zonorhyncha to the maternal origin of domestic duck breeds.3. Although different absolute value of genetic distances, the relationship of genetic distances among breeds by two different methods was similar or close by the comparison of two different marker methods. The difference in genetic differentiation on two markers was probably related to the character and purpose of different marker.4. The equilibrium of high intensive artificial selection and natural selection resulted in the trait of Gaoyou duck’s double-yolk egg. The fitness of double-yolk egg trait was analyzed by population genetics for the first time one the basis of special environment and natural geography. The results showed that the double-yolk egg trait fitness was 8.23 time as the normal egg trait fitness at artificial selection during the year 2000 to 2002.5. Two Dra I recognition sites of Prolactin(PRL) gene intron 1 of Gaoyou duck were detected by PCR-RFLP and DNA sequencing, but only one polymorphism was found for the first time. A T/C mutation at the position of the 1326 bp of the PRL gene was found by DNA sequencing The least square analysis showed that the BB ducks had significant egg weight at the age 30 weeks than AB ducks (P<0.01), the double-yolk percentage of the AB ducks was much higher than that of BB ducks (P<0.05) in double-yolk ducks, but there was not significant difference in egg number, longest clutch days and the body weight at first egg among 3 genotypes.更多还原