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971.
Half of 23 Belgian dog breeds has a compromised genetic diversity,as revealed by genealogical and molecular data analysis 下载免费PDF全文
K. Wijnrocx L. François A. Stinckens S. Janssens N. Buys 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2016,133(5):375-383
The genetic diversity in 23 dog breeds raised in Belgium was investigated using both genealogical analysis and microsatellite markers. Some of these breeds are native breeds, with only small populations maintained. Pedigree and molecular data, obtained from the Belgian kennel club, were used to calculate the inbreeding coefficients, realised effective population size as well as probabilities of gene origin and average observed heterozygosity. Inbreeding coefficients ranged from 0.8 to 44.7% and realised effective population size varied between 3.2 and 829.1, according to the used method and breed. Mean observed heterozygosity ranged from 0.47 to 0.73. Both pedigree and molecular methods reveal low genetic diversity and presence of bottlenecks, especially in native Belgian breeds with small population sizes. Furthermore, principal component analysis on the set of investigated diversity parameters revealed no groups of breeds that could be identified in which similar breeding strategies could be applied to maintain genetic diversity. 相似文献
972.
Kyung-Won HONG Miho INOUE-MURAYAMA Akihiro NAKAMURA Kenji NAGAO Shin'ichi ITO 《Animal Science Journal》2008,79(5):641-643
We surveyed two polymorphic microsatellites in a candidate gene for fear response, monoamine oxidase A ( MAOA ), in chicken. Two hundred and eighty chickens from five breeds (Nagoya, Mikawa, White Leghorn, White Plymouth Rock, and Rhode Island Red) were investigated. A thymine (T) repeat and an adenine (A) repeat were found on MAOA intron 4 ( CMin4T ) and intron 9 ( CMin9A ), respectively. Nine alleles ( 127-bp to 166-bp ) in CMin4T and six alleles ( 184-bp to 198-bp ) in CMin9A were detected. A 128-bp allele in CMin4T was observed in the Nagoya breed only, implying a highly useful marker for discriminating the Nagoya breed from other breeds. In addition, the Mikawa breed had the fixed 127-bp and 198-bp alleles in CMin4T and CMin9A , respectively. The Nagoya breed chickens show densely cowardly behavior, but the Mikawa breed chickens do not show the same behavior. The current results may indicate that MAOA is an informative candidate gene for breed difference. 相似文献
973.
选取凉山半细毛羊7个父系半同胞家系,利用绵羊1号染色体上11个微卫星标记,通过聚合酶链式反应(polymerase chain reaction,PCR)对凉山半细毛羊初生重QTL进行了研究。QTL分析的结果表明,在其中一个家系B3K5055中,1号染色体微卫星标记ILSTS004与CSSM004之间检测到影响初生重的QTL,其LOD值为3.338,位于置信区间95%(2.73)和99%(3.49)之间。 相似文献
974.
荣昌猪是我国优良地方品种,巴马香猪和贵州小型香猪为我国独特小型猪品系。本研究采用美国猪基因组协作计划推荐的19个微卫星标记对荣昌猪、荣昌猪B系、巴马香猪、贵州小型香猪及外来猪种大白猪进行了遗传学检测和分析。结果表明:19个微卫星位点在群体中均表现为多态,每位点等位基因数10~23个。5个猪种中荣昌猪B系的遗传多样性最高,荣昌猪次之;2种小型猪的遗传多样性较低,其中巴马香猪的等位基因数(121个)略大于贵州小型香猪(114个),但其遗传多样性指数(平均期望杂合度0.6535±0.0347)小于贵州小型香猪(0.6919±0.0227),反映了巴马香猪较低的基因杂合度和较小的遗传变异;大白猪的遗传多样性最低。从品系的共有等位基因来看,荣昌猪B系基因背景组成中其亲本品系荣昌猪所占比例(30.22%)要大于大白猪(24.37%);大白猪和其他4个猪群体的共享等位基因数均较低(21.24%~25.12%);巴马香猪和贵州小型香猪之间共有等位基因数最高(45.06%)。采用基于遗传距离的NJ法和基于基因频率的最大似然法进行系统聚类,除了大白猪明显为独立分支及荣昌猪B系表现出较远的聚类关系外,其他3个猪种间的聚类有所不同。 相似文献
975.
C Dalvit M De Marchi R Dal Zotto E Zanetti T Meuwissen M Cassandro 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2008,125(2):137-144
The present study was a contribution on the genetic characterization of the Burlina local cattle breed, and an approach to understanding the relationships between Burlina, Holstein Friesian and Brown Swiss which represent the majority of the dairy cattle reared nowadays in North-East Italy. The obtained results helped to clarify the genetic diversity and distinctiveness of Burlina population. In particular, the low genetic distance between Burlina and Holstein Friesian and the assignment of a moderate percentage of Burlina animals to Holstein Friesian suggested that crosses between them took place in the past, while crosses with Brown Swiss seemed to be less frequent. However, analyses of marker genotypes, showed a cluster with only Burlina individuals, which demonstrates the genetic distinctness of this breed. The Burlina breed showed the highest variability among the analysed breeds and its inbreeding coefficient was low. The data contribute to the feasibility of a conservation and selection programme for this breed and the results are useful for the implementation of a conservation strategy that should aim to conserve animals where the contribution from foreign breeds is as small as possible. 相似文献
976.
