应用布拉普法选择南阳公牛的研究(上)     

王勇强  刘孟强  高腾云  王冠立 《郑州牧业工程高等专科学校学报》1992,(2)

应用单性状布拉普(BLUP)育种值及方差组分的约束极大似然估计,评价了9头南阳黄牛种公牛的优劣秩次,估出1.5岁体高、体斜长、胸围、管围及体重的遗传力为0.5297、0.6239、0.3929、0.1242和0.4257,1979～1983年5年间各性状年平均遗传进展分别为0.3009、0.1225、—2.1225、O.0494和1.5514。  相似文献   

山西瘦肉型猪SD-Ⅱ系6月龄体重遗传趋势分析     

袁建霞  曹果清  周忠孝 《黑龙江畜牧兽医》2001,(11):11-12

用混合模型BLUP法对山西瘦肉型猪SD-系选育过程中O～4世代53头公猪的603头后裔6月龄体重进行了遗传趋势评估分析。结果表明，遗传传递力与后代平均表型值的相关及其名次的秩相关均迭极显著水平；遗传趋势、表型趋势和年遗传改进量较高，．且遗传趋势与表型趋势较一致，说明SD-Ⅱ系选育过程中所要取的育种措施是有效的，继续进行选育还有提高的可能。  相似文献   

人工神经网络在作物基因组选择中的应用     

束永俊  吴磊  王丹  郭长虹 《作物学报》2011,37(12):2179-2186

目前, 基因组选择育种主要采用线性模型估计遗传育种值指导作物遗传育种的筛选过程, 但是生物体内的基因以及遗传位点的关系主要是复杂的非线性调控。本研究将人工神经网络技术应用到作物基因组选择育种中, 对现有的作物基因组选择育种模型进行优化, 建立了高效的作物基因组选择预测系统, 并与其他线性回归预测模型进行比较。通过分析小麦的育种数据发现, 基于人工神经网络的遗传育种估计效果优于其他线性回归预测模型, 预测育种值与实际育种值间的相关系数平均值达到0.6636, 相应的岭回归BLUP、贝叶斯线性回归模型和基于系谱信息的贝叶斯回归模型的预测能力分别为0.6422、0.6294和0.6573; 最优的预测效果达到0.8379, 远高于其他2种模型的最优结果。同时, 基于人工神经网络的基因组选择模型的预测效果稳定, 与传统的统计模型相近, 因此, 利用人工神经网络技术建立基因组选择是可行的。  相似文献   

Study on Cashmere Goat Breeding and Production Management System on the Basis of RFID     

WU Tie-cheng  WUDUBALA  HE Yun-mei  LI Yu-rong  ZHAO Cun-fa  MA Yue-jun  LIU Bin  ZHAO Sheng-guo 《中国畜牧兽医》2016,43(3):776-783

In order to meet the requirement of the development of cashmere goat industry,and improve the matching accuracy and scientificity of breeding sheep selection and the production efficiency,it is needed to use information technology and modern breeding theory in cashmere goats accurate management and scientific breeding.Using MVC software design pattern,B/S three-tier network architecture,database,BLUP breeding and other technologies,a cashmere goat breeding and production management systems based on RFID was designed and developed in this study.The system contained information management,breeding analysis,production management,nutrition regulation and benefit analysis and other functional modules.In the system,WOMBAT genetic evaluation software was used in calculating cultivation and inbreeding coefficient,then based on this,the optimal combination parents were choosn;The system was designed for different breeding objectives,such us accelerating advances in genetic improvement of cashmere goat economic traits,and developing the production technology through the joint breeding.Based on cashmere goats individual information,the system could automatically generated recommendations for sheep grading,breeding,selecting and cluster grouping;It could also generat warnings on materials,diet formulation and other control points in production (such as pre-production period,light control for increase cashmere,grazing duration,prevention,feeding and so on),it would provide technical support for "1396" sheep breeding and efficient feeding,thus made cashmere goat breeding and production informationalized,standardized and scientific.  相似文献   

Estimation of total genetic effects for survival time in crossbred laying hens showing cannibalism,using pedigree or genomic information          下载免费PDF全文

P. Bijma  A. Vereijken  E.D. Ellen 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(1):60-68

Mortality of laying hens due to cannibalism is a major problem in the egg‐laying industry. Survival depends on two genetic effects: the direct genetic effect of the individual itself (DGE) and the indirect genetic effects of its group mates (IGE). For hens housed in sire‐family groups, DGE and IGE cannot be estimated using pedigree information, but the combined effect of DGE and IGE is estimated in the total breeding value (TBV). Genomic information provides information on actual genetic relationships between individuals and might be a tool to improve TBV accuracy. We investigated whether genomic information of the sire increased TBV accuracy compared with pedigree information, and we estimated genetic parameters for survival time. A sire model with pedigree information (BLUP) and a sire model with genomic information (ssGBLUP) were used. We used survival time records of 7290 crossbred offspring with intact beaks from four crosses. Cross‐validation was used to compare the models. Using ssGBLUP did not improve TBV accuracy compared with BLUP which is probably due to the limited number of sires available per cross (~50). Genetic parameter estimates were similar for BLUP and ssGBLUP. For both BLUP and ssGBLUP, total heritable variance (T²), expressed as a proportion of phenotypic variance, ranged from 0.03 ± 0.04 to 0.25 ± 0.09. Further research is needed on breeding value estimation for socially affected traits measured on individuals kept in single‐family groups.  相似文献   

