At 14, 21 and 28 days post-vaccination
(DPV), the serum IgM response was higher in the
birds that had been systemically immunized with
inactivated vaccine than in the chickens vaccinated
with live attenuated NDV vaccine. However, the IgG
was delayed in chickens that were immunized with
the inactivated vaccine compared to the chickens
immunized with live vaccine.