Detection of macropodid alphaherpesvirus 2 infection and lesions in sudden death of a captive Virginia opossum and a water opossum.

Macropodid alphaherpesvirus 2 (MaAHV2) is best described in macropods and has been implicated in outbreaks among captive marsupial populations in Australia. Natural disease caused by herpesviruses has not been reported previously in opossum species, to our knowledge. One Virginia opossum (Didelphis virginiana) and 1 water opossum (Chironectes minimus) were submitted for postmortem examination from a zoo that housed 6 opossums, all of which died within several weeks. Red kangaroos (Macropus rufus) and red-necked wallabies (Macropus rufogriseus) were also present at the facility. Liver samples from both opossums were submitted for transmission electron microscopy and whole-genome sequencing. Microscopically, both opossums had multifocal necrosis in the liver and lung, with intranuclear inclusion bodies within hepatocytes and pneumocytes. Another significant finding in the Virginia opossum was sepsis, with isolation of Streptococcus didelphis from various organs. Ultrastructural analysis of formalin-fixed liver tissue identified herpesviral replication complexes in both opossums; negative-stain electron microscopy of unfixed liver tissue repeatedly yielded a negative result. The herpesvirus had >99% nucleotide identity with MaAHV2. These 2 cases indicate that both opossum species are susceptible to MaAHV2 infection, and the outbreak has implications for mixed-species facilities that house macropods.

Effects of overnight captivity on antioxidant capacity and clinical chemistry of wild southern hairy-nosed wombats (Lasiorhinus latifrons).

An animal's antioxidant capacity is measured by its ability to quench reactive oxygen species (ROS). During everyday metabolism, antioxidants and ROS are in equilibrium with one another. In times of stress, an animal produces more ROS and therefore uses its antioxidant capacity more readily in order to maintain this equilibrium. When the production of ROS exceeds the antioxidant capacity, an animal will experience extensive oxidative stress, which can ultimately affect that animal's health. During experimental study of wild animals, it is often necessary to capture them for a short period of time. In order to obtain a measurement of the effects of short-term captivity on oxidative capacity in wild animals, a population of southern hairy-nosed wombats (Lasiorhinus latifrons) in Swan Reach, South Australia (34.57 degrees S, 139.60 degrees E), was studied. To assess the variation in antioxidant capacity, two assays, the ferric reducing ability of plasma and the trolox equivalent antioxidant capacity, were performed. A third assay, thiobarbituric acid reactive substances, was used to measure the effects of ROS. Measurements of the specific antioxidants uric acid, ascorbic acid, retinol, alpha-tocopherol, and superoxide dismutase were also performed. The biochemical parameters albumin, total protein, cholinesterase, creatinine, and urea were measured as indicators for health. Results showed a significant reduction in antioxidant capacity during the overnight period of captivity.