Effect of various vaccination programs against Influenza virus on humoralimmune response in broiler chickens

Objectives: In recent years, the H9N2 influenza virus (low pathogen), has caused a lot of economicdamage to the Iranian poultry industry due to reduced production, increased mortality and highvaccination costs. The investigation of avian influenza virus control programs is necessary becauseof the widespread dissemination and the ability of the virus to become a highly pathogenic form.Materials & Methods: In this study, in order to evaluate the effect of various vaccine programagainst H9N2 influenza virus in broiler chicken, chicks were purchased divided intothree 500 chicks groups and in Three separate breeding rooms were placed under the samebreeding conditions and were vaccinated on first (group 1), third (group 2) and seventh (group 3) ofage with bivalent IntervetR Influenza H9N2 and Newcastle disease killed vaccine, respectively. Theblood samples were taken from 24 chicks on the first day and at the end of each week from eachhall separately 24 blood samples were collected. The hemagglutinin inhibition (HI) test wasperformed on serum samples.Results & Conclusion: The results of the HI test were analyzed by ANOVA and Duncan test. Theresults showed that early vaccination against influenza on first and three days of age did not onlylead to increase production, but also decreased antibody titer at the age of 35 and 42 days inCompared to the group that was vaccinated against influenza in seven days of age.

کلیدواژه ها:

avian influenza ، vaccination program ، antibody titer ، Serum ، H9N2