Y. Sanada et al., Electron microscopical observations of psittacine beak and feather diseasein an umbrella cockatoo (Cacatua alba), J VET MED S, 61(9), 1999, pp. 1063-1065
Psittacine beak and feather disease (PBFD) was diagnosed in an umbrella coc
katoo (Cacatua alba) with severe feather dystrophy and loss. Electron micro
scopically, the intranuclear and intracytoplasmic inclusion bodies observed
by light microscopy were composed of viral particles forming paracrystalli
ne arrays, whorls, semicircles or concentric circles. Recovered viral parti
cles from the skin and feather follicle tracts were icosahedral and IS to 2
0 nm in diameter.