PHOTO 1: Ulcers are normally a consequence of a serious underlying pathological condition. The epidermis and basement membrane is lost with ulcer formation. There are various potential underlying causes: it may be a hereditary defect that causes an abnormally thin and sensitive skin, it may be caused by infectious or systemic diseases, or by immune-mediated disorders such as hyperadrenocorticism. PHOTO 2: Crusting is formed by dried exudate or secretions adhering to the skin surface. Dried material tends to adhere more tightly to hairy areas than in glabrous skin, causing crust to have the potential to become unusually thick. The nature of crusting can give insight to the underlying cause; for example, honey coloured crust is typically caused by an infectious agent, while dark crusts imply tissue damage or haemorrhage. PHOTOS 3,4: The skin is the most common site of tumour development in the dog, representing more than 30% of tumours. Clinical evaluation of cutaneous tumours is challenging, since the clinical appearance of tumours varies widely. Cutaneous neoplasms originate from various components of the skin, with the majority being of epidermal and ectodermal origin and benign.
REFERENCES: PHOTO 1: Côte, E (ed) 2007, ‘Clinical veterinary advisor : dogs and cats’, Mosby Elsevier, St. Louis, pp. 1108-1110. PHOTO 2: Scott, DW, Miller, WH, Griffin, CE 2001, 'Muller & Kirk’s small animal dermatology', 6th ed., WB Saunders, Philadelphia, p. 94. PHOTOS 3,4: Bettenay, SV & Hargis, AM 2006, ‘Practical veterinary dermatopathology’, Teton NewMedia, Jackson, Wyo, pp. 107-157.
Metadata assigned by Dr. M. van Schoor, Senior Lecturer, Dept. of Companion Animal Clinical Studies