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牛是重要的家畜之一,在役用、肉用和乳用等方面对社会有着重要的贡献。通过鉴定牛经济性状相关基因及其变异有助于提高育种效率,增加经济效益。随着现代生物技术的发展,对牛经济性状主效基因的挖掘变得更加准确。已鉴定与牛生长发育相关的PLAG1基因,与繁殖相关的GDF9基因,与肉质相关的CAST基因,与胴体相关的MSTN基因,与毛色相关的MC1R基因,与泌乳相关的DGAT1基因等。针对牛不同性状进行合理的分子选育对牛业发展有着重要的经济价值和意义。本文对近年来黄牛生长发育性状、繁殖性状、肉质性状、胴体性状、毛色性状和泌乳性状主效基因研究进展进行综述,为今后黄牛遗传育种研究提供参考依据。 相似文献
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北京地区荷斯坦青年牛繁殖性状影响因素分析 总被引：1，自引：0，他引：1
本研究利用北京地区23个奶牛场105头公牛的25705个女儿繁殖记录,对中国荷斯坦青年牛的4个繁殖性状,包括青年牛初配日龄（AFI）、青年牛妊娠日龄（AFP）、青年牛初产日龄（AFC）和输精次数（NS）,采用固定模型通过SAS9.1软件GLM过程进行统计分析。结果表明,牛场、出生年份、出生季节以及公牛等效应对青年牛繁殖性状具有显著（P〈0.05）或极显著影响（P〈0.01）。通过提高饲养管理水平,给母牛创造良好的生存环境,选用具有优秀繁殖性能的种公牛,可有效提高母牛繁殖效率。 相似文献
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繁殖障碍的发生几乎都是遗传与环境因素相互作用的结果,因而育种方法有助于减少各种繁殖障碍的蔓延,并且随着牛生产性状遗传进展的累积,必须将在经济重要性方面不低于产肉、产奶等性状的繁殖障碍纳入育种计划中。本文以上述观点为基点,综述了牛的繁殖障碍的遗传性影响因素,介绍了繁殖障碍的几种遗传学分析方法,阐述了控制遗传性繁殖障碍的4项育种措施,提议以寻求适当的标记性状作为繁殖障碍遗传流行病学研究和临床诊断指标的突破口。 相似文献
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为了选育中国西门塔尔牛肉用品系,本研究从中国肉用西门塔尔牛育种实践出发,确定了适应当前中国肉用西门塔尔牛的育种目标性状和选择性状。采用差额法计算出各目标性状的边际效益,并通过各目标性状表型值的遗传标准差校正边际效益,得到相应育种目标性状的经济权重。结果表明,中国肉用西门塔尔牛近期的育种目标性状主要包括生长发育性状（断奶重、育肥期日增重、18月龄体重）、胴体性状（胴体品质、屠宰率、净肉率）及繁殖性状（初产年龄、产犊间隔和留群时间）。在现有市场和生产条件下,上述育种目标性状的边际效益分别为17.93元/kg、16.2元/kg、7.17元/kg、297.99元/级、497.82元/%、594.46元/%、-3.62元/d、-26.55元/d、232.75元/y,3类性状中生长发育性状、胴体性状及繁殖性状的经济权重之比为31.49%：15.86%：52.65%,约为2：1：3,繁殖性状占总经济权重最高,其次是生长发育性状和胴体性状。综上所述,在中国肉用西门塔尔牛育种过程中,繁殖性状具有最重要的地位,需加强繁殖性状的选择力度。 相似文献
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繁殖性状是牛（Bos taurus）重要的经济性状,与生产成本、经济效益密切相关。繁殖相关的主要性状包含精液品质、卵泡发生、排卵、胚胎发育、产犊难易、产犊间隔等,其表现通常受到基因的严格调控。对繁殖性状的重要基因功能深入挖掘和筛选对于牛的改良和选育、提高生产性能、节约生产成本至关重要。文章介绍了国内外关于牛繁殖性状基因的研究进展,如促黄体素受体（luteinizing hormone receptor,LHR）及牛精子鞭毛2（sperm flagella 2,SPEF2）与精液品质相关,促性腺激素释放激素（gonadotropin-releasing hormone,GnRH）、促卵泡素（follicle-stimulating hormone,FSH）、促黄体激素（luteinizing hormone,LH）及抗缪勒氏管激素（anti-Müllerian hormone,AMH）、骨形态发生蛋白15（bone morphogenetic protein 15,BMP15）、生长分化因子9（growth differentiation factor 9,GDF9）与卵泡发生、排卵相关,JY-1、尾型同源框2（caudal type homeobox 2,CDX2）及冠毛素2（pappalysin 2,PAPP-A2）与早期胚胎发育及产犊难易相关,唾液酸结合Ig样凝集素5（sialic acid binding Ig like lectin 5,SIGLEC5）、CXC基序趋化因子受体1（C-X-C motif chemokine receptor 1,CXCR1）及叉头转录因子O1（forkhead box O1,FoxO1）与产犊间隔相关,作者通过综述以上重要繁殖性状相关基因的研究,介绍了这些繁殖性状重要基因对牛生产性能的影响,以期为牛繁殖性状相关调控基因的研究提供参考依据。 相似文献
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牛基因组计划的完成,为牛的育种提供了极其重要的遗传信息,使得科学家在基因组水平进行选择成为可能。从肉牛生长性状的数量性状基因座（quantitative trait loci,QTL）、肉质性状的QTL、繁殖性状的QTL以及抗病性状的QTL4个方面进行综述,以期为肉牛的育种研究提供参考。 相似文献
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牛基因组计划的完成,为牛的育种提供了极其重要的遗传信息,使得科学家在基因组水平进行选择成为可能.从肉牛生长性状的数量性状基因座(quantitative trait loci,QTL)、肉质性状的QTL、繁殖性状的QTL以及抗病性状的QTL4个方面进行综述,以期为肉牛的育种研究提供参考. 相似文献
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本研究以1986年中国自主培育兼用牛新品种--三河牛,在内蒙古海拉尔谢尔塔拉种牛场核心群5 257头1998-2012年20 949条繁殖记录为研究材料,以青年牛首次妊娠日龄、青年牛首次产犊日龄、成母牛妊娠期、成母牛空怀期、产犊间隔为研究对象,用SAS 9.13、DMU软件对数据进行处理,采用AI-REML结合EM算法并配合多性状动物模型对各性状影响因素方差组分进行估计,估算出各性状遗传力,并利用各性状育种值分析其遗传趋势.结果显示,青年牛首次妊娠日龄、青年牛首次产犊日龄、成母牛妊娠期、成母牛空怀期、产犊间隔遗传力分别为0.0552、0.0638、0.0527、0.1096、0.0844,繁殖性状除成母牛空怀期遗传力为0.1096外,其余均小于0.1,属于低遗传力性状.青年牛首次妊娠日龄、青年牛首次产犊日龄、成母牛妊娠期、成母牛空怀期、产犊间隔育种值遗传趋势总体上无明显下降趋势,三河牛繁殖性能保持良好.该试验结果为三河牛优化育种方案、提高选种准确性提供重要理论依据. 相似文献
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各国奶牛群体的选育目标建立之后,选育目标一直在不断发展,选择指数中性状的组成、定义和权重等都在不断变化。奶牛的选育是从关注产奶性能而开始,随后增加了体型外貌性状。由于奶牛的健康和繁殖问题的增加以及社会对动物福利的不断关注,20世纪末,世界范围内平衡育种理念在奶牛育种中逐渐形成,一些重要的功能性状加入各国的选择指数中;进入21世纪后,随着奶牛养殖业和社会的发展,育种家们开始关注和研究更多的性状,部分新性状已经开始在育种实践中选育应用。本文通过整理奶牛育种中有关新性状的研究并收集各国奶牛选育方案中的相关信息,综述了近十年奶业发达国家在奶牛遗传选育中正在研究或已经开始应用的新性状,并将这些新性状分为生产效率相关的新性状、应对环境挑战的新性状、健康福利相关的新性状、产品和加工相关的新性状及管理相关的新性状五大类,总结了这些性状的选育背景、定义方法、遗传基础和选育应用情况等,最后还总结了奶牛育种中新性状的研究应用过程,以期为我国奶牛遗传育种研究和育种目标完善提供一定的借鉴。 相似文献
