Combined administration of Newcastle Disease and Avian Metapneumovirus live vaccine to one-day-old turkeys: vaccine interaction and protection against virulent AMPV

The combined administration of Newcastle Disease (ND) and Avian metapneumovirus (AMPV) live vaccines in turkey hatcheries is advantageous, but compatibility has not yet been experimentally demonstrated. To investigate any possible interference between the two vaccines, AMPV subtype B live vaccine was given to one-day-old turkeys either alone or in combination with two different ND vaccines of the B1 and VG/GA strains. AMPV and NDV post vaccination shedding and humoral immune response were assessed. Results showed that, following single or combined vaccinations, both AMPV and/or ND vaccine virus were detected in the respiratory tract of all of the birds in all the groups. In addition, birds were protected from virulent AMPV virus challenge and differences in clinical signs between groups vaccinated with AMPV vaccine alone or in combination with ND vaccine were not statistically significant.