Rhabdomyosarcoma in a ferret (Mustela putorius furo)

A 5-year-old spayed male ferret showed a subcutaneous mass in the right lateral thoracic wall. Microscopic examination revealed that the neoplasm had proliferated in the subcutis with infiltration into the surrounding tissues. A packed bundle of large polymorphic neoplastic cells, containing abundant eosinophilic cytoplasm and a round to ovoid, occasionally bizarre nucleus, were arranged interwoven. The neoplasm had metastasized to the right axillary lymph node. The neoplastic cells were intensively positive for vimentin, desmin and myoglobin. Skeletal muscle type creatine phosphokinase-positive granules were detected in the cytoplasm. Ultrastructurally, various amounts of disorganized myofibrils with focal density resembling the Z-band were shown in the cytoplasm of the neoplastic cells. The neoplasia was diagnosed as rhabdomyosarcoma.     

Distichiasis in a ferret (Mustela putorius furo)

A 4‐year‐old intact male ferret was presented to the Ophthalmology Service of the Department of Clinical Sciences of Companion Animals of Utrecht University with chronic blepharospasm, epiphora, and conjunctivitis of the right eye. Examination of the eye revealed mild conjunctivitis and three hairs protruding from the openings of meibomian glands in the upper eyelid, providing the clinical diagnosis of distichiasis. The distichia were removed by transconjunctival unipolar electrocautery. Recovery was uneventful, but the original signs recurred 10 weeks after surgery. Ophthalmic examination revealed another distichia at a different location in the same eyelid and it was removed by full‐thickness wedge excision. Histopathological examination failed to reveal the exact origin of the distichia. To our knowledge, this is the first reported case of distichiasis in a ferret.     

Cutaneous melanoma in a ferret (Mustela putorius furo)

A 4-year-old spayed female ferret (Mustela putorius furo) was clinically evaluated for a slightly raised subcutaneous mass in the dorsal lumbar area. The mass was surgically excised and submitted for histopathologic evaluation. Histologically, the mass was composed of closely packeted large, atypical, polygonal to spindle-shaped cells arranged in sheets and short bundles. A few cells contained variable amounts of granular, brown to black intracytoplasmic pigment. Warthin-Starry and Fontana-Masson silver stains demonstrated variable numbers of fine black intracytoplasmic granules in most cells. The atypical cells stained positively for vimentin and S100 protein and negatively for cytokeratin and Melan A. Ultrastructurally, the neoplastic cells contained intracytoplasmic melanosomes in different stages of development. Compound melanosomes were not identified. To our knowledge, this report documents the first case of a spontaneous cutaneous melanoma in the ferret.     

Two unusual tumours in a ferret (Mustela putorius furo)

This case report describes the clinical history, diagnosis and treatment of a ferret with a tumour of the right adrenal gland and insulinomas of the pancreas. Histopathology of both lesions confirmed the diagnoses. Clinical signs of the adrenal gland tumour were a swollen vulva, overgrooming, sexual activity and pruritus. The clinical signs suggesting insulinomas were collapse of the ferret, disorientation and ptyalism. A low blood glucose level assisted the diagnosis of insulinomas. This is believed to be the first reported case of concurrent insulinomas and adrenal gland tumour in a ferret in the United Kingdom.     

Ventricular septal defect in a ferret (Mustela putorius furo)

A four-year-old, castrated male ferret (Mustela putorius furo) was evaluated because of a one-year history of sporadic cough. On physical examination a grade 5 of 6 holosystolic murmur was audible over the right apex of the heart. Radiographic findings included the presence of air bronchograms in apical lobes accompanied by pulmonary venous congestion. Colour Doppler echocardiography revealed a left-to-right shunting compatible with a ventricular septal defect. Medical therapy was initiated at the time of the diagnosis. The ferret was presented again 2 months after the initial examination for coughing and respiratory distress. Echocardiographic findings included tricuspid regurgitation, relative enlargement of left-atrial diameter and decreased systolic function, with presence of pleural effusion. Thoracocentesis was performed and the therapeutic plan was revised. In the following months the symptoms did not recur. In the authors' opinion this is the first report to describe the clinical findings of isolated ventricular septal defect in the ferret. Congenital heart defects are rare in this species, the present ferret being only the second case described.     

