EVALUATION OF NEUTRALIZING ANTIBODY ON VACCINATED CHICKEN BY GAMMA IRRADIATED AVIAN INFLUENZA VACCINE SUBTYPE H9N2

Background and Aim:: Avian influenza A subtype H9N2 virus belongs to Orthomyxoviridae family and causes low-pathogenic disease. H9N2 subtype was first reported to have infected turkeys in the United States in 1966 and has been enzootic in Eurasia. In Iran, the H9N2 virus was first isolated from broiler chickens in 1998 in Ghazvin Province and it is the most prevalent subtype of influenza virus in poultry industry in Iran at the present time causing serious economic losses in the poultry industry. The hemagglutinin (HA) antigen is the most important viral glycoprotein for attachment and fusion in virus replication cycle and is highly immunogenic.Methods:Avian Influenza virus (AIV) subtype H9N2 was multiplied on embryonated SPF chicken eggs of 9–11 days. AIV was irradiated by a Nordian model 220 gamma cell instrument at a dose rate of 2.07 Gy/s and activity of 8677 Ci to damage influenza virus genomic RNA to inactivate virus infectivity with 30 kGy gamma radiation. The neutralizing antibody response by hemagglutination inhibition (HI) method was evaluated on vaccinated broiler chickens in three vaccine concentrations (1, 10-1, and 10-2).Results:The result of antibody titers was analyzed by Anova one-way method. The result of antibody titration by HI method was shown inhibition of erythrocyte agglutination by an antigen-antibody reaction was increase significantly for two vaccinated groups (1 and 10 -1 vaccine concentrations) against negative control group (P<0.05).Conclusion:The neutralizing antibody titration was increased after on vaccination broiler chicken by gamma irradiated Avian Influenza vaccine subtype H9N2.

کلیدواژه ها:

Avian Influenza ، Gamma Irradiation ، Hemagglutinin Antigen ، Inactivation ، Hemagglutination Inhibition test ، Broiler Chicken