Comparative Efficacy of Oculonasal and Intranasal Routes of Vaccination in Induction of Immune Response against Newcastle Disease Virus

Vaccination programs to control Newcastle disease include use of low virulent live virus vaccines or inactivated vaccines to induce protective immunity. In order to further characterize the immune response elicited by live virus, we evaluated both cellular and humoral immune response to Newcastle disease virus (NDV) consequent to vaccine application by oculonasal and intranasal routes. Specific antiviral antibodies to NDV were detected as early as 7 days post vaccination (PV). The peak antibody levels were achieved at 2 wk PV and 3 wk PV in chicken vaccinated by oculonasal and intranasal route, respectively. The antibodies persisted upto 7 wk PV albeit low levels. The NDV specific cell mediated immune response (CMI) as detected by lymphocyte proliferation test was induced at 3 wks PV and that persisted upto 7 wk PV in chicken vaccinated by both oculonasal and intranasal route. These results suggest that both oculonasal and intranasal routes of vaccination induce comparable immune responses in chicken vaccinated with lentogenic ND vaccine.