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何道领 《上海畜牧兽医通讯》2011,(1):29-30
地方畜禽品种资源是生物多样性的重要组成部分,其多样性的保护直接关系到畜牧业的可持续发展。本文在对重庆市13个国家级畜禽遗传资源及3个获得国家认可的国家级畜禽遗传资源的重要类群的调查研究基础上,分析评价了畜禽品种资源受威胁的程度。 相似文献
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遗传多样性也称基因多样性,自达尔文1859年在《物种起源》中将可遗传的变异称为多样性,科研人员就开始了对畜禽遗传资源多样性的研究利用。对野猪资源而言,遗传多样性指猪及其野生近缘种的种问和种内不同种群之间或群体内不同个体的遗传变异的总和。对遗传多样性的早期研究主要是形态学水平上研究,而后经历细胞水平、生理生化水平研究。近年人们在DNA分子水平上开展遗传多样性研究,开始利用DNA分析手段选育品种和寻找具有优良生产性能的基因,为开发利用与物种保护提供依据,并取得许多有价值的成果．本文主要从野猪染色体的遗传多样性、DNA水平的遗传多样性和野猪部分核内基因的多态性进行概述。 相似文献
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遗传多样性与畜禽品种资源的保存利用 总被引：9，自引：0，他引：9
本文论述了畜禽遗传多样性的概念、主要表现形式及研究方法 ,介绍了我国畜禽品种资源的保存利用状况 ,并指出了遗传多样性的研究在畜禽品种资源保存利用中的理论和实际意义 相似文献
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我国地方鸡种遗传多样性的研究现状 总被引：1，自引：0，他引：1
遗传多样性是生物多样性的核心和重要组成部分。遗传多样性是指遗传信息的总和,蕴藏在地球上各种植物、动物和微生物个体的基因中。一般主要是指种内不同群体之间或群体内不同个体中的遗传变异的总和。畜禽是人类长期强度选择和杂交培育的产物,积累了丰富的遗传变异,形成了各具特色的品种。畜禽遗传多样性的研究有助于了解畜禽及其品种的进化历史、分类地位和相互关系,为畜禽资源的保存利用提供理论依据。 中国是世界上家禽驯化最早,品种资源最丰富的国家之一,是世界各国养禽十分关注的巨大基因库。中国的地方鸡种品种多、分布广,遗… 相似文献
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近几十年来，我国由于保种措施不当和盲目的引进外来品种进行杂交，从而导致家禽品种资源日益减少，品种失去了其丰富的遗传多样性，特别是一些隐性遗传的优势基因的丢失，而进行畜禽品种的遗传距离测定和聚类分析是畜禽多样性估测、利用和保护的基础性工作，因此，测定畜禽物种内各品种间的遗传距离，为保种对象的确定提供依据成为目 相似文献
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中国是世界上畜禽遗传资源最丰富的国家之一,截至2021年,收录于《国家畜禽遗传资源品种名录》(2021年)中的猪品种共有102个,其中地方品种83个,占总品种数量的81.37%。基于畜禽遗传资源保护视角下,探讨我国地方猪品种资源保护很有必要。文章分析了当前地方品种猪资源的存在情况、社会层面对优质地方畜禽资源的认识、地方畜禽品种保护工作的组织体系和保护体系以及保护方式和手段等方面存在的问题,并提出了建立多方参与保护机制、施行地方物种抢救性保护工程,建立基因库、丰富遗传多样性,加强宣传引导、提高农民保护积极性等合理化的对策与建议,为我国地方品种猪资源保护与利用提供相关理论依据。 相似文献
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畜禽种质资源的多样性为人类提供了各种生活资料,维持了自然界的生态平衡,是维护国家生态安全的重要物质基础,是实现畜牧业可持续发展的主要战略资源。但据联合国粮农组织最新的统计显示,全球约8%的畜禽品种已经灭绝,22%的畜禽品种正面临灭绝的危险。这说明动物遗传资源多样性的现状不容乐观,采取有效措施遏制畜禽遗传资源多样性的减少已刻不容缓。本次大会报告上,吴常信就如何保护 相似文献
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猪品种遗传多样性的研究进展 总被引：3，自引：1，他引：2
从猪品种的体型外貌、染色体带型、血型和蛋白质以及DNA分子水平等几个方面对猪的遗传多样性进行论述 ,并对遗传多样性的度量参数作了分析。认为猪种遗传多样性的研究是保种和利用的理论基础 ,从形态到DNA分子水平对猪品种遗传多样性的研究在遗传资源大量流失的今天具有重要意义。 相似文献
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Molecular characterization of breeds and its use in conservation 总被引：3，自引：0，他引：3
The conservation of farm animal resources is important for coping with future breeding needs and for facilitating the sustainable use of marginal areas. The increasing availability of molecular markers for most farm animal species and the development of techniques to analyse molecular variation is widening our capacity to characterise the genetic variation of breeds. In this paper we review the most popular molecular markers used in conservation and animal breeding studies, the different measures of genetic diversity that they provide, and their application for managing within-breed genetic diversity and for setting between-breed conservation priorities. We also address the relationship between genomic and marker heterozygosity, the relationship between molecular and quantitative measures of genetic diversity, and the characterization of breeds based on non-neutral markers. 相似文献
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Between-breed genetic diversity is classically considered as a major criterion to be taken into account when setting priorities for conservation of domestic animal breeds. However, it has been argued that methods based on the between-breed component of genetic diversity may not be optimal because they ignore the within-breed component of variation. The paper considers the most common methods used to evaluate those two components when genetic diversity is evaluated on the basis of genetic markers, and proposes to define an aggregate diversity combining linearly the two components. This implies defining for each breed (or population) its contributions to the between-breed and to the within-breed diversity. When defining an aggregate diversity, one can weight these contributions by FST and 1−FST, respectively, since the fixation index FST of Wright represents the proportion of the total genetic variation which is due to differences in allelic frequencies between populations. Such an