It is common practice in the poultry industry to apply a combination of Marek’s disease (MD) and Infectious Bursal Disease (IBD) vaccines at hatchery level to improve management, cost of vaccination and animal welfare. One of the concerns is whether there is any interference between the vaccines when they are mixed.

This study aimed to assess whether the administration of a next-generation IBD immune complex vaccine (GUMBOHATCH®) interferes with the viability of MD vaccines and their replication in birds when they are combined.