Role of Harderian gland in immune response of chickens with maternal immunity to vaccine against infectious bronchitis virus

In this study we investigated the role of the Harderian gland in the immune response following vaccination against infectious bronchitis (IB). The experiment was carried out on 100 broiler chicks which were divided into two experimental groups. Experimental group O was vaccinated on the first day of age against infectious bronchitis with vaccine Bronhivet I batches that contain a live attenuated strain H120 and the control group did not get immunized. The experiment lasted 21 days. Blood sera were examined on days 1, 7, 14 and 21 for the presence of specific antibodies against infectious bronchitis (ELISA test). Histological changes were observed in the structure of the Harderian gland in relation to the applied vaccine. This research demonstrated the role of the Harderian gland as a secondary lymphoid organ in broiler vaccination against infectious bronchitis. Maternal antibodies present in the IB had no negative impact on the vaccination of chickens on the first day of age. The vaccine virus partially damaged the Harderian gland.