The antibody responses against APMV-3 and NDV by rAPMV-3 or rNDV expressing HA in broilers. The groups of broilers were immunized with 106 TCID50/bird of rNDV/HA or rAPMV-3/HA based on regimen of vaccination for each group mentioned in Table 1 through oculonasal route. Three weeks after prime-immunization and two weeks after boost-immunization the sera were collected from all chickens and the antibodies induced against rAPMV-3 strain Netherlands (A) and rNDV strain LaSota (B) were detected by HI assay. The level of maternally derived antibodies (MDAs) against rAPMV-3 strain Netherlands (C) and rNDV strain LaSota (D) in non-infected broilers also were detected by HI assay. Serum titers are expressed as reciprocals Log2 dilution.