Quelles sont les relations génétiques entre des caractères mesurés sur des animaux purs ou croisés issus de Piétrain ?

Abstract

In pig breeding schemes, the traits of interest are measured in the grandparent or parent populations on purebred animals. However, the progress in these pure breeds should be expressed in the crossbred offspring. It is generally expected that the genetic relationships between traits measured on purebred and crossbred animals are high for growth traits and body composition. The purpose of the study was to estimate the genetic correlations between performances recorded in pure and crossed animals on a large number of traits related to production, quality, welfare and health, i.e. growth rate, carcass composition, meat quality including boar taint, sex hormones, blood parameters, bodily injury and leg weakness. About 1,600 animals were included in the study, either purebred Piétrain or crossbred Piétrain x Large White. For the majority of production traits such as growth and carcass composition, genetic correlations between purebred and crossbred were close to 1 (between 0.7 and 1, with a standard error between 0.05 and 0.20). Some traits had lower correlation parameters such as the number of leukocytes (rg = 0.5 ± 0.30) or the number of injuries at the beginning of fattening (rg = -0.14 ± 0.40)