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Ilatsia ED Roessler R Kahi AK Piepho HP Zárate V 《Tropical animal health and production》2012,44(3):519-530
The Sahiwal breed has been used for upgrading the East African Zebu (EAZ) for improved milk production and growth performance
in the southern rangelands of Kenya. Main users of this breed are Maasai pastoralists. Until now, there has been no deliberate
effort to understand why these pastoralists specifically prefer to keep Sahiwal genetic resources as well as which traits
are considered important by them and what is the underlying reason for this. However, this information is regarded vital for
further development of the breed. A survey was conducted between May and October 2009 among Maasai pastoralists in Kajiado
and Narok counties in the Southern part of Kenya, and private ranches and government farms to identify production objectives
and breeding goals of Sahiwal cattle producers. Sahiwal genetic resources were mainly kept for domestic milk production and
for revenue generation through milk sales and live animals. To a limited extent, they were kept for breeding and also for
multiple objectives that included insurance against risks and social functions. Production aims were influenced to varying
extents by various household and farmer characteristics. Sahiwal cattle and their crosses were generally perceived to be better
with respect to productive traits and fertility traits when compared to the EAZ. However, the EAZ was rated higher with respect
to adaptation traits. The breeding objective traits of primary importance were high milk yield and big body size, good reproductive
efficiency and relatively good adaptation to local production conditions. Performance and functional traits are important
breeding goals that play a major role in fulfilling the multiple production objectives. This forms the basis for the optimisation
of a breeding programme for sustainable utilisation to meet the needs of Sahiwal cattle producers. 相似文献
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在分子生物学技术不断发展和完善的情况下,分子育种技术在肉牛新品种培育过程中越来越受到重视。DNA标记辅助选择是最常用的分子育种技术,详尽概述了DNA标记辅助选择对于遗传力低的性状如肉质性状和屠宰性状等的改良效率是传统育种方法的几倍、甚至几十倍,将在牛品种培育中发挥显著的促进作用,提高传统育种效率,缩短育种年限,辅助选育出产肉量高、肉品质量优的肉牛品种。 相似文献
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Economic values of growth and carcass traits in Japanese beef cattle for production systems with various types of integration of levels/ stages (cow-calf and feedlot segments and the integrated system) and production circumstances (including 20% higher genetic levels of the traits, management, and economic alternatives) were used to examine responses to selection. Discounted economic values with interest rates of 0, 4.2 (Japanese average), and 8.4% were obtained to investigate the effect of discounting on selection efficiency. Traits considered were daily gain in the feedlot, marbling score, birth weight, weaning weight, and mature weight. The effects of discounting were small. Correlated responses to selection were not always economically favorable for all situations. Selecting bulls for the base situation (i.e., the typical biological and economic conditions for the production of Japanese Black cattle) resulted in negative genetic changes in weaning weight and mature weight in the feedlot segment. Higher genetic levels of daily gain and weaning weight affected efficiency of selection. Although effects of management and economic alternatives on responses to selection were generally small, lighter market weight influenced responses to selection. The results indicate that predicted correlated responses to selection are sensitive to production systems and some production circumstances. 相似文献
