利用SAS估计动物BLUP育种值   总被引：2，自引：0，他引：2  

张元跃 《中国奶牛》2006,(5):20-23

本文简要介绍了BLUP的数学背景、用于BLUP计算的SAS程序模块使用方法和2个计算BLUP的程序示例。  相似文献   

The impact of truncating data on the predictive ability for single‐step genomic best linear unbiased prediction          下载免费PDF全文

Jeremy T. Howard  Tom A. Rathje  Caitlyn E. Bruns  Danielle F. Wilson‐Wells  Stephen D. Kachman  Matthew L. Spangler 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(4):251-262

Simulated and swine industry data sets were utilized to assess the impact of removing older data on the predictive ability of selection candidate estimated breeding values (EBV) when using single‐step genomic best linear unbiased prediction (ssGBLUP). Simulated data included thirty replicates designed to mimic the structure of swine data sets. For the simulated data, varying amounts of data were truncated based on the number of ancestral generations back from the selection candidates. The swine data sets consisted of phenotypic and genotypic records for three traits across two breeds on animals born from 2003 to 2017. Phenotypes and genotypes were iteratively removed 1 year at a time based on the year an animal was born. For the swine data sets, correlations between corrected phenotypes (Cp) and EBV were used to evaluate the predictive ability on young animals born in 2016–2017. In the simulated data set, keeping data two generations back or greater resulted in no statistical difference (p‐value > 0.05) in the reduction in the true breeding value at generation 15 compared to utilizing all available data. Across swine data sets, removing phenotypes from animals born prior to 2011 resulted in a negligible or a slight numerical increase in the correlation between Cp and EBV. Truncating data is a method to alleviate computational issues without negatively impacting the predictive ability of selection candidate EBV.  相似文献   

对中国猪育种工作中若干问题的探讨     

王林云 《畜牧与兽医》2007,39(9):1-4

猪的育种工作实际上是人类对猪在世代延续中的一种干预,已有几千年的历史。在中国,BLUP法选种并不是唯一的选种方法,也不是最好的选种方法。分子遗传标记辅助选择目前多数还在实验室内,应用于生产实际还很不成熟。常规选种仍是中国目前猪育种的重要方法,不可忽视。我国多元化的市场要求有多元化的育种目标,而多元化的育种目标要求有多元化的选种方法。在外种猪中适当引入我国地方猪种的血统是一种较好的育种技术路线。生物体(动物品种)遗传资源的"纯"与"杂"是相对的,从核苷酸序列的角度来看,地球上的生物体都是杂合的,没有2个生物体是完全相同的。一个品种永远处于动态平衡与变化之中。  相似文献   

Comparison of genomic and traditional BLUP-estimated breeding value accuracy and selection response under alternative trait and genomic parameters   总被引：2，自引：1，他引：2  

W.M. Muir 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(6):342-355

Accuracy of prediction of estimated breeding values based on genome-wide markers (GEBV) and selection based on GEBV as compared with traditional Best Linear Unbiased Prediction (BLUP) was examined for a number of alternatives, including low heritability, number of generations of training, marker density, initial distributions, and effective population size (Ne). Results show that the more the generations of data in which both genotypes and phenotypes were collected, termed training generations (TG), the better the accuracy and persistency of accuracy based on GEBV. GEBV excelled for traits of low heritability regardless of initial equilibrium conditions, as opposed to traditional marker-assisted selection, which is not useful for traits of low heritability. Effective population size is critical for populations starting in Hardy-Weinberg equilibrium but not for populations started from mutation-drift equilibrium. In comparison with traditional BLUP, GEBV can exceed the accuracy of BLUP provided enough TG are included. Unfortunately selection rapidly reduces the accuracy of GEBV. In all cases examined, classic BLUP selection exceeds what was possible for GEBV selection. Even still, GEBV could have an advantage over traditional BLUP in cases such as sex-limited traits, traits that are expensive to measure, or can only be measured on relatives. A combined approach, utilizing a mixed model with a second random effect to account for quantitative trait loci in linkage equilibrium (the polygenic effect) was suggested as a way to capitalize on both methodologies.  相似文献   

