{"id":1546542,"date":"2026-07-24T14:44:45","date_gmt":"2026-07-24T12:44:45","guid":{"rendered":"https:\/\/laboklin.com\/tumour-or-infection-nodular-skin-lesions-in-ornamental-birds\/"},"modified":"2026-07-24T14:44:45","modified_gmt":"2026-07-24T12:44:45","slug":"tumour-or-infection-nodular-skin-lesions-in-ornamental-birds","status":"publish","type":"post","link":"https:\/\/laboklin.com\/fr\/tumour-or-infection-nodular-skin-lesions-in-ornamental-birds\/","title":{"rendered":"Tumour or Infection? Nodular Skin Lesions in Ornamental Birds"},"content":{"rendered":"

[vc_row][vc_column width=\u00a0\u00bb2\/3″][vc_column_text]The skin of birds, as in mammals, is a target organ for lesions of a wide range of aetiologies. If featherless areas are affected, even minor changes are usually noticed at an early stage, whereas processes beneath the plumage often only become apparent at a later stage. The type of housing also plays a role: birds that regularly have closer contact with humans, such as many psittacines (Fig. 1), are examined much more closely than birds kept in flocks without direct human contact.<\/p>\n

Macroscopically, lesions on the beak, eyelids, legs or around the cloaca usually present as plaque-like to nodular changes. Superficial erosions, purulent deposits or bleeding are often observed.<\/p>\n

In feathered areas, however, the first noticeable sign is often locally ruffled plumage, as the underlying mass alters the position of the feathers.<\/p>\n

In principle, neoplastic and non-neoplastic masses can be distinguished; the latter can be further divided into infectious and non-infectious causes.<\/p>\n

However, differentiation based solely on macroscopic appearance is generally not possible, meaning that cytological and histopathological examinations are essential for further diagnosis.<\/p>\n

Fine-needle aspiration is a minimally invasive method and in many cases already provides valuable information about the nature of the lesion.<\/p>\n

However, it should be noted that obtaining diagnostically relevant material can be difficult, particularly in the case of cavernous or very firm masses. In addition, secondary inflammation and bacterial infections can obscure the underlying process. Care must be taken when collecting cells, as cell damage (e.g. due to excessive pressure when spreading the material) or smears that are too thick (i.e. without a monolayer) can impair evaluation. This should be taken into account both when preparing impression smears and when performing aspiration.<\/p>\n

Neoplastic Skin Lesions<\/h2>\n

Neoplastic proliferations can generally be of epithelial or mesenchymal origin or arise from round cells. It should be noted that neoplasms may develop primarily in the skin or occur secondarily as a result of metastasis.<\/p>\n

1.\u00a0\u00a0\u00a0 Epithelial Tumours<\/h4>\n

Sites predisposed to the development of epithelial tumours include the eyelids, oral cavity, legs and uropygial gland. Squamous cell carcinoma is a commonly diagnosed malignant tumour. Even small lesions tend to ulcerate and develop secondary crusting, meaning that an inflammatory process is often initially suspected clinically. Cytological diagnosis can be complicated by these secondary changes. Histologically, however, invasive growth, atypical keratinisation and, where applicable, vascular invasion can be reliably identified (Fig. 2)<\/strong>.<\/p>\n

Benign epithelial neoplasms are often papillomas. These are caused by host-specific papillomaviruses, which lead to wartlike lesions of the skin or mucous membranes. Although these are benign proliferations, their rapid growth can result in mechanical impairment (e.g. in the beak). The gold standard for diagnosis is histopathological examination of the tissue and the identification of basophilic intranuclear viral inclusion bodies.<\/p>\n

In the region of the uropygial gland, hyperplasia and adenomas can occur in addition to malignant neoplasms. Cytologically, it is not possible to differentiate between these latter two changes, as both consist of well-differentiated epithelial cells. Particularly in association with hypovitaminosis A, pronounced keratinisation with hyperplastic epithelial proliferation may also occur[\/vc_column_text][\/vc_column][vc_column width=\u00a0\u00bb1\/3″][vc_column_text]<\/p>\n\n\t\t\t