Two dogs with metabolic epidermal necrosis had hyperkeratosis of the footpads accompanied by erythematous, erosive and crusting lesions affecting the muzzle, external genitalia, perineum and periocular regions. Histopathological examination of skin biopsies revealed a superficial hydropic dermatitis with marked parakeratosis. Both dogs had high plasma activities of alkaline phosphatase and alanine aminotransferase and high concentrations of glucose, and also a marked hypoaminoacidaemia. Despite these similarities, the cutaneous eruptions were associated with different underlying diseases. One dog had a pancreatic carcinoma which had metastasised widely; the primary tumour and the metastases showed glucagon immunoreactivity on immunocytochemical staining, and the dog's plasma glucagon concentration was markedly greater than that of control dogs. The other dog had diffuse hepatic disease; its plasma glucagon concentration was similar to that of control samples and cirrhosis was identified post mortem. Metabolic epidermal necrosis in dogs is a distinct cutaneous reaction pattern which may be associated with different underlying systemic diseases; however, the pathogenesis of the skin lesions remains unclear.

Atlanto-occipital fusion is a rare bony anomaly due to the failure of the developing arches of the first cervical vertebra to separate from the occiput. It may be associated with compressive myelopathy and must therefore be considered in the differential diagnosis of ataxia in the young animal. This report reviews the embryological development of the region and reports the findings in two cases of fusion in the calf.

An 18-month-old Friesian heifer had several unusual, raised, black, cutaneous plaques, some of which were up to 20 cm in diameter, on its head and neck, limbs, thorax and perineum. There was also generalised lymphadenopathy. A clinical diagnosis of lymphosarcoma (sporadic bovine leukosis) was derived from a fine needle aspiration of a skin lesion. Post mortem and histological examinations confirmed a multicentric lymphosarcoma with widespread infiltration into many of the tissues recognised as predilection sites for this type of tumour. However, in the authors' experience, the presence of tumour masses in the trachea and the right mainstem bronchus was atypical.

Two cases of Sertoli-cell tumour in dogs in which the presenting sign was a partially reducible scrotal swelling are described. In one animal intravenous extension of the tumour had led to varicosity of the testicular vein while lymphatic extension had resulted in the formation of both sublumbar and intrathoracic growths. In the second animal there was massive hydrocoele and some varicosity of the distal testicular vein and there was again lymphatic spread with tumours in the sublumbar lymph nodes and the spleen. Both animals showed changes considered to be evidence of feminisation.