These are neoplastic skin lesions commonly reported in older animals following prolonged exposure of skin to ultraviolet radiation. Squamous cell carcinomas are commonly found on the eye and these are described separately under eye cancer. Cancer sesions are also found on elsewhere on the body including the vulva, perineum, nose, lips and ears, and on the teats and udder (goats and dairy cattle).
Lesions start as thickened areas of reddened, flaking skin that later become ulcerated, necrotic, bleeding masses. Flystrike is a common complication. Body condition is lost quickly once ulceration occurs. Scabby mouth lesions are the main differential diagnosis. Laboratory confirmation requires biopsy specimen collected in buffered formalin for histology.
Animals with noticeable lesion should be excluded form the export process. If detected during export they may be euthanased or salvage slaughtered without delay.
Special attention should be paid to ensuring affected animals are screened out during selection. Lesions are easily missed when animals are grouped hence a systematic inspection method is required.