Abstract. Title of the paper: Effectiveness of genetic evaluation with transformed data by using dam-daughter pairs of Japanese quails
In estimation of variance components with REML it has been assumed that the data were normally distributed. Egg production traits of poultry have been shown to exhibit markedly non-normal distributions. In this study, six traits from an unselected quail line were analysed. The original data were transformed using the well-established power transformation to approach normality. The genetic evaluation was carried out with a multipletrait animal model, based on transformed and untransformed data, respectively. Two traits of laying performance, of egg weight and body weight were analysed simultaneously. To compare the efficiency of breeding values the method of simulated selection with biological data (dam-daughter pairs) was used. To select the dams with intensities between 10% and 90% we used individual records and BLUP-breeding values, estimated with transformed and untransformed data. The response of such a selection was estimated using the corresponding daughter records. Only for the trait laying Performance up to 200 days of life we could indicate an advantage of the transformation. It was shown, that by changing from one trait to multiple-trait genetic evaluation non-normality could be compensate. For 10% intensity the selection for individual laying performance provided an unexpected high response in comparing with the BLUP-method.