Transient diabetes mellitus in a domestic ferret (Mustela putorius furo)

A 3.5-year-old spayed female ferret, fed a diet high in refined sugar, was referred for lethargy, polyuria, polydipsia, and polyphagia. Diabetic ketoacidosis was diagnosed. Treatment included insulin therapy and a low carbohydrate diet. Diabetes mellitus resolved 54 d later, and insulin therapy was discontinued. There has been no recurrence of the diabetes mellitus.     

Gastric adenocarcinoma with ossification in a ferret (Mustela putorius furo)

A 6-year-old female ferret had a firm mass 2 cm in diameter in the pyloric region of the stomach. Histopathologically, the mass was composed of neoplastic proliferation of well-differentiated epithelial cells, showing tubular or glandular growth patterns. Osseous metaplastic foci were often found in the tumor. Tumor cells showed a positive reaction for immunohistochemistry against bone morphogenetic protein-6, an osteogenic factor. A diagnosis of gastric adenocarcinoma with ossification was made.     

Multiple progressive piloleiomyomas in a ferret (Mustela putorius furo): a case report

A 2.5‐year‐old ovariectomized female ferret developed multiple progressive linear and raised nodules on the skin. The first lesions occurred on the tail, which was then amputated. Over the following 3 years, additional lesions appeared in the vicinity of the scar and then further rostrally on the flanks and thorax. Histological and immunohistochemical investigation led to a diagnosis of multiple piloleiomyomas. The unique characteristics of this ferret disease are described and compared with those of multiple piloleiomyomas in humans and with those of other cutaneous smooth muscle cell tumours reported in the veterinary literature.     

Focal thoracolumbar spinal cord lymphosarcoma in a ferret (Mustela putorius furo)

A 6-year-old, castrated male domestic ferret (Mustela putorius furo) was euthanized following progressive hind limb paresis and atonia of the bladder of 1-year duration. Neurological evaluation localized the lesion to the thoracolumbar spinal region, and magnetic resonance imaging showed a focal intramedullary spinal cord lesion. Histopathology revealed an extensive, unencapsulated, poorly demarcated mass within the thoracolumbar spinal cord, diagnosed as lymphosarcoma.     

Luteinizing hormone-dependent Cushing's syndrome in a pet ferret (Mustela putorius furo)

Hyperadrenocorticism in ferrets is associated with increased circulating concentrations of adrenal androgens, whereas plasma concentrations of cortisol and ACTH are usually not affected. Here, we report on a 5-year-old castrated male pet ferret (Mustela putorius furo) in which the major presenting signs were polyuria and polyphagia. Routine biochemistry values were within their reference ranges. The urinary corticoid:creatinine ratio (UCCR) was increased and the plasma ACTH concentration was suppressed. Abdominal ultrasonography revealed an enlarged right adrenal gland and atrophy of the left adrenal gland. Administration of hCG resulted in an increase of plasma cortisol and androstenedione concentrations. Based on these findings LH/hCG-dependent hypercortisolism and hyperandrogenism were suspected and treatment was started with a depot GnRH-agonist implant containing 9.4mg deslorelin. Within 3 weeks after placement of the implant all clinical signs had disappeared. Three months later the endocrine parameters had normalized, while abdominal ultrasonography revealed that the right adrenal gland had diminished in size and the left adrenal gland was considered of normal size. No recurrences of clinical signs were seen within 2 years after placement of the deslorelin implant. At that time urinary corticoid and plasma hormone concentrations were within their reference ranges, and no further change in the size of the adrenal glands was seen. In conclusion, this is the first confirmed case of LH-dependent hypercortisolism in a ferret that was treated successfully with a depot GnRH-agonist.     

Nonbacterial thrombotic endocarditis in a ferret (Mustela putorius furo).

