Quantitative trait loci for body weight and carcass traits in Japanese quail

Body weight (BW) and carcass traits are complex and important economic traits that may benefit from the implementation of MAS. The objective of the current study was to identify QTL associated with BW and carcass traits in an experimental half-sib cross of Japanese quails selected for BW at 4 weeks of age. Body weight and carcass traits were measured in the F2 population. Total F2 individuals and their parents were genotyped by 6 informative microsatellite markers on chromosomes 1, 2 and 9. Interval mapping was conducted to identify putative QTL. Two QTL for BW at hatch were detected on chromosomes CJA02 and CJA01 at the 1% chromosome wide and the suggestive levels, the significant QTL explained 1.24% of the phenotypic variance. For BW at 4 wk of age three QTL were identified on chromosomes CJA01, CJA02 and CJA09 at the 1% chromosome wide and the suggestive levels, the significant QTL explained 1.21% of the phenotypic variance. A QTL for carcass weight (CW) at 4 wk of age was identified on chromosome CJA01 at the suggestive level. Three QTL for breast weight (BRW) at 4 wk of age were identified on chromosomes CJA02, CJA01 and CJA09 at the 5% chromosome wide and the suggestive levels, the significant QTL explained 1.08% of the phenotypic variance. A QTL for breast percentage (BRP) at 4 wk of age was identified on chromosome CJA02 at the 5% chromosome wide; the significant QTL explained 1.10% of the phenotypic variance. The present study identified chromosome regions harboring significant QTL effecting BW and carcass traits. The results provide a useful reference for further candidate gene research and MAS for BW and carcass traits.