Two hundred and Forty day-old chicks were randomly distributed in a completely randomized experimental design with four treatments and three replications of twenty chicks each. Diets prepared without additive as Control (CON) (group1); 0.025% Growth Promoter Concentrate (GPC1) (group2); 0.05% Growth Promoter Concentrate (GPC2) (group3) and 0.1% Growth Promoter Concentrate (GPC3) (group4). Growth promoter concentrate contains MOS, EOs, Vitamins and essential components. Results showed that significant improvement for all antibody titers again Newcastle Disease (ND), Infectious Bursal Disease (IBD) and Avian Influenza (AI). The results of total protein, serum albumin and serum globulin showed no significant difference among the dietary treatments for these parameters. Activities of serum gamma glutamyl transferase (GGT), alanine amino transferase (ALT) and Alkaline phosphatase (ALP) also remained non-significant. It can be concluded that dietary growth promoter concentrate could have a clear positive effect on immune response but could not improve the and serum biochemical parameters; however, there was a slight positive effect on 0.1 % level of inclusion in the diet on serum biochemical parameters
