Birdfolio. Photos du journal - Africa Geographic Birds. Psittacine beak and feather disease. Sulphur-crested Cockatoo with psittacine beak and feather disease; feather loss and distorted beak growth are characteristic.
Psittacine beak and feather disease is a viral disease affecting all Old World and New World Parrots ( Psittacini , Hookbills ). The virus belongs to the family Circoviridae . It attacks the feather follicles and the beak and claw matrices of the bird, causing progressive feather, claw and beak malformation and necrosis.