Assessment of Commercial Bivalent Inactivated Newcastle Disease Virus and Infectious Bronchitis Virus Vaccines against Prevalent Isolates in Egypt

El-Dabae, Wahid Hussein; Attya, Hala Mahmoud; Elsayed, Marwa Fathy; Soliman, Reem Ahmed; Zaghlool, Moustafa Ahmed; El-Safty, Mounir Mohamed

doi:10.21608/jvmr.2024.241881.1093

Assessment of Commercial Bivalent Inactivated Newcastle Disease Virus and Infectious Bronchitis Virus Vaccines against Prevalent Isolates in Egypt

Document Type : Original Article

Authors

¹ department of microbiology and immunology, veterinary research institute, national research center

² SPF egg department Central Laboratory for Evaluation of Veterinary Biologics, Agriculture Research Center, Cairo 11381, Egypt

³ SPF department Central Laboratory for Evaluation of Veterinary Biologics, Agriculture Research Center, Cairo 11381, Egypt

⁴ SPF departmentCentral Laboratory for Evaluation of Veterinary Biologics, Agriculture Research Center, Cairo 11381, Egypt

10.21608/jvmr.2024.241881.1093

Abstract

Newcastle disease (NDV) and infectious bronchitis (IB) viruses are the most infectious and serious diseases on poultry flocks Egypt. Several types of bivalent inactivated NDV and IB vaccines are used to prevent and decrease incidence of both viruses but efficacy of these vaccines should be monitored periodically to understand the main causes of those breaks. In the current study nine bivalent inactivated NDV and IB vaccines were randomly selected from different batches during routine work at central laboratory for evaluation of veterinary biologics in 2023. Quality control of nine vaccines was applied according to Egyptian standard regulations for evaluation of veterinary Biologics. Completion of inactivation test of nine vaccines for both NDV and IB viruses revealed negative haemaagglutination test for NDV and normal appearance of embryo of IB virus when inoculation in SPF eggs. Immunization of one week old SPF chickens of nine selected vaccines showed neither clinical signs nor mortalities. Collection of serum samples from all tested vaccines on 3rd and 4^th weeks post vaccination showed variable immune response against NDV using Haemagglutination inhibition test and ELISA test against IB virus. Challenge trial of tested vaccines showed variable percent of protection (50% to 100%). Virus shedding in SPF eggs on 3rd, 5^th, 7^th and 10^th days post challenge revealed significant amount of virus in oropharengeal swabs. This study showed validation of some bivalent inactivated NDV and IB vaccines batches in vaccination programs and invalidation of other batches for use.

Keywords