Assessment of Different Newcastle Disease Virus Antigens and Inactivators of Binary Ethylene Amine and Formalin for the Hemagglutination Inhibition Assay

Background and Objectives: Newcastle disease is a severe viral threat to the global poultry industry due to its high prevalence and rapid transmission. Evaluating vaccination timing and effectiveness is crucial, often accomplished through the hemagglutination inhibition (HI) assay. This test relies on the virus's agglutination ability in certain animals, utilizing various inactivated antigens. Our study aimed to assess multiple Newcastle viral antigens ( LaSota, clone, thermo-resistant strain, B۱, and V۴ ) inactivated by binary ethylene amine (BEA) and formalin, seeking the best antigen and inactivator for the HI assay.Materials and Methods: We prepared the different ND antigens include; LaSota, Clone, thermo resistant, B۱, V۴ and the mixture of the antigens then inactivated them using BEA and formalin. The hemagglutination (HA) assay determined mean titers, comparing BEA and formalin inactivation. These antigens were also subjected to the HI test using ۱۱۲ serum samples from different commercial poultry flocks to assess their performance.Results: BEA-inactivated antigens exhibited significantly higher mean titers in the HA assay than formalin-inactivated antigens. In the evaluation of different antigens in the HI test, the mean titer of antigen B۱ followed by clone and LaSota displayed a higher mean titer than others.Conclusion: In conclusion, this study recommends using Hitchner pathotype antigens, specifically the B۱ vaccine, for Newcastle disease HI testing. BEA is the preferred inactivator, preserving antigen structure particularly the structure of hemagglutinin antigen while minimizing risks. These findings can enhance serological testing accuracy, contributing to more effective disease control and prevention in the poultry industry.

کلیدواژه ها:

Newcastle viral antigens ، Serological tests ، Commercial poultry flocks ، Hitchner pathotype ، inactivator