Venezuelan equine encephalomyelitis viral infection of newly hatched chickens and embryonating eggs.

Fewer than 25% of 12-hour-old chicks died after subcutaneous inoculation of 5 strains or intracranial inoculation of 3 strains of Venezuelan equine encephalomyelitis virus. Mortality of embryonating chicken eggs inoculated by the allantoic route decreased from approximately 75% to 35% between 9 and 18 days of incubation, although all 18-day-old embryos died after intraembryonic inoculation. Thus, neither newly hatched chicks nor chicken embryos (unless inoculated intraembryonically) would be of value in safety testing inactivated Venezuelan equine encephalomyelitis viral vaccines.