approach is valid when the objective is genetic improvement by selection within a so-called “meta-population”. However, in a more general context of animal breeding, when heterosis and complementarities between breeds have to be considered, as well as adaptation to specific environments, more weight should be given to the between-breed variation. The proper weight to apply may require solutions adapted to each particular situation. In a long-term conservation perspective, priorities should also take into account the degree of endangerment of each breed. By combining diversity contributions and probability of extinction, a cryopreservation potential (or priority) may be estimated for each breed. The problem is illustrated on a sample of 11 European pig breeds typed for 18 microsatellite loci. 相似文献
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M.-L. Glowatzki-Mullis J. Muntwyler E. Bäumle & C. Gaillard 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2009,126(2):164-175
There is constant pressure to improve evaluation of animal genetic resources in order to prevent their erosion. Maintaining the integrity of livestock species as well as their genetic diversity is of paramount interest for long-term agricultural policies. One major use of DNA techniques in conservation is to reveal genetic diversity within and between populations. Forty-one microsatellites were analysed to assess genetic diversity in nine Swiss sheep breeds and to measure the loss of the overall diversity when one breed would become extinct. The expected heterozygosities varied from 0.65 to 0.74 and 10.8% of the total genetic diversity can be explained by the variation among breeds. Based on the proportion of shared alleles, each of the nine breeds were clearly defined in their own cluster in the neighbour-joining tree describing the relationships among the breeds. Bayesian clustering methods assign individuals to groups based on their genetic similarity and infer the number of populations. In STRUCTURE, this approach pooled the Valais Blacknose and the Valais Red. With BAPS method the two Valais sheep breeds could be separated. Caballero & Toro approach (2002) was used to calculate the loss or gain of genetic diversity when each of the breeds would be removed from the set. The changes in diversity based on between-breed variation ranged from −12.2% (Valais Blacknose) to 0% (Swiss Black Brown Mountain and Mirror Sheep); based on within-breed diversity the removal of a breed could also produce an increase in diversity (−0.6% to + 0.6%). Allelic richness ranged from 4.9 (Valais Red) to 6.7 (Brown Headed Meat sheep and Red Engadine Sheep). Breed conservation decisions cannot be limited to genetic diversity alone. In Switzerland, conservation goals are embedded in the desire to carry the cultural legacy over to future generations. 相似文献
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Blackburn HD Paiva SR Wildeus S Getz W Waldron D Stobart R Bixby D Purdy PH Welsh C Spiller S Brown M 《Journal of animal science》2011,89(8):2336-2348
Understanding existing levels of genetic diversity of sheep breeds facilitates in situ and ex situ conservation activities. A comprehensive evaluation of US sheep breeds has not been previously performed; therefore, we evaluated the genetic diversity among and within 28 US sheep breeds. Both major and minor breeds were included in the analysis and consisted of 666 animals from 222 producers located in 38 states. The level of within-breed genetic diversity was variable and not dependent upon status of a breed as a major or minor breed. Bayesian cluster analysis indicated the breeds were grouped more by physiological differences (meat vs. wool production) rather than geographic origin. Results suggest several actionable items to improve in situ and ex situ conservation. The results clearly identify breeds in need of increased in situ and ex situ management (e.g., Hog Island and Karakul) and allow several suggestions for in situ management of flocks. Conversely, several of the breeds appear genetically similar and therefore require less emphasis on collecting germplasm samples for the gene bank. Commercially important breeds (e.g., Rambouillet and Suffolk) were found to have substantial variation, which should enable breeders to proceed, unencumbered by genetic diversity concerns, with selection strategies that maximize profit. 相似文献
