Effect of in ovo injection of royal jelly on hatchability, immune response and growth performance of broilers

An experiment was conducted to investigate the effect of in ovo injection of royal jelly on immune response and growth performance in broiler. A total of 400 eggs were used in 5 experimental treatments. For each treatment, four replicates were considered and 20 eggs were used in each replicate. The solutions containing 60% RJ and 80% RJ were prepared by mixing 600 and 800 mg of royal jelly in 100 mL of sterile water, respectively. The treatments included 1) control 2) injection of 0.5 ml sterile water, 3) injection of 0.5 ml of solution containing 60% RJ, 4) injection of 0.5 ml of solution containing 80% RJ, and 5) injection of 0.5 ml pure RJ. The hatched chicks were raised for 42 days with the same basal diet. The results showed that in ovo injection of RJ significantly increased average daily gain and improved feed conversion ratio (P<0.05). In comparison with the control group, in ovo injection of solution containing of 80% and pure RJ significantly increased (P<0.05) IgM concentration and antibody titer in response to sheep blood cell (SRBC) injection but significantly reduced total cholesterol and LDL in serum. The carcass yield, relative weight of internal organs, serum concentration of triglycerides, HDL, calcium, phosphorus, and total protein were not affected by experimental treatments. The results of the current research indicated that in ovo injection of RJ may decrease serum lipid parameters and enhance immunity without showing an adverse effect on the performance of broiler chicken.