Performance of genomic selection under a single-step approach in autochthonous Spanish beef cattle populations          下载免费PDF全文

E.-F. Mouresan  J. Altarriba  C. Moreno  S. Munilla  A. González-Rodríguez  L. Varona 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(4):289-299

This study evaluated different strategies for implementing a single-step genomic selection programme in two autochthonous Spanish beef cattle populations (Pirenaica—Pi and Rubia Gallega—RG). The strategies were compared in terms of accuracy attained under different scenarios by simulating genomic data over the known genealogy. Several genotyping approaches were tested, as well as, other factors like marker density, effective population size, mutation rate and heritability of the trait. The results obtained showed gains in accuracy with respect to pedigree BLUP evaluation in all cases. The greatest benefit was obtained when the candidates to selection had their genotypes included in the evaluation. Moreover, genotyping the individuals with the most accurate predictions maximized the gains but other suboptimal strategies also yielded satisfactory results. Furthermore, the gains in accuracy increased with the marker density reaching a plateau at around 50,000 markers. Likewise, the effective population size and the mutation rate have also shown an effect, both increasing the accuracy with decreasing values of these population parameters. Finally, the results obtained for the RG population showed greater gains compared to the Pi population, probably attributed to the wider implantation of artificial insemination.  相似文献   

Estimation of genetic parameters from pedigreed populations: lessons from analysis of alevin weight in Coho salmon (Oncorhynchus kisutch)     

Víctor Martínez  Roberto Neira  G. A. E. Gall 《Aquaculture (Amsterdam, Netherlands)》1999,180(3-4):223-236

The purpose of the study was to assess the impact of various model structures on REML estimates of variance components using data on alevin weight from two replicate populations from the Genetic Improvement Program for Coho salmon (Chile). Data consisted of 130 d alevin weight from a dams-nested-within-sires mating design over two consecutive generations. Relationship information included direct and collateral relatives but parental individuals lacked records. The construction of a range of animal models considered random effects of direct additive genetic, maternal additive genetic and full-sib family effects as well as the covariance of direct and maternal genetic effects. Fixed effects of year (generation) and spawn date of dams within year were considered and also evaluated. The relative effectiveness of various models in describing the data set were assessed using likelihood ratio tests. The results demonstrated the importance of the correct interpretation of effects in the data set, particularly those effects that can influence the resemblance between relatives. The data structure, as well as the animal model applied, markedly influenced the magnitude of variance component estimates. Models based on year as the only fixed effect did not describe the data nearly as effectively as models containing both year and spawn data of dams within year. Simple models based on animal as the only random effect gave upward biased estimates of additive genetic variance. The most appropriate model for the data set was one based on both year and spawn date as fixed effects, and animal and full-sib family as random effects. The results from models combining maternal genetic and full-sib family effects to exploit the full covariance structure of the data showed that there was confounding between these variance component estimates. The most consistent interpretation of this result was that common environmental effects and non-additive genetic effects were more important sources of variability than maternal genetic effects. The study also demonstrated high variability in parameter estimates for replicate populations.  相似文献   

荷斯坦公牛泌乳量育种值的BLUP评价及分析   总被引：2，自引：0，他引：2  

程郁昕  陈宏权  王治华  许春香 《中国牛业科学》2002,28(6):1-4

以公牛女儿数大于10头为限制因子，建立线性模型yijk=μ hi sj eijk，对安徽荷斯坦公牛泌乳量的育种值进行BLUP评定。分析结果表明：估计育种值排序在前的公牛女儿数并不是最多的，在泌乳量这一生产性状的选择育种上表现优秀的种公牛并没有得到充分利用；对部分种公牛在泌乳量估计育种值中排序与其在体型评定中排序进行比较，有一定的不一致性。  相似文献   

基于B/S模式的肉牛选育评估系统的研究与实现     

景旭  昝林森  黄敬伟  张茜茜  李冰冰 《中国牛业科学》2011,37(2):20-23

[目的]通过对肉牛选育评估方法的研究,基于B/S模式,设计并实现一个肉牛选育评估系统.[方法]研究选用发达国家广泛应用的动物模型BLUP方法作为选育依据,采用MVC(Model View Controller)开发模式,基于浏览器/服务器(Browser/Server,B/S)模式收集牛只的基本资料,从而计算遗传参数,...  相似文献   

中国对虾体重育种值估计的动物模型分析     

张天时  栾生  孔杰  罗坤  田燚  王清印 《海洋水产研究》2008,29(3)

育种值是选种和配种计划制定的基础,其准确性与选择效果密切相关。利用中国对虾2005年21个父系半同胞组共1387个个体体重数据,将家系标记时的平均体重、全同胞组效应等因子组合,建立了4种不同的动物模型,应用BLUP法估计体重育种值。4种模型的估计结果分析表明,家系标记时的平均体重和全同胞家系效应是两个重要影响因子,建立的AFB动物模型比其他模型所估计的结果更准确。AFB动物模型估计中国对虾145d的体重遗传力为0.14±0.076,据此计算育种值并进行模拟留种分析。结果显示,在根据表型值或育种值选种的情况下,育种值选种的留种家系或个体的育种值比表型值选种分别提高50%和80.59%,育种值选择的效率更高。  相似文献