Genetic and phenotypic analysis of sexual dimorphism of the humoral immune response in wild and speckled Italian quail strains

The aim of this research was to investigate the immune system responses against sheep red blood cells (SRBC) and Newcastle disease virus (NDV) in two sexes of both wild and Italian speckled quails. To compare phenotypic differences of two sexes for humoral immune responses a one-way analysis was applied, and a simple animal model using the MCMCglmm package of R software was used for genetic analysis, assuming variance components between the two sexes are different. Phenotypic comparison between males and females did not show a significant difference in any of the strains. In both strains, heritability of humoral immunity in males was higher than females. Results indicated that heritability of IgT in males (0.187), and IgY in females (0.177) were higher than other estimates in wild strain. The highest heritability was related to the NDV, which was estimated to be 0.214 and 0.268 in males and females, respectively. Therefore, genetic selection for IgN can be expected to improve the performance of the birds’ humoral immune system. Likewise, according to the higher estimates of immune responses in males, genetic selection of humoral immune responses for IgN, leads to higher genetic progression.