Assessment of the Immunogenic Potential of the Intermediate Infectious Bursal Disease Vaccine Virus (D 78) in Broiler Chicks

Abstract: The immunogenicity of the intermediate infectious bursal disease (IBD) vaccine virus (D-78), which commonly used in Sudan, was determined in broiler chicks in this study. The vaccine was employed via three routes of application namely aerosol, intranasal and drinking water. Both agar gel precipitation test (AGPT) and an indirect enzyme linked immunosorbent assay (ELISA) were used to detect the levels of antibody (Ab) responses in sera of vaccinated chicks. The results obtained showed that higher (P>0.05) levels of Abs were noted when the vaccine administered via aerosol route as compared to the intranasal and drinking water. The variation in the Ab levels among the chicks vaccinated with either the intranasal and drinking water using both tests was not significant ((P< 0.05). Following challenge of vaccinated chicks, the protection rates noted are correlated to the levels of Abs elicited. In conclusion, to achieve higher and protective immune status in chicks is recommended to apply the intermediate IBDV (D78) vaccine strain in broiler chicks via the aerosol route. AGPT can be used as a rapid qualitative test to determine the vaccine take among the chicks whereas ELISA should be used quantitatively to determine the levels of Ab responses in vaccinated chicks