Large felid leucoencephalomyelopathy in a Sumatran tiger (Panthera tigris sumatrae) from an Australian zoo.

CASE REPORT: The clinicopathological features of a case consistent with large felid leucoencephalomyelopathy are described in a 19-year-old, zoo-based Sumatran tiger in which degenerative vertebral disease, renal insufficiency, diaphragmatic hernia and cataracts were comorbid. The principal presenting sign was ataxia, with concurrent deterioration of vertebral stiffness and vision loss. Histological features included marked destruction of the white matter, the formation of large, bizarre astrocytes and accumulation of numerous foamy macrophages (gitter cells). Immunohistochemical investigation of reactive astrocytes revealed several different cytoplasmic proteins. CONCLUSION: This is the first reported case of large felid leucoencephalomyelopathy in Australia.

Axonal Spheroid Accumulation In the Brainstem and Spinal Cord of A Young Angus Cow with Ataxia.

CASE REPORT: An 18-month-old Angus cow presented with rapidly developing ataxia and subsequently died. The finding of large numbers of axonal spheroids in brainstem nuclei and spinal cord grey matter, bilaterally symmetrical in distribution, was consistent with a histopathological diagnosis of neuroaxonal dystrophy (NAD). Most of the axonal swellings were immunopositive to amyloid precursor protein, suggesting that interruption to axonal flow was important in their genesis. CONCLUSIONS: The topographical distribution of axonal spheroids in the brain and spinal cord in this bovine case closely resembled that found in the ovine neurodegenerative disorder termed NAD, in which axonal swellings are the major pathological feature. This appears to be the first reported case of this type of NAD in cattle. The aetiology of the spheroidal aggregations in this case was not determined. There was no evidence from the case history or neuropathology to indicate whether the axonal spheroids in this case involved an acquired or heritable aetiology.

Congenital dyserythropoietic anaemia and dyskeratosis in Australian Poll Hereford calves.

Congenital dyserythropoietic anaemia (CDA) is a heterogeneous group of rare genetic disorders that in humans is characterised by ineffective haematopoiesis with morphological abnormalities in erythroid precursor cells and secondary iron overload. In the 1990s, a syndrome of CDA with dyskeratosis and progressive alopecia was reported in Poll Hereford calves in Canada and the USA. We report the clinical and pathological findings in two Poll Hereford calves with this syndrome from separate properties in South Australia. The animals had a variably severe anaemia, associated with abnormal nucleated red blood cells in peripheral blood, and large numbers of rubricytes and metarubricytes with a characteristic nuclear ultrastructure in the bone marrow. Both calves were born with a wiry hair coat and a progressively 'dirty-faced' appearance associated with hyperkeratosis and dyskeratosis (apoptosis).

Osteosarcoma at the site of titanium orthopaedic implants in a dog.

An Alaskan Malamute underwent unilateral tibial tuberosity advancement (TTA) surgery to stabilise a stifle joint with a deficient cranial cruciate ligament. The dog made an excellent recovery with no postoperative complications, until 20 months post-surgery when he presented with acute onset ipsilateral pelvic limb lameness. Osteosarcoma (OSA) was diagnosed adjacent to the titanium implants. Currently, there is a paucity of information on the epidemiology of OSA adjacent to orthopaedic implants in canine patients. The clinical, radiological and pathological findings of this case of periprosthetic OSA, and a potential causal relationship between titanium implants and bone neoplasia, are discussed.

Canine H3N8 influenza virus infection in dogs and mice.

An H3N8 influenza virus closely related to equine influenza virus was identified in racing greyhound dogs with respiratory disease in 2004 and subsequently identified in shelter and pet dogs. Pathologic findings in dogs spontaneously infected with canine influenza virus were compared with lesions induced in beagle and mongrel dogs following experimental inoculation with influenza A/canine/Florida/43/2004. BALB/c mice were inoculated with canine influenza virus to assess their suitability as an experimental model for viral pathogenesis studies. All dogs inoculated with virus developed necrotizing and hyperplastic tracheitis and bronchitis with involvement of submucosal glands as well as mild bronchiolitis and pneumonia. Viral antigen was identified in bronchial and tracheal epithelial cells of all dogs and in alveolar macrophages of several dogs. Many dogs that were spontaneously infected with virus also developed bacterial pneumonia, and greyhound dogs with fatal spontaneous infection developed severe pulmonary hemorrhage with hemothorax. Virus-inoculated BALB/c mice developed tracheitis, bronchitis, bronchiolitis, and mild pneumonia in association with viral antigen in airway epithelial cells and in type 2 alveolar epithelial cells. Virus was not detected in extrarespiratory sites in any animals. The results indicate that canine influenza virus infection consistently induces acute tracheitis and bronchitis in dogs. Mice may be a useful model for some pathogenesis studies on canine influenza virus infection.

Anal sac gland carcinoma in 64 cats in the United kingdom (1995-2007).

A retrospective study was performed to characterize 64 cases of anal sac gland carcinoma (ASGC) in cats. All ASGCs diagnosed between 1995 and 2007 at a private diagnostic laboratory in the UK were reviewed. Apocrine gland origin was confirmed in a subset of these tumors by immunohistochemistry and the use of the glandular cytokeratin antibody (CAM 5.2). Associated clinical, gross, and histologic features were compared with those of canine ASGC. Anal sac gland carcinoma accounted for 0.5% of all feline skin neoplasms. Thirty-nine of the cats with ASGC were female, with a female male ratio of 1.56. Fifty-two (81.1%) of the 64 tumors were in Domestic Shorthair cats, 5 (7.8%) in Siamese, 3 (4.8%) in Domestic Longhair, 2 (3.1%) in Burmese, and 1 (1.6%) each in a Birman and a Persian cat. Significant differences in prevalence of ASGC among breeds were not detected. Cats ranged in age from 6 to 17 years (median and mean age, 12 years). More than three quarters of the affected cats for which postsurgical outcome was known were euthanatized or died as a direct consequence of the neoplasm, with a median survival of 3 months. Survival rates at 1 and 2 years were 19 and 0%, respectively.