Quantitative Trait Loci for some of Behavior and Performance Traits on Chromosome 4 of Japanese Quail

The current study was conducted to identify the quantitative trait locus (QTL) for the body weight at age 1, 7, 14, 21 and 28 days and daily gain at age 0-1, 1-2, 2-3 and 3-4 weeks, slighter carcass weight and tonic immobility in Japanese quail. Two divergently lines of wild and white Japanese quail which maintained in the Animal Science Research Center of the Shahid Bahonar University of Kerman was used. Birds in two lines were mated in reciprocal cross for generating F1 generation. The F2 generation was generated by ran-dom mating of F1 birds. The half sib and F2 model analysis of QTL express was used for QTL mapping the measured traits. Total F2 individuals (422 birds), their parents (34 F1 birds) and pure lines (16 birds) were genotyped by 2 informative microsatellite markers on chromosomes 4. On this chromosome, with the half sib model, no significant QTL at the 5%, 1% chromosome wide was detected. But, with the F2 model, a significant QTL at the 5% chromosome wide was identified for body weight (BW) at age 21 and 28 days, carcass weight and daily gain traits during 1-2, 2-3 and 3-4 weeks in 54cM position. The all of identified QTLs explain less of 4% of the phenotypic variance, because the traits of growth are complex traits affected by many loci influencing appetite, feed uptake, nutrient allocation, metabolic rate, physical activity and so forth.