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The production of transgenic farm animals(e.g., cattle) via genome engineering for the gain or loss of gene functions is an important undertaking. In the initial stages of genome engineering, DNA micro-injection into one-cell stage embryos(zygotes) followed by embryo transfer into a recipient was performed because of the ease of the procedure.However, as this approach resulted in severe mosaicism and has a low efficiency, it is not typically employed in the cattle as priority, unlike in mice. To overcome the above issue with micro-injection in cattle, somatic cell nuclear transfer(SCNT) was introduced and successfully used to produce cloned livestock. The application of SCNT for the production of transgenic livestock represents a significant advancement, but its development speed is relatively slow because of abnormal reprogramming and low gene targeting efficiency. Recent genome editing technologies(e.g.,ZFN, TALEN, and CRISPR-Cas9) have been rapidly adapted for applications in cattle and great results have been achieved in several fields such as disease models and bioreactors. In the future, genome engineering technologies wil accelerate our understanding of genetic traits in bovine and wil be readily adapted for bio-medical applications in cattle. 相似文献
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MC Lucy 《New Zealand veterinary journal》2013,61(6):406-415
Dairy cattle have traditionally been selected for their ability to produce milk and milk components. The traditional single-minded approach to selection of dairy cattle has now changed and secondary traits are being included in selection indices by decreasing the emphasis on production. Greater emphasis on non-production traits reflects the industry's desire for functional dairy cattle. Six broad categories of non-lactational traits are discussed in this review. They are: type; growth, body size and composition; efficiency of feed utilisation; disease resistance, e.g. udder health as measured by somatic cell score; reproduction; and management. Most of these traits can be found within selection indices worldwide, although relative emphasis varies. The non-lactational traits mentioned above are quantitative, meaning that the phenotype in the whole animal represents the sum of lesser traits that cannot be easily measured. The physiological mechanisms that underlie quantitative traits are extremely complex. Genetic selection can be applied to quantitative traits but it is difficult to link successful genetic selection with the underlying physiological mechanisms. The importance that the bovine genome sequence will play in the future of the genetics of dairy cattle cannot be understated. Completing the bovine genome sequence is the first step towards modernising our approach to the genetics of dairy cattle. Finding genes in the genome is difficult and scanning billions of base pairs of DNA is an imperfect task. The function of most genes is either unknown or incompletely understood. Combining all of the information into a useable format is known as bioinformatics. At the present time, our capacity to generate information is great but our capacity to understand the information is small. The important information resides within subtle changes in gene expression and within the cumulative effect that these have. Traditional methods of genetic selection in dairy cattle will be used for the foreseeable future. Most non-lactational traits are heritable and will be included in selection indices if the traits have value. The long-term prognosis for genome science is good but advances will take time. Genetic selection in the genome era will be different because DNA sequence analysis may replace traditional methods of genetic selection. 相似文献
