Genome-wide scan for reproductive traits of beef heifers using high density SNP panels

Quantitative Trait Loci (QTL) detection for sexual precocity and fertility of beef heifers was performed by a Bayesian approach and based on performance recorded in French progeny test station of Blonde d’Aquitaine bulls. Heifer oestrus and fertility were observed on about 25 daughters for each of the 158 genotyped bulls. Genotyping was mainly carried out with the Bovine high density BeadChip®. A total of 78 QTL were identified with strong evidence for an effect on sexual precocity. Comparing these results with QTL previously reported in the literature, 2 unknown QTL were identified for sexual precocity among the 7 regions with major evidence for a QTL. Regarding heifer fertility, only 6 QTL were detected, 3 of them matched with previous studies on dairy cattle. Two common QTL regions were identified as playing a strong role on both reproductive traits