EVALUATION OF THE IMMUNE RESPONSE OF SOME CHICKEN FARMS TO INFECTIOUS BRONCHITIS VIRUS IN AL-AHSA PROVINCE IN SAUDI ARABIA.

Infectious bronchitis virus (IBV) still to pose great economic losses among chickens of all ages in many parts in the world. Despite the massive application of IBV vaccines in many countries including Saudi Arabia, several outbreaks are still frequently reported. One of the important challenges that hampered the selection of the right vaccine candidates is the identification of the local circulating strain in a certain area. IBV is recently reported in many chickens flocks in the Eastern region of the Kingdom. The major goals of our study were to evaluate the immune status of some chicken farms in Al-Ahsa to IBV. To achieve this goal, total of (368) serum samples from chicken farms from Al-Ahsa region were collected. Our results showing high seroprevelance of IBV in the non-IBV vaccinated chicken farms suggesting their exposure to the natural IBV infection. Meanwhile, we were able to detect a high IBV antibody titers in vaccinated chicken farms suggesting the used vaccines induced detectable IBV antibodies. This suggesting the circulation of novel IBV strains in these chicken farms. The overall results confirm the circulating of novel IBV strains in chicken farms in Al-Ahsa region. Further studies are needed to do molecular characterization of these IBV strains. [ABSTRACT FROM AUTHOR]