Submitted to: American Association of Avian Pathologists
Publication Type: Abstract only
Publication Acceptance Date: 12/30/2009
Publication Date: 8/4/2010
Citation: Miller, P.J., Susta, L., Brown, C.C., Decanini, E.L., Absalon, A.E., Afonso, C.L. 2010. Levels of humoral antibodies induced by different inactivated vaccines correlate with egg production in commercial layers challenged with virulent Newcastle disease virus [abstract]. In: Proceedings of the American Association of Avian Pathologists Annual Meeting, July 31-August 04, 2010, Atlanta, Georgia. paper #9300. Interpretive Summary:
Technical Abstract: To evaluate the relationship between humoral antibodies from homologous and heterologous vaccines and egg production, twenty-two week-old commercial layers previously vaccinated with four live B1 vaccines were boosted with two different inactivated Newcastle disease virus (NDV) vaccines, a virulent strain, CA02, or a strain of low-virulence, LaSota, and compared to a control group. Three weeks later, serum was collect for hemagglutination-inhibition (HI) assays and the birds were challenged with the CA02 strain, via eye drop and nasal instillation. Serum for HI assay was taken before termination. The sham-boosted birds had a significant decrease in egg production in comparison to birds that were not challenged, or to birds that were boosted with the two different NDV vaccines. A slight decrease in egg production was observed in the LaSota-boosted birds (heterologous) in comparison to the CA02 boosted (homologous), or the non challenged animals.