A 4-yr-old male ferret (Mustela putorius furo) was presented with a 3-day history of pelvic limb ataxia and weakness. A cellulitis associated with a deep bite wound was identified and initially treated with antibiotics and anti-inflammatory medication. Two weeks later, a grade IV/VI cardiac murmur was identified on physical examination. Echocardiographic examination revealed irregular thickening of the aortic valve leaflets, with normal chamber dimensions and normal systolic function. The ferret's physical condition rapidly deteriorated and it was subsequently euthanatized. Myxomatous degeneration of the aortic valve leaflets, with ulceration and vegetative lesions, and multiorgan infarctions were identified during necropsy. A bacterial etiologic agent was not identified from blood culture or histopathology. Lesions present were consistent with nonbacterial thrombotic endocarditis, a novel condition in the ferret.     

Mixed urolith (struvite and calcium oxalate) in a ferret (Mustela putorius furo)

Urolithiasis has been reported in veterinary literature in some species of the Mustelidae family, including ferrets. In this species, the most common form of urolithiasis is that caused by struvite. The current study examined the case of mixed urolith in an 8-month-old female ferret (Mustela putorius furo) with antecedents of strangury and hematuria. A cystotomy was carried out to remove the urolith, which had a rough surface and a homogeneously porous interior and was formed by a mixture of struvite (60%) and calcium oxalate dehydrated (40%).     

Clinical and pathologic features of neuronal ceroid-lipofuscinosis in a ferret (Mustela putorius furo)

Clinical and pathologic features of neuronal ceroid-lipofuscinosis in a 4-month-old ferret are reported. Clinical signs including neurological symptoms appeared at 3 months of age and progressed rapidly. By magnetic resonance imaging, severe cerebral atrophy was recognized. Histopathologically, there was severe neuronal loss and diffuse astrogliosis with macrophage accumulations; lesions were found predominantly in the cerebral cortex. Intracytoplasmic pigments were observed in surviving neurons and macrophages throughout the brain. The pigments were intensely positive for periodic acid-Schiff, Luxol fast blue, and Sudan black B and exhibited a green autofluorescence. Electron microscopic examination revealed the accumulation of electron-dense granular material within lysosomes of neurons and macrophages. Immunohistochemically, a large number of saposin-positive granules accumulated in the neuronal cells, astrocytes, and macrophages of the lesions, but significant immunoreactivity for subunit c of mitochondrial adenosine triphosphate synthase was not observed. Based on these findings, the animal was diagnosed as affected by neuronal ceroid-lipofuscinosis.     

Intratesticular benign peripheral nerve sheath tumour in a ferret (Mustela putorius furo)

A domestic ferret was submitted for sterilisation because of right testis enlargement. Oestradiol and cortisol concentrations were within normal physiological ranges, but testosterone was below and progesterone above normal. Microscopically, the right testis, with the exception of a small part of the epididymis, was replaced with neoplastic tissue. The tumour was composed of streams and bundles of closely packed spindle to ovoid cells forming whorls around collagen and capillaries, and separated by a collagenous matrix. In some areas, cells were loosely arranged and separated by a pale myxomatous matrix. The left testis showed atrophy. The majority of neoplastic cells expressed vimentin and S-100 protein, while expression of collagen IV was moderate and there was no expression of glial fibrillary acid protein. On the basis of macroscopical and histopathological findings, and supported by immunohistochemical reactivity, the diagnosis of benign peripheral nerve sheath tumour was made. This is the first report of benign peripheral nerve sheath tumour in ferret testis.     

Tetralogy of Fallot in a 6-year-old albino ferret (Mustela putorius furo)

Tetralogy of Fallot associated with bidirectional shunting across a large ventricular septal defect, was found in a 6-year-old ferret. The prognosis associated with tetralogy of Fallot is usually poor. This case is interesting given the advanced age of the ferret. The bidirectional shunting, responsible for an acyanotic disease, may explain the unexpected prolonged survival in this ferret.