Effects of Vitamin E and C Supplementation on Performance and Immune Response of Broiler Chicks

In order to study the effect of different levels of dietary vitamin E (0, 50,75,IU kg 1 diets)and L-Ascorbic Acid (0,500 and 1000ppm in drinking water) on performance, immune response and some blood parameters, 432 male commercial broilers were allocated to 9 treatments with 4 replications (12 broilers in each) for 42 days (starter, 0-21day, grower, 2-42 day) in factorial arrangement (3 3) based on completely randomized design. Immunity was assessed as antibody production to Infectious Bronchitis Virus (IBV), Newcastle Disease Virus (NDV) and Sheep Red Blood Cell (SRBC). Chickens were inoculated (18day) intramuscular with 0.5 mL of 5% SRBC. The injection with SRBC was repeated 12 day later. Performance (0-21day)was not influenced by Vitamin E (VE). Daily weight gain (22-42day) was improved in chicks fed diets with supplemented 75 IUkg 1 VE. Lymphoid organ weights and antibody titer for primary and secondary responses to SRBC were increased by 50 IU kg 1 VE. Humoral immunologic response showed that antibody titer to NDV and IBV were highest (p< 0.05) in groups receiving 75 IU kg 1 diet VE. Adding 1000 ppm Vitamin C (VC) in drinking water significantly increased (p< 0.05) antibody responses to SRBC, daily weight gain (22-42day) and body weight gain in 42day. Secondary responses to SRBC, antibody titer to NDV and IBV were improved (p< 0.05) by supplemented 500 ppm VC in drinking water. Overall, the results of this experiment showed that VE and VC supplemental, improved some of performance parameters and humoral immune response in broiler chicks, respectively. This data suggest that optimum growth and humoral immune response may be achieved at supplemental level of VE of 50 IU kg 1 and VC at 500 ppm.