A) live, avirulent vaccine consisting of the three major serotypes (1, 2, and 5) of R anatipestifer

b) A formalin-inactivated cell suspension of the three major serotypes (1, 2, and 5) of R anatipestifer is recommended for preventive immunization on farms where the disease is endemic or epidemic.

Ducklings should not be vaccinated within 21 days of slaughter