Pass D A, Perry R A
Aust Vet J. 1984 Mar;61(3):69-74. doi: 10.1111/j.1751-0813.1984.tb15520.x.
Psittacine beak and feather disease is characterised by loss of feathers, abnormally shaped feathers and overgrowth and irregularity of the surface of the beak. The disease occurs in a number of psittacine species including the Sulphur-crested Cockatoo, Lovebirds , Budgerigars and Galahs . The abnormal appearance of feathers and beak is due to a dystrophic process within the epidermis of the feather and beak. The process consists of epidermal cell necrosis, epidermal hyperplasia and hyperkeratosis. Many of the feather abnormalities are due to retention of a hyperkeratotic feather sheath. A characteristic microscopic finding is the presence of macrophages containing purple intracytoplasmic inclusions in affected epidermis and feather pulp. The inclusions consist of aggregates of particles 17 to 22 nm in diameter. Similar but smaller inclusions occur in epidermal cells. In addition, non-suppurative inflammation occurs in the feather pulp. The findings are suggestive of a viral infection.
鹦鹉喙羽病的特征是羽毛脱落、羽毛形状异常以及喙表面过度生长和不规则。这种疾病发生在多种鹦鹉物种中，包括硫冠凤头鹦鹉、情侣鹦鹉、虎皮鹦鹉和粉红凤头鹦鹉。羽毛和喙的异常外观是由于羽毛和喙表皮内的营养不良过程所致。该过程包括表皮细胞坏死、表皮增生和角化过度。许多羽毛异常是由于角质化过度的羽毛鞘滞留所致。一个特征性的微观发现是在受影响的表皮和羽毛髓质中存在含有紫色胞质内包涵体的巨噬细胞。这些包涵体由直径为17至22纳米的颗粒聚集体组成。在表皮细胞中也会出现类似但较小的包涵体。此外，羽毛髓质中会发生非化脓性炎症。这些发现提示病毒感染。
