A 12-year-old male domestic short-hair cat was presented with a sudden laceration of the lumbar skin. The lumbar skin showed irregular tears and shedding as a large sheet. Histopathological examination of the skin revealed atrophic epidermis with hyperkeratosis, and decreased and fragmented collagen fibers in the dermis. A diagnosis of acquired skin fragility syndrome was consequently made. The present case died of asthenia with an eating disorder due to a large mandibular abscess. Necropsy and histopathological examination revealed that the cat had cholangiohepatitis, membranoproliferative glomerulonephritis, and intestinal villi fibrosis as complications of the skin lesion. Clinical improvement of the skin lesion was found after treatment with a digestive enzyme compound agent administered in consideration of the malabsorption. Therefore, malabsorption might be closely related to the skin lesion of the present case.

Here we describe the clinical and pathological findings of a 15-year-old cat with multiple cutaneous tumors including Merkel cell carcinoma. The cat was presented with a cutaneous mass in the lumbar region which was histopathologically diagnosed as Merkel cell carcinoma with lymph node metastasis. Multifocal cutaneous lesions were also observed in the dorsal region. They were histopathologically diagnosed as Bowenoid in situ carcinoma, basal cell carcinoma, and cutaneous mast cell tumor. The cat died 154 days after initial presentation, and autopsy revealed metastatic lesions of Merkel cell carcinoma in the pelvic cavity. This report describes the detailed autopsy and histopathological findings of a feline Merkel cell carcinoma accompanied by various other cutaneous tumors.

The efficacy of afoxolaner for canine demodicosis was evaluated in six cases (generalized type: five cases, localized type: one case) of Demodex canis infestation. Afoxolaner was administered orally at the doses of 2.7–5.6 mg/kg of body weight on day 0 and at 3 to 6 week intervals. The administration frequency of afoxolaner required for the disappearance of mites was one time in two cases, two times in three cases, and three times in one case. Cutaneous lesions took 4–12 weeks to heal after initial treatment in all cases. No adverse reactions were recorded in the follow-up with owners, or were found in the physical examination at the reexamination visit during treatment with afoxolaner. In addition, no clinical recurrence was observed in any case in the 6 months in all cases after the final medical examination. On the basis of these results, afoxolaner is effective for the treatment of canine demodicosis.