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Morris CA Towers NR Hohenboken WD Maqbool N Smith BL Phua SH 《New Zealand veterinary journal》2004,52(5):205-215
Facial eczema (FE) is a costly problem to New Zealand pastoral agriculture, and has a detrimental impact on animal wellbeing. Incidence and severity of the disease can be reduced by grazing management and zinc prophylaxis. An additional strategy is to breed animals that are genetically resistant to intoxication with sporidesmin, the causative mycotoxin. This review summarises research findings on the inheritance of resistance of animals to FE, including evidence of among- and within-breed genetic variation, direct and correlated responses to selection, and identification of genetic markers and candidate genes for FE resistance. 相似文献
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遗传多样性的研究主要包括形态学水平,染色体水平、蛋白质水平、DNA水平等。中国地方鸡种类繁多,研究地方鸡种的遗传多样性,不仅能加强生物多样性的保护,同时对起源、进化、分类鉴定及遗传育种等都有重要意义。20世纪80年代以来,分子生物学技术的快速发展为遗传多样性检测提供了更直接、更精确的方法,即直接通过分析DNA水平的序列变化检测动物遗传多样性。DNA分析方法成为目前最有效的遗传分析方法,避免了根据表型性推断基因型时可能产生的误差。作者对目前中国各种鸡群的遗传多样性在DNA水平的研究进行了综述,旨在发掘地方鸡种的优良基因,为地方鸡种的分子育种、改良提供参考。 相似文献
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青藏高原和新疆地区垂穗披碱草种质的SRAP及RAPD分析 总被引：3，自引：0，他引：3
使用SRAP和RAPD标记对采集自我国青藏高原和新疆地区的64份垂穗披碱草(Elymus nutans Griseb.)进行遗传多样性和亲缘关系分析,并测其遗传变异和各地理类群的遗传多样性水平。结果表明:2种标记都显示供试材料具有较高的遗传多样性水平(PPB=85.86%,90.39%),且新疆地区材料的遗传多样性水平高于青藏高原地区,它们分别得到相似但并不完全相同的聚类图,相似生态地理环境的材料可以聚为一类;2种标记的分子方差分析(AMOVA)揭示了地理类群内部和地理类群间分别有48.23%,39.87%和51.77%,60.13%的变异;通过2种标记的比较分析,SRAP能更高效地对垂穗披碱草种质进行遗传变异分析;青藏高原和新疆地区的材料存在明显的遗传分化,气候和山脉等生态地理条件以及繁育系统等可能是使材料发生遗传变异的重要因素。这些结果将为垂穗披碱草种质的育种以及种质资源的收集和保存提供基础依据。 相似文献
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随着科技和现代生物技术的迅猛发展,国际竞争会越来越激烈.包括畜禽在内的生物遗传资源已成为一个国家可持续发展的重要战略资源,资源的拥有国对该资源具有国家主权.国际社会对生物资源也十分重视,有关生物遗传资源的许多国际公约、条约等法律法规相继签署生效,促进了全球畜禽遗传资源的管理、保存和利用.本文对联合国(UN)、世界贸易组织(WTO)以及世界知识产权组织(WIPO)等国际组织相关的畜禽遗传资源管理方面的法律法规进行了研究,通过分析各项法律法规的宗旨、目标、应用条件和适用范围以及国际立法新的方向,为更有效地保护我国畜禽遗传资源,以及进行全面管理、利用和国际交流提供法律方面的参考. 相似文献
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H Woelders J Windig SJ Hiemstra 《Reproduction in domestic animals = Zuchthygiene》2012,47(Z4):264-273
Many local breeds are currently at risk because of replacement by a limited number of specialized commercial breeds. Concurrently, for many breeds, allelic diversity within breeds declines because of inbreeding. Gene banking of germplasm may serve to secure the breeds and the alleles for any future use, for instance to recover a lost breed, to address new breeding goals, to support breeding schemes in small populations to minimize inbreeding, and for conservation genetics and genomics research. Developments in cryobiology and reproductive technology have generated several possibilities for preserving germplasm in farm animals. Furthermore, in some mammalian and bird species, gene banking of material is difficult or impossible, requiring development of new alternative methods or improvement of existing methods. Depending on the species, there are interesting possibilities or research developments in the use of epididymal spermatozoa, oocytes and embryos, ovarian and testicular tissue, primordial germ cells, and somatic cells for the conservation of genetic diversity in farm- and other animal species. Rapid developments in genomics research also provide new opportunities to optimize conservation and sampling strategies and to characterize genome-wide genetic variation. With regard to gene banks for farm animals, collaboration between European countries is being developed through a number of organizations, aimed at sharing knowledge and expertise between national programmes. It would be useful to explore further collaboration between countries, within the framework of a European gene banking strategy that should minimize costs of conservation and maximize opportunities for exploitation and sustainable use of genetic diversity. 相似文献