Isolation of Viruses from 94 Flocks of Fowls with Respiratory Disease

Virological studies were made on 94 flocks of fowls suffering from respiratory disease. Infectious bronchitis virus was detected in 50 flocks by egg inoculation and using tissue culture techniques adenovirus was detected in 41, reovirus in 3 and mycoplasmas in 4 flocks. In addition small 20 nm. particles associated with adenoviruses were seen on 6 occasions and it is believed that they may be adeno-associated parvoviruses. Direct examination of allantoic fluid or tissue cultures using the electron microscope was found to be a quick and efficient method of virus and mycoplasma identification. In addition it demonstrated strains of infectious bronchitis virus which failed to cause dwarfing and allowed the detection of parvoviruses.