Mapping of Quantitative Trait Loci for Immunity Traits by Microsatellite Markers on chromosome 5 in Japanese Quail

Immune traits are very important because of their direct relationship with the growth traits and the economic value of quail breeding. The purpose of this study was to investigate the part of the Japanese quail genome in order to detect QTL affecting on immunity traits using a four-generation crossover design. For this purpose, four strains of A and M Texas, Wild, Italian Speckled and Tuxedo Japanese quails were mated as reciprocal crossed for creating the first generation. Then, another generation, including the second, third and fourth generations were created from the crossing of the first generation hybrid birds. Phenotypic data included traits related humoral immunity of birds, including T, M and Y immunoglobulins. The third and fourth generation parents and all birds from the fourth generation parents were genotyped for three microsatellite markers located on the chromosome 5. QTL analysis was performed by interval mapping based on regression with GridQTL software. Three adjacent QTLs in the middle of chromosome 5 for the three IgT, IgM, and IgY were identified at the positions 13.5, 8.9, and 14.7 cm near to marker GUJ0049, respectively. Therefore, the results showed that there was at least one gene with a major effect on immunity traits adjacent to the marker GUJ0049, and adding the information of the mentioned marker genotypes to the statistical models could improve the accuracy of prediction of breeding values for immunity traits ​​in quail.