In
Ovo Vaccination against Avian Influenza Virus
Subtype H9N2
Saba Rafique1,
Naila Siddique1, Mazhar Qayyum2, Muhammad
Athar Abbas1, Akbar Ali1, Samina Yasmeen1
and Khalid Naeem1*
1National Reference Lab for
Poultry Diseases, Animal Sciences Institute, National Agricultural
Research Centre, Islamabad; 2Department of Zoology, Faculty of Science, PMAS Arid
Agriculture University, Rawalpindi, Pakistan;
*Corresponding author:naeem22@comsats.net.pk
Abstract
Due to the major occurrence of infection by avian
influenza virus (AIV) subtype H9N2 in broilers and broiler breeders at first 2-3
weeks of age in this country, where the virus is endemic since 1999, it has
become necessary to devise new strategies for better protection of chicks at
early age. In ovo vaccination is one
of the approaches for providing neonatal resistance against various infectious
diseases in chickens. The aim of this study was to develop
in ovo vaccine against H9N2 serotype
of AIV. For this purpose a vaccine strain of AIV H9N2 was used to develop both
inactivated and live virus vaccines for experimentally inoculating18- day old
embryos.In addition to this two other
groups of chicken were separately vaccinated with both inactivated oil-emulsion
and live virus vaccines of H9N2 for comparison. The hatched chicks were
monitored for the development of HI antibody response against AIV H9N2. All
these birds were later challenged with field isolate of AIV H9N2.The results indicated that in ovo
live AIV H9N2 vaccine produced higher antibody response at younger age and
showed better protection upon challenge.
Key words:
Avian influenza virus,
Bird flu,
Disease control,
H9N2, In Ovo vaccination