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An investigation into the health of green turtles was undertaken near Gladstone, Queensland, in response to a dramatic increase in stranding numbers in the first half of 2011. A total of 56 live turtles were subject to clinical examination and blood sampling for routine blood profiles, and 12 deceased turtles underwent a thorough necropsy examination. This population of green turtles was found to be in poor body condition and a range of infectious and non-infectious conditions were identified in the unhealthy turtles, including hepato-renal insufficiency (up to 81%, 27/33 based on clinical pathology), cachexia (92%, 11/12), parasitism (75%, 9/12), cardiopulmonary anomalies (42%, 5/12), gastroenteritis (25%, 3/12), masses (25%, 3/12) and mechanical impediments (17%, 2/12 based on necropsy). Overall, there was no evidence to indicate a unifying disease as a primary cause of the mass mortality. Recent adverse weather events, historic regional contamination and nearby industrial activities are discussed as potential causative factors.

Purpose. Beak and feather disease virus (BFDV) is a circovirus and the cause of psittacine beak and feather disease (PBFD). This disease is characterized by feather and beak deformities and is a recognized threat to endangered Psittaciformes (parrots and cockatoos). The role that non-psittacine birds may play as reservoirs of infection is unclear. This study aimed to begin addressing this gap in our knowledge of PBFD.Methodology. Liver samples were collected from birds presented to the Australian Wildlife Health Centre at Zoos Victoria's Healesville Sanctuary for veterinary care between December 2014 and December 2015, and tested for BFDV DNA using polymerase chain reaction coupled with sequencing and phylogenetic analyses.Results/Key findings. Overall BFDV was detected in 38.1 % of 210 birds. BFDV was detected at high prevalence (56.2 %) in psittacine birds, in the majority of cases without any observed clinical signs of PBFD. We also found that BFDV was more common in non-psittacine species than previously recognized, with BFDV detected at 20.0 % prevalence in the non-psittacine birds tested, including species with no clear ecological association with psittacines, and without showing any detectable clinical signs of BFDV infection.Conclusion. Further research to determine the infectivity and transmissibility of BFDV in non-psittacine species is indicated. Until such work is undertaken the findings from this study suggest that every bird should be considered a potential carrier of BFDV, regardless of species and clinical presentation. Veterinary clinics and wildlife rehabilitation facilities caring for birds that are susceptible to PBFD should reconsider biosecurity protocols aimed at controlling BFDV.

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Psittacid Adenovirus-2 (PsAdv-2) was identified in captive orange-bellied parrots ( Neophema chrysogastor ) during a multifactorial cluster of mortalities at the Adelaide Zoo, South Australia, and an outbreak of Pseudomonas aeruginosa septicaemia at the Tasmanian Department of Primary Industries, Parks, Water and Environment captive breeding facility, Taroona, Tasmania. This was the first time that an adenovirus had been identified in orange-bellied parrots and is the first report of PsAdv-2 in Australia. To investigate the status of PsAdv-2 in the captive population of orange-bellied parrots, 102 healthy birds from five breeding facilities were examined for the presence of PsAdv-2 DNA in droppings and/or cloacal swabs using a nested polymerase chain reaction assay. Additionally, eight birds released to the wild for the 2016 breeding season were similarly tested when they were recaptured prior to migration to be held in captivity for the winter. PsAdv-2 was identified in all breeding facilities as well as the birds recaptured from the wild. Prevalence of shedding ranged from 29.7 to 76.5%, demonstrating that PsAdv-2 is endemic in the captive population of orange-bellied parrots and that wild parrots may have been exposed to the virus. PsAdv-2 DNA was detected in both cloacal swabs and faeces of the orange-bellied parrots, but testing both samples from the same birds suggested that testing faeces would be more sensitive than cloacal swabs. PsAdv-2 was not found in other psittacine species housed in nearby aviaries at the Adelaide Zoo. The source of the infection in the orange-bellied parrots remains undetermined. In this study, PsAdv-2 prevalence of shedding was higher in adult birds as compared to birds less than one year old. Preliminary data also suggested a correlation between adenovirus shedding prevalence within the breeding collection and chick survival.

Summary Disease is increasingly being recognised as a risk factor in declining wildlife populations around the globe. However, there are limited protocols to assess disease risks in declining wildlife. Using epidemiological principles, we define a step‐by‐step framework to complete this complex and critical task. As an example, we assessed the potential role of diseases in relation to the decline of the woylie or brush‐tailed bettong (Bettongia penicillata ogilbyi) in Western Australia. Between 1999 and 2006, woylie populations declined by 90%. The wildlife disease risk assessment began with a list of all known or suspected diseases to which the woylie, a species of macropod, is susceptible. This list was assessed against the spatial, temporal and demographic characteristics of the decline. Diseases causing widespread and high mortalities or debilitation leading to predation received high scores. Based on this assessment, priority diseases or pathogens for investigation identified were haemoparasites, gastrointestinal helminths, Neospora caninum, Toxoplasmosis (Toxoplasma gondii), Encephalomyocarditis virus, Macropod Orbiviruses (Wallal virus and Warrego virus), Macropod Herpesviruses (Macropodid herpesvirus 1 and 2) and Salmonella spp.

Conservation medicine, as a distinct discipline investigating health and disease in relation to ecosystems, has grown in recent years. Veterinary teams are developing a growing understanding of the key aspects of conservation medicine, including the potential impact of wildlife disease on biodiversity and the importance of wildlife health within the continuum of human and ecosystem health. Perth Zoo veterinary staff have made an increasing contribution to conservation medicine in recent years, encountering both challenges and rewards, and reaching a clearer understanding of how the conservation medicine ethos can be interpreted within a zoo framework. This paper examines ways in which zoo veterinary teams can contribute to multidisciplinary conservation medicine programmes and discusses some of the challenges for further growth of this discipline in zoos. Opportunities for increased conservation medicine activities may exist within the current zoo framework or may be developed through close collaborative links with other conservation agencies. Successful zoo‐based conservation medicine activities rely on strong relationships and broad acceptance across the entire zoo of the importance of conservation medicine outcomes.

Viruses in avian hosts can pose threats to avian health and some have zoonotic potential. Hospitals that provide veterinary care for avian patients may serve as a site of exposure of other birds and human staff in the facility to these viruses. They can also provide a useful location to collect samples from avian patients in order to examine the viruses present in wild birds. This study aimed to investigate viruses of biosecurity and/or zoonotic significance in Australian birds by screening samples collected from 