Interference of Infectious Bronchitis Virus Vaccine with Immune Response induced by Infectious Bursal Disease Virus Vaccine in Broiler Chicks

Abstract

The study was designed to investigate the immunological interference or impact of live attenuated infectious bronchitis disease vaccine with live attenuated infectious bursal disease vaccine in broiler chicks. One hundred and seventy commercial broiler chicks were selected at one day of age, the maternal antibody titer was measured, then chicks divided randomly in to four equal groups; G1 vaccinated with IB and IBD, G2 vaccinated with IB, G3 vaccinated by IBD and G4 (Control group). The results of indirect ELISA revealed significant differences that G1 gave mean values of antibody titer of IBDV lower than G3, no significantly differences of bursa of Fabricius index, the result of lymphocytes count showed a significant differences which was high in G3 and a significant lower in G1, also the heterophils count showed a significant differences, which was high in G1 and significant lower in G3, the microscopically examination of Harderian Gland of G1 and G2 showed few plasma cells infiltration, and severe congestion of the blood vessels with inflammatory cells infiltration and few fibrous connective tissue proliferation, while harderian gland of G3 showed marked lymphocyte and plasma cell infiltration. It is concluded that the (IB) vaccine interfere or has impact on immune response of (IBD) vaccine.