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Lucy MC 《New Zealand veterinary journal》2005,53(6):406-415
Dairy cattle have traditionally been selected for their ability to produce milk and milk components. The traditional single-minded approach to selection of dairy cattle has now changed and secondary traits are being included in selection indices by decreasing the emphasis on production. Greater emphasis on non-production traits reflects the industry's desire for functional dairy cattle. Six broad categories of non-lactational traits are discussed in this review. They are: type; growth, body size and composition; efficiency of feed utilisation; disease resistance, e.g. udder health as measured by somatic cell score; reproduction; and management. Most of these traits can be found within selection indices worldwide, although relative emphasis varies. The non-lactational traits mentioned above are quantitative, meaning that the phenotype in the whole animal represents the sum of lesser traits that cannot be easily measured. The physiological mechanisms that underlie quantitative traits are extremely complex. Genetic selection can be applied to quantitative traits but it is difficult to link successful genetic selection with the underlying physiological mechanisms. The importance that the bovine genome sequence will play in the future of the genetics of dairy cattle cannot be understated. Completing the bovine genome sequence is the first step towards modernising our approach to the genetics of dairy cattle. Finding genes in the genome is difficult and scanning billions of base pairs of DNA is an imperfect task. The function of most genes is either unknown or incompletely understood. Combining all of the information into a useable format is known as bioinformatics. At the present time, our capacity to generate information is great but our capacity to understand the information is small. The important information resides within subtle changes in gene expression and within the cumulative effect that these have. Traditional methods of genetic selection in dairy cattle will be used for the foreseeable future. Most non-lactational traits are heritable and will be included in selection indices if the traits have value. The long-term prognosis for genome science is good but advances will take time. Genetic selection in the genome era will be different because DNA sequence analysis may replace traditional methods of genetic selection. 相似文献
20.
H. Khatib I. Zaitoun Y.M. Chang C. Maltecca & P. Boettcher 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(1):26-28
In dairy cattle, many studies have reported quantitative trait loci (QTL) on the centromeric end of chromosome 14 that affect milk production traits. One of the candidate genes in this QTL region – thyroglobulin (TG) – was previously found to be significantly associated with marbling in beef cattle. Thus, based on QTL studies in dairy cattle and because of possible effects of this gene on fat metabolism, we investigated the association of TG with milk yield and composition in Holstein dairy cattle. A total of 1279 bulls from the Cooperative Dairy DNA Repository Holstein population were genotyped for a single nucleotide polymorphism in TG used previously in beef cattle studies. Analysis of 29 sire families showed no significant association between TG variants and milk production traits. Within‐sire family analysis suggests that TG is neither the responsible gene nor a genetic marker in association with milk production traits. 相似文献