Bayesian analysis of genetic parameters for humoral immune responses and residual feed intake traits in Japanese quail

The aim of this study was to estimate genetic parameters of humoral immune responses (antibody titers against sheep red blood cells (SRBC) and Newcastle Disease Virus (NDV)) and residual feed intake from 20 to 45 days of age in Japanese quail. For this purpose, a total of 2492 records of residual feed intake traits and 5238 records of immune traits were used. The analyses of Genetic parameters of traits were estimated through single and bivariate animal models via Gibbs sampling method. Heritability estimates of total antibody titer (AbT), titer of immunoglobulin Y (IgY), titer of immunoglobulin M (IgM) and titer of immunoglobulin F (IgF) against SRBC were 0.08, 0.14, 0.02 and 0.24, respectively, however, heritability of antibody titer against NDV was lower than estimated of SRBC antigen (h2= 0.05). heritability of RFI in different ages were in ranges of 0.04 to 0.07. genetic correlations estimate between total antibody and IgY were positive and high and was 0.92. The negative genetic correlations were related to IgM with RFI and genetic correlations estimates between RFI and other immunoglobulins (IgY, AbT, IgF) and NDV were positive. As a conclusion, selection for IgF due to its heritability (0.24) and negative genetic correlation (-0.23) with RFI, cause improve in RFI and reduce costs, related mainly to feeding and selecting of animals with phenotyping. On the other hand, due to moderate to high positive genetic correlations (0.34-0.80) were found between IgF and other immunoglobulins, selection of it didn’t lead to decline of humoral immune responses in quail.