The aim of this study was to investigate macroscopic and microscopic changes induced by avian encephalomyelitis virus (AEV) in goose embryos. One hundred and eighty embryonated goose eggs were used for this purpose. One hundred and twenty five of these eggs were infected and fifty five of them were used as a control group. Twelve-day-old embryos were inoculated in yolk sac with 0,1 ml viral suspension ( AEV–Van Roekel strain, EID50 10¯³).

Such macroscopic findings in embryos as stunting, hydrocephalus, torticollis, deformities in feet and knee joints, twisting in fingers were the main findings observed. Mainly the microscopic changes peculiar to the infection was observed in the central nervous system. These findings included oedema, vascular proliferation, gliosis, neuronal degeneration, and necrosis. In the skeletal muscles, degeneration, necrosis, dystrophy and sarcolemmal proliferation were observed.