Immune response in broiler chicks inoculated with chicken embryo liver cell culture passaged inclusion body hepatitis virus

With a view to assess protection and humoral immune response, 10 days old broiler chicks were infected with chick embryo liver cell culture propagated inclusion body hepatitis virus. The virus was passaged up to 50^th passage levels. The protection study showed 20% and 40% survival rate against the 40^th and 50^th passage levels of the virus, respectively in broiler chicks. The humoral immune response in broilers, as assessed by ELISA, showed 178±2.14 and 190±1.89 titres at 21 day of inoculation with 40^th and 50^th passage levels respectively. However, after 7 day of challenge, the titres observed were 192±2.86 and 196±3.43, respectively. The results indicated that the virus was not fully attenuated and hence did not provide much protection.