Occurrence: Worldwide. Species affected: Chicken. Age affected: Young birds, 12-28 days.

Causes: Circo virus of 19-24 nm in diameter.

Effects: 8-10 day incubation period. Anaemia, weight depression and up to 60% mortality can occur. Bluish discolouration of the wing can also occur (Blue wing disease). Immunosuppression, causing often secondary problems (eg Marek’s).

CAV is a circovirus of 19-24 nm in diameter. It causes acut...