Occurrence: Worldwide. Species affected: All. Age affected: All.

Causes: Avian pox viruses are single, linear double stranded DNA viruses.

Effects: Incubation is from 4-10 days. There are two forms of the disease- cutaneous dry and diphtheritic or wet. Both may present in the same flock. The dry form is manifest as pimples or scabs on the skin (mainly on unfeathered parts of the body). The diphtheritic form shows cankers or yellow lesions in the ...