tailieunhanh - Báo cáo khoa hoc:" Comparison between estimation of breeding values and fixed effects using Bayesian and empirical BLUP estimation under selection on parents and missing "

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: Comparison between estimation of breeding values and fixed effects using Bayesian and empirical BLUP estimation under selection on parents and missing | 41 Genet Sei. Evol. 34 2002 41-59 INRA EDP Sciences 2002 DOI gse 2001003 Original article Comparison between estimation of breeding values and fixed effects using Bayesian and empirical BLUP estimation under selection on parents and missing pedigree information Flavio S. Schenkel Lawrence R. Schaeffer Paul J. Boettcher Centre for Genetic Improvement of Livestock Animal and Poultry Science Department University of Guelph Guelph Ontario NIG 2W1 Canada Received 11 December 2000 accepted 2 July 2001 Abstract - Bayesian via Gibbs sampling and empirical BLUP EBLUP estimation of fixed effects and breeding values were compared by simulation. Combinations of two simulation models with or without effect of contemporary group CG three selection schemes random phenotypic and BLUP selection two levels of heritability and and two levels of pedigree information 0 and 15 randomly missing were considered. Populations consisted of 450 animals spread over six discrete generations. An infinitesimal additive genetic animal model was assumed while simulating data. EBLUP and Bayesian estimates of CG effects and breeding values were in all situations essentially the same with respect to Spearman s rank correlation between true and estimated values. Bias and mean square error MSE of EBLUP and Bayesian estimates of CG effects and breeding values showed the same pattern over the range of simulated scenarios. Methods were not biased by phenotypic and BLUP selection when pedigree information was complete albeit MSE of estimated breeding values increased for situations where CG effects were present. Estimation of breeding values by Bayesian and EBLUP was similarly affected by joint effect of phenotypic or BLUP selection and randomly missing pedigree information. For both methods bias and MSE of estimated breeding values and CG effects substantially increased across generations. breeding value selection Bayesian estimation empirical BLUP Gibbs sampling Correspondence and .