Reptarenaviruses in apparently healthy snakes in an Australian zoological collection.

BACKGROUND: Inclusion body disease (IBD) is a disease of snakes with a global distribution and has recently been shown to be caused by reptarenaviruses. Testing for this group of viruses in asymptomatic snakes allows the association between infection and disease to be further elucidated. METHODS: A reptarenavirus was detected by RT-PCR in a reticulated python (Malayopython reticulatus) from an Australian zoological collection that was open-mouth breathing and had erythematous oral mucosa. Another 27 pythons, 4 elapids, 2 colubrids and 2 boas from this collection were then screened. From these animals, swabs, whole blood and/or tissue were tested for reptarenaviruses by RT-PCR. Additionally, blood films from 10 snakes were examined by light microscopy for the presence of inclusion bodies. The majority of samples were collected over a 484-day period. RESULTS: A total of 8 animals were RT-PCR-positive (8/36 = 22.2%): 6 were pythons, 1 was a corn snake (Pantherophis guttatus) and 1 was a Madagascar tree boa (Sanzinia madagascariensis). From them, 57 samples were collected, but only one from each animal was RT-PCR-positive (8/57 = 14.0%). From all 36 animals in this study, 8/182 samples were RT-PCR-positive (4.4%). Inclusion bodies were not recognised in any of the blood films. Only the reticulated python showed signs of illness, which improved without any further intervention. All other RT-PCR-positive snakes were apparently healthy throughout the duration of the study. CONCLUSION: This study showed a weak association between the presence of reptarenaviruses and disease. Testing serially collected swab and whole-blood samples increased the number of animals in which reptarenaviruses were detected.

Cryptococcosis in Gilbert's and long-nosed potoroo.

Two cases of fatal cryptococcosis are described, one of Cryptococcus neoformans infection in a Gilbert's potoroo (Potorous gilbertii) and one of Cryptococcus gattii infection in a long-nosed potoroo (Potorous tridactylus). The diagnoses were confirmed by culture and specific immunohistochemistry, respectively. The long-nosed potoroo tested positive using the latex cryptococcal antigen test (LCAT), whereas the Gilbert's potoroo had a negative LCAT result despite having advanced disease of some duration. In both cases, the clinical presentation was a progressive neurologic disease associated with a central nervous system infection. Pulmonary infection was also observed in the long-nosed potoroo. Specific treatment with antifungal agents was unsuccessful in the long-nosed potoroo.

Evaluation of pulmonary volumetric morphometry at the light and electron microscopy level in several species of passerine birds.

The lungs of 3 small passerine species, having similar body mass but different diurnal activity patterns, were analysed morphometrically to assess the relationship between diurnal activity and pulmonary volumetry at the light and electron microscope levels. The percentage volumes of the major lung and exchange tissue components of the 3 species--an aerial insectivore, a foliage gleaner/nectarivore and a ground forager--were strikingly similar, and consistent with literature values for other passerine species. The only significant difference found was exchange tissue plasma volume and pulmonary haematocrit, with the ground-foraging, low activity Malurus splendens having significantly lower values than the other 2 species. This may indicate that cardiovascular parameters are more important determinants of metabolic activity in small passerines than aspects of pulmonary anatomy.