Occurrence: Worldwide, though not reported in chicks in US. The virus has been isolated from non-symptomatic migratory ducks in the US.
Species affected: Laying chickens, ducks, guinea fowl.
Age affected: Adult.
Causes: Avian adenovirus.
Effects: Incubation period is 7-9 days. Loss of colour in pigmented eggs, thin-shelled, soft- shelled or shell-less eggs and a reduction in production up to 40%. Watery albumin and reduction in egg size. Inappetance, dullness and diarrhoea may occur.