Canary pox causing high mortality in an aviary.
In an aviary housing 200 six-month-old canaries, 165 became ill and 145 died over 6 weeks from a disease initially characterized by lethargy, ruffled feathers, open-mouth breathing, and death in 2 to 3 days. Proliferative "pox-like" lesions around the eyes and mouth were not seen until the 4th week. At PM examination, initially affected birds had cloudy air sacs and patchy pneumonia. Histologically, the lungs had proliferative necrotizing bronchitis. Birds examined PM later had proliferative skin lesions and intracytoplasmic inclusions typical of poxvirus in the epidermis and airway epithelium. A poxvirus isolated from an organ pool of lung, air sac, liver, and skin of affected birds was identified by electron microscopy.