边鸡微卫星DNA标记遗传多样性的研究 总被引:4,自引:0,他引:4
利用鸡基因组中5个微卫星标记,检测了边鸡群体的遗传多样性,并以大骨鸡做了比较分析。同时探讨了边鸡在国内5个地方鸡种中的系统地位。结果表明,5个微卫星位点共检测到38个等位基因,其中ADL0146位点的等位基因数最少(5个),而ADL0136和ADL0185两个位点的等位基因数最多(9个),平均等位基因数为7.6个.边鸡群体内比大骨鸡群体有更丰富的遗传多样性。聚类分析结果显示,边鸡与大骨鸡亲缘关系最近。而与鲁西斗鸡亲缘关系最远。 相似文献
977.
部分地方鸡种微卫星DNA指纹分析 总被引:2,自引:0,他引:2
利用20个微卫星标记对我国19个地方鸡种保种群进行了遗传检测,计算各群体的等位基因频率、平均基因杂合度、平均多态信息含量及各群体间的遗传距离,并用类平均法进行聚类分析。研究结果表明:20个微卫星标记在19个地方鸡种保种群共检测到184个等位基因,平均为9.2个,基因频率分布在0.013-0.838之间。19个地方鸡种平均杂合度在0.5824-0.7432之间。其中藏鸡最高,白耳鸡最低。平均多态信息含量在0.5238-0.7023之间,均大于0.5,表现为高度多态性;19个鸡种聚为6类。各鸡种的遗传距离及聚类结果与所保存的地方鸡种的地理分布、现实状况是相吻合的,从而表明用该方法分析品种间的亲缘关系是可行的。 相似文献
978.
Artemis Rumbou Cesare Gessler 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(4):379-392
Oilspots of the Plasmopara viticola population in a Greek vineyard over 2 years were collected and the pathogen genotyped with the use of four microsatellite loci. In 2001, five samplings occurred and 327 lesions were collected, which were classified to 23 genotypes. In 2002, the 426 lesions collected in four samplings belonged to 54 genotypes. A reproducible pattern of the evolution of the epidemic was exhibited that can be described as 'predominance-of-one-clone'. In 2001, the predominant clone covered 72–92% of each sample, while in 2002 the incidence of the predominant clone was 38–90%. The remaining genotypes showed low clonal reproduction and dispersal. Oosporic infections occurred throughout the season. The severity and the diversity in 2002 were, however, higher than in 2001 and this was not in accordance with the climatic conditions, suggesting that other factors, like the epidemic of the previous year, also influence the epidemic of the disease. These results produce new concepts about the epidemiology of the pathogen. 相似文献
979.
Rahmutulla Abdukerim Zilajigvl Ekram NING Li-qun Guzalnur Zibibilla Ezizjan Nabi Buzohra Tursun Shamshidin Abduriyim Mahmut Halik 《中国畜牧兽医》2015,42(9):2436-2443
For scientific evaluation, protection and utilization of the valuable resources of 53 captive Tianshan Red deers (CJ, n=31;HM, n =22), the genetic polymorphisms of 8 microsatellites, analyzed the genetic diversity, genetic diversity and kept in captivity Tianshan Red deer was discussed.Microsatellite data indicated that 8 loci alleles were 3 to 7, 37 alleles were detected.The results showed that genetic diversity of Shenghua domesticated Red deer breeding base were A=4.625, He=0.6398, Ho=0.5887, PIC=0.5851, Ne=2.8357, Fis=0.0338, Hami Red deer farm field were A=4.375, He=0.6888, Ho=0.6818, PIC=0.6238, Ne=3.2078, Fis=-0.0175.The two population was not significantly deviated from Hardy-Weinberg equilibrium (HWE).It suggested that the genetic diversity of the captive Tianshan Red deer from two areas was still higher, however the date of F-statistics indicated that the captive Tianshan Red deer in Changji exchanged individuals resulting to inbreeding. Therefore, at the present, the focus of management of captive Red deer population should shift to avoiding the inbreeding and the loss of genetic diversity. 相似文献
980.
BAI Jun-yan PANG You-zhi ZHANG Xiao-hui YUN Yin-xian ZHAO Shu-juan QI Yan-xia 《中国畜牧兽医》2015,42(9):2444-2452
In order to reveal the genetic structure and genetic relationship of Korean quail, Chinese Yellow quail, Chinese Black quail, the 3 quail populations from the molecular level, to provide for the study of genetic resources of quail.This study used PCR amplification, polyacrylamide gel electrophoresis, cluster analysis and other methods of 3 quail populations were polymorphic analysis of microsatellite markers.The results showed that 12 microsatellite markers in 3 quails was detected in the observed number of alleles was between 4 and 7, the average polymorphism information content of Chinese Yellow quail, Chinese Black quail, Korean quail were 0.6853, 0.6401 and 0.6565, respectively;The average heterozygosity were 0.7333, 0.6957 and 0.7111, respectively, which Chinese Yellow quail population genetic diversity was the most abundant polymorphism.The cluster analysis showed that the Chinese Black quail and Korean quail smallest genetic distance was 0.0628, so the Chinese Black quail and Korean quail were clustered into one category, and then was Chinese Yellow quail together.This was further evidence of Chinese Black quail and Korean quail had a closer genetic relationship, and the genetic relationship of Chinese Black quail and Korean quail was more distant with Chinese Yellow quail. 相似文献