Avian encephalomyelitis
Purpose of Vaccination: To prevent egg production drops that can occur from AE infection in laying hens. In breeders, to prevent egg transmission of the AE virus to the progeny which can result in neurological disorders and mortality. Broilers are protected by maternal antibody resulting from immunization of breeder flocks, and are not vaccinated.
Calnek 1143 strain: isolated on December 24, 1957 from AE-afflicted chicks obtained from Harco, Horchards, a poultry breeder in eastern Massachusetts. The virus was propagated in embryonated-eggs (yolk-sac route), 6 passages and once in chicks.