Effect of Route of Newcastle Disease Vaccination on the Incidence of Airsacculitis in Chickens Infected with Mycoplasma synoviae

In two separate experiments, broiler-type chickens were vaccinated at 11 days old with either the B-1 or LaSota strain of Newcastle disease virus (NDV) by aerosol, drinking water, or eyedrop and simultaneously infected with Mycoplasma synoviae (MS). The MS-infected and aerosol-vaccinated chickens had the highest mean lesion scores for airsacculitis. The aerosol-vaccinated groups had the highest hemagglutination-inhibition titers against NDV. Infection with MS had no effect on antibody titers against NDV, and there were no consistent effects on weight gains.