Experimental infection of quail by NDV and its immune response to vaccination

Document Type : Original Article

Authors

1 Faculty of Veterinary Medicine, Benha University, Egypt

2 Veterinary Serum and Vaccine Research Institute, Abassia, Cairo

Abstract

This work aimed to study quail susceptibility to Newcastle disease virus (NDV); their role in disease
transmission and their immune response to ND vaccine. Forty percent (4/10) of quail were susceptible
to experimental infection with virulent NDV with signs of loss of appetite, weakness, diarrhea and
nervous symptoms then death. Chickens group housed in contact with infected quail and chickens group
experimentally infected with NDV were suffering from typical NDV infection 15 days post contact
infection and 3 days post experimental infection, respectively. Post mortem examination of dead birds
revealed hemorrhagic lesions of the intestinal tracts and proventriculus; and NDV was recovered from
tracheal and intestinal samples and identified by HI test using NDV-Specific antiserum. Birds vaccinated
with inactivated NDV vaccine exhibited detectable antibody titers (2 log2) by the 1st week post
vaccination (WPV) to reach their peaks by the 3rd WPV (6 log2 in quails and 7 log2 in chickens). These
antibody titers were able to protect quail and chickens against challenge with virulent NDV recording
100% protection rates in comparison to non-vaccinated birds showing 70% and 100% mortality in quails
and chickens, respectively. Being susceptible for NDV, quail have a role in transmission of NDV to
chickens, so they should be vaccinated for their protection and prevent their role in NDV transmission to
chickens.

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