tailieunhanh - Báo cáo khoa hoc:" Genetic parameters of beef traits of Limousin and Charolais progeny-tested AI sires"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học thế giới đề tài: Genetic parameters of beef traits of Limousin and Charolais progeny-tested AI sires | Genet. Sei. Evol. 31 1999 465-489 Inra Elsevier Paris 465 Original article Genetic parameters of beef traits of Limousin and Charolais progeny-tested Al sires Marie-Noelle Fouillouxa b Gilles Renanda Jacques Gaillardb Francois Ménissiera a Station de génétique quantitative et appliquée Institut national de la recherche agronomique 78352 Jouy-en-Josas France b Institut de 1 élevage Station de génétique quantitative et appliquée 78352 Jouy-en-Josas France Received 10 November 1998 accepted 3 September 1999 Abstract - Sire selection efficiency depends on the knowledge of accurate genetic parameters. In France artificial insemination Al sires are selected according to their own performances and those of their progeny which are both recorded in test stations. Genetic parameters among progeny traits were estimated using multi-trait REML restricted estimation of maximum likelihood analyses in Charolais and Limousin breeds. The expected decrease in genetic variability algebraically calculated among progeny traits due to the selection of sires was not observed. This selection was not a strict truncation. Heritabilities of traits measured on progeny are moderate for growth traits morphology and live fatness scores from to and slightly higher for dressing percentage and carcass fatness score and respectively . Genetic correlations among progeny traits depended on traits selection programme and breed. Carcass weight and morphology were highly genetically linked to corresponding live traits live weight and conformation respectively . They can therefore be easily improved through indirect selection in contrast to carcass fatness which has only a small genetic correlation with live traits. Inra Elsevier Paris genetic parameters live and carcass traits Charolais and Limousin breeds selection Resume Paramètres génétiques des aptitudes bouchères des taureaux d insemination artificielle Limousins et Charolais contrôlés sur descendance. L efficacite de la selection