Effectiveness Of The Pigeon Pox Vaccine On The Chicken Vaccinated With Avian Influenza Vaccine

Evaluation of the effectiveness of pigeon pox (PP) vaccine in improvement the required immunity to avian influenza (AI) virus vaccine in birds and reducing its shedding after challenge was the object of this study.Specific pathogen free chicks were vaccinated with PP and AI in 10 groups at 5 and/or 8 days of age and/or boosted after 35 days then challenged after 28 days with virulent highly pathogenic AI virus local Egyptian field isolate. The development of immune responses to AI haemagglutinine was recorded and also AI virus shedding after challenge.Vaccinated 10 groups induced protective immune responses; especially in the groups which were boosterly vaccinated with PP vaccine. All birds vaccinated and experimentally challenged 28 days later were protected against virulent AI (H5N1); mild clinical signs of infection developed in few number of vaccinated birds. In contrast, all unvaccinated birds died within 72 hours of challenge. Vaccination of chicks with PP and AI vaccines provided good effectiveness of the PP vaccine on the immune response of vaccinated birds with AI vaccine and showed decreasing in shedding after challenge; especially in the groups which take a booster vaccination of PP and AI vaccine. Although eradication still remain the 1st of choice for controlling the AI in the circumstances of a continuing and wide spread outbreak, but also the availability of new designing future vaccination regime by using avipox virus vaccine should be applied.