Sarcoptic mange in a wild swamp wallaby (Wallabia bicolor).

A wild adult male swamp wallaby from Victoria was found to be infested with Sarcoptes scabiei. Hyperkeratotic skin lesions were confined predominantly to the head and shoulders. This is the first report of sarcoptic mange in a swamp wallaby.

Increased p16CDKN2A protein within feline cutaneous viral plaques, bowenoid in situ carcinomas, and a subset of invasive squamous cell carcinomas.

Cutaneous viral plaques and bowenoid in situ carcinomas (BISCs) in cats are thought to be caused by papillomavirus (PV) infection. There is evidence that PVs may also cause some feline invasive squamous cell carcinomas (ISCCs). Human oncogenic PVs degrade retinoblastoma (RB) protein, impairing cell cycle control. Loss of RB function also increases p16(CDKN2A) protein (p16), and increased p16 immunoreactivity within a human oral ISCC indicates that the neoplasm was caused by PV infection. In the present study, p16 immunoreactivity was evaluated in 14 feline viral plaques, 14 BISCs, 7 non-solar-induced ISCCs, 11 solar-induced ISCCs, and 14 trichoblastomas. Increased p16 was present within all viral plaques, BISCs, and non-solar-induced ISCCs. In contrast, little p16 immunoreactivity was visible in the solar-induced ISCCs or trichoblastomas. PV DNA was consistently amplified from viral plaques, BISCs, and non-solar-induced ISCCs. However, just 5 solar-induced ISCCs and 1 trichoblastoma contained PV DNA. Given that both increased p16 immunoreactivity and PV DNA were present within viral plaques, BISCs, and non-solar-induced ISCCs, all 3 may be caused by PV infection. This suggests that feline non-solar-induced ISCCs may develop as a result of neoplastic progression from viral plaques and BISCs. Whether PVs promote this progression is unknown; however, evidence from this study suggests the PV that is associated with viral plaques and BISCs is able to disrupt the p16-RB pathway and therefore could have oncogenic potential. Immunohistochemical detection of p16 appears to be a useful technique to investigate the role of PVs in feline skin disease.

Cutaneous sarcoids in captive African lions associated with feline sarcoid-associated papillomavirus infection.

Solitary and multiple cutaneous and mucocutaneous masses were identified in 5 of 24 captive African lions (Panthera leo) over a 6-month-period. All masses were surgically excised, and all were histologically similar to equine and feline sarcoids. DNA was extracted from formalin-fixed, paraffin-embedded tissue. Polymerase chain reaction amplified DNA sequences that had been previously detected in feline sarcoids and clinically normal bovine skin. All lions had been fed a diet that included bovine carcasses that had not been skinned. Since the cessation of feeding bovine carcasses with cutaneous lesions, no additional skin lesions have been observed within any of the lions. Herein is described the clinical, gross, and histopathological findings of sarcoids in 5 captive lions. As the causative papillomavirus most likely has a bovine definitive host, it is hypothesized that the lions were exposed to the virus by feeding on bovine carcasses with skin still attached.

Severity and distribution of ventral thoracolumbar spondylosis and histological assessment of associated intervertebral disc degeneration in cull rams.

AIM: To conduct a pilot study investigating the incidence and pathology of spondylosis in a sample of cull rams in New Zealand. METHODS: Vertebral columns from 51 cull rams from different properties were assessed radiographically for evidence of spondylosis. They were graded according to severity, using a four-point grading system. Samples of intervertebral discs representing different grades of spondylosis were examined histopathologically. RESULTS: Forty (78%) rams had spondylosis in at least one intervertebral space. Of these, 11 had ankylosis involving one or more intervertebral spaces. The frequency of spondylosis was greater in the thoracic than lumbar region (p<0.001), and was most frequent between T10-T11. Histopathological examination of intervertebral discs associated with all grades of spondylosis revealed degenerative changes in the annulus fibrosis. CONCLUSIONS: Spondylosis appeared to be common in cull rams and affected thoracic and lumbar vertebrae. It often involved ankylosis of adjacent vertebrae, and was associated with degeneration of the intervertebral disc. CLINICAL RELEVANCE: Spondylosis may reduce the serving ability of rams and be an important underlying reason for culling. The pathogenesis of spondylosis is unknown but may involve high mating frequencies during the breeding season.

A possible predisposition to dilated cardiomyopathy in Huntaway dogs.

AIM: To compare the prevalence of dilated cardiomyopathy (DCM) in New Zealand Huntaway dogs with the prevalence of DCM in other breeds of dog. METHODS: The necropsy database at Massey University was used to identify cases of DCM diagnosed between January 1999 and March 2006. Dogs were considered to have DCM if echocardiographic, gross necropsy, or histological findings were consistent with this diagnosis. The prevalence in Huntaways was then compared with the prevalence observed in all breeds of dog, as well as the prevalence observed in large breeds of dog. RESULTS: Twelve dogs were identified with DCM. One was diagnosed using echocardiography, while the other 11 were diagnosed by gross necropsy examination. The gross diagnosis of DCM was confirmed histologically in 6/11 dogs. The prevalence of DCM in Huntaways was significantly higher than the prevalence seen in all breeds of dog (p=0.008), and the prevalence in large breeds of dog (p=0.025). All four Huntaways diagnosed with DCM were male, and had an average age of 4 years. Three dogs presented with symptoms attributable to impaired heart function while one presented with symptoms of chronic renal failure. The duration of clinical symptoms prior to presentation ranged between 1 day and 3 weeks. CONCLUSIONS: The results of this study suggest that Huntaways may be predisposed to the development of DCM. Although the increased prevalence in this breed was significant, only small numbers of affected Huntaways were identified, and additional cases are required to confirm these preliminary findings. CLINICAL RELEVANCE: Huntaways are the most common working dog in New Zealand. The premature loss of a working dog is expected to have a significant economic impact on farmers. Further investigation of DCM in Huntaways may allow measures to reduce the prevalence in this breed.