The present study was carried out at the Department of Poultry and Fish Production, Faculty of Agriculture, Shibin El-kom, Menoufia University. The experiments were extended from Nov., 2017 to Feb., 2019, in order to determine the concentration of immunoglobulin G (IgG) and investigate its relation to some blood constituents and some productive traits in chickens:
The most important results can be summarized in the following points:-
1. The high immune response group (HR) had the highest IgG concentration (13.68  0.339) mg/dl as compared with both of control (10.11  0.362) mg/dl and the group low IgG (7.20  0.339) mg/dl ones. The statistical differences among groups were highly significant (p≤0.01)
2. The high immunity group achieved the highest fertility rate, hatchability rate, livability and body weight at sexual maturity (p≤0.01) as compared with (Control) and the low immunity group.
3. There was a positive relationship between the immune response to SRBC and hemoglobin concentration, hematocrit percentage, red blood cell counts, white blood cell count, total plasma protein concentration, albumin and globulin concentration.
4. In general, the present results concluded that a complex relationship between immunoglobulin G and immunological and hematological traits of the chickens. The injection of SRBC as a natural antigen induced superior values of