tailieunhanh - Báo cáo khoa hoc:" On the use analysis of animal models in the of selection experiments"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: On the use analysis of animal models in the of selection experiments | Genet. Sei. Evol. 31 1999 135-148 Inra Elsevier Paris 135 Original article On the use of animal models in the analysis of selection experiments Louis Ollivier Station de génétique quantitative et appliquée Institut national de la recherche agronomique 78352 Jouy-en-Josas cedex France Received 25 May 1998 accepted 28 January 1999 Abstract The use of an animal model in the analysis of selection experiments offers the theoretical advantage of accounting for changes occurring in the genetic parameters in the course of the experiments. Explicit estimators of realized heritability lị are derived in this paper for balanced one-generation selection designs. Expressions are given for the expectations and variances of the estimators in relation to the true heritability and for the sensitivity of the estimators to the prior value of heritability. Sensitivity is generally high except for high values of the true heritability and or extremely large family sizes. The uncertainty on heritability may however be taken into account in a context of Bayesian inference which allows a simultaneous estimation of the initial heritability and of the response. On the other hand animal model estimators being dependent on the genetic model assumed may not provide adequate measures of the actual responses. They also tend to overestimate the accuracy of genetic trend evaluations since genetic drift is not properly accounted for. Animal models however provide a way of evaluating the effects of selection and limited population size in long-term selection experiments and thus permit a check on the validity of the underlying infinitesimal additive genetic model. Some examples based on published results of long-term selection experiments on mice are discussed. Inra Elsevier Paris genetic evaluation selection experiment animal model BLUP realized heritability Resume utilisation du modèle animal dans 1 analyse des experiences de selection. L application du modèle animal à 1 analyse des experiences de .