Serological Evaluation Of Live Avian Infectious Bronchitis 793/B.08Ir Vaccine In Controlled Conditions

Infectious bronchitis is an extremely contagious viral disease and causes the major health problems of the poultry industry in most countries of the world. The incidence of continuous genetic and antigenic changes in infectious bronchitis viruses challenges the bird's immune responses. Therefore, a vaccine to prevent the disease in young chickens may effective when formulated with circulating serotype. In case, live infectious bronchitis 793B/08IR was developed in Razi Institute at laboratory scale. The potency of the vaccine was evaluated in commercial broiler chickens in controlled conditions. Two hundred and fifty one-day-old Ross-308 chickens were divided into the four treatment groups and one control group (n=50). The two treatment groups were received 793B/08IR vaccine and other groups received an imported one via eye drop method. The booster was administrated three weeks post vaccinations. Blood samples were collected from chickens in each group before vaccination and at intervals of two-week. The potency of 793B/08IR vaccine was evaluated using ELISA and serum neutralization assays and compared with an imported vaccine. The neutralizing index data and increase in serum antibody titer in treatment chicken groups indicated that live infectious bronchitis 793B/08IR has proper potency against the disease.