BLUP法在肉羊育种中的应用研究   总被引：2，自引：0，他引：2  

程胜利  杨博辉  孙晓萍  郎侠  郭宪  曾玉峰  梁春年  郭健 《四川畜牧兽医》2007,34(6):33-34

本文从BLUP(最优线性无偏预测)方法的形成、发展以及在肉羊育种中的应用和今后的发展方向等方面进行了比较详尽的阐述。  相似文献   

EPD估计的原理与应用     

李何  陈文丽  刘学洪 《中国畜牧兽医》2007,34(8):35-40

EPD是在BLUP理论的基础上对种用动物遗传值估计的一种参数。EPD值是估计育种值的一半，它是一个容易理解和应用的种畜遗传传递力的值，能很直观地反映种畜价值在其后代中的体现。EPD主要是用在同一品种中2个不同个体间直接遗传效应的比较，从而预测在同一平均遗传值水平上种用动物未来子女的性能差异。EPD适用于动物的出生、发育、母性性状、屠宰性状以及其它特征性状的估计。EPD广泛应用于肉用种公牛价值的评定。对肉牛重要经济性状EPD估计后，以出版物和（或）计算机网络的方式发布，肉牛生产者根据自己的不同需要选用种牛或精液。作者对EPD的估计原理与应用作较为详细的论述。  相似文献   

基于Web的陕北白绒山羊辅助育种管理系统的设计与实现     

徐东升  屈雷 《家畜生态》2009,(4)

针对陕北白绒山羊多性状选择育种研究处于起步阶段的现状,以动物模型BLUP法为核心的多性状复合育种技术体系为依托,在Windows XP平台下利用ASP技术和SQL Server 2000数据库开发了一套基于Web的陕北白绒山羊辅助育种管理系统-ABMS。该系统能实时地管理分布在不同地域种羊场的生产性能测定信息,并能方便地导入和导出选择性状的育种数据。ABMS在陕北白绒山羊种羊场实际应用中体现了技术先进、易于操作、网络化管理等特点,其推广和应用对实现种羊场育种工作和生产管理的自动化,具有极大的促进作用。  相似文献   

Impact of relationships between test and training animals and among training animals on reliability of genomic prediction          下载免费PDF全文

X. Wu  M.S. Lund  D. Sun  Q. Zhang  G. Su 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(5):366-375

One of the factors affecting the reliability of genomic prediction is the relationship among the animals of interest. This study investigated the reliability of genomic prediction in various scenarios with regard to the relationship between test and training animals, and among animals within the training data set. Different training data sets were generated from EuroGenomics data and a group of Nordic Holstein bulls (born in 2005 and afterwards) as a common test data set. Genomic breeding values were predicted using a genomic best linear unbiased prediction model and a Bayesian mixture model. The results showed that a closer relationship between test and training animals led to a higher reliability of genomic predictions for the test animals, while a closer relationship among training animals resulted in a lower reliability. In addition, the Bayesian mixture model in general led to a slightly higher reliability of genomic prediction, especially for the scenario of distant relationships between training and test animals. Therefore, to prevent a decrease in reliability, constant updates of the training population with animals from more recent generations are required. Moreover, a training population consisting of less‐related animals is favourable for reliability of genomic prediction.  相似文献   

山西瘦肉型猪新品系(SD-Ⅰ系)6月龄体重遗传趋势分析     

刘小军  周忠孝 《中国畜牧杂志》1998,(1)

用混合模型ＢＬＵＰ法对山西瘦肉型猪新品系（ＳＤ Ⅰ系）选育过程中０～４世代４０头公猪的４４７头后裔６月龄体重进行了遗传趋势评估。结果表明：群体平均育种值随世代的增加而增加，说明ＳＤ Ⅰ系猪选育过程中所采取的育种措施是有效的。各世代间环境条件基本一致，且除０世代外，对表型值都有正的效应。继续进行选育，６月龄体重尚有提高的可能。  相似文献   

应用BLUP法估计奶山羊产奶性能的遗传趋势   总被引：3，自引：0，他引：3  

雒鸣峰 《畜牧兽医学报》1989,20(1):30-33

应用最佳线性无偏预测法(BLUP法)估计了西农莎能奶山羊(简称西农羊)群1960～1985年间的遗传趋势(Genetic Trend),结果为这26年间羊群产奶性能的平均遗传趋势等于7.2千克/年,表明过去对这群羊的选育是卓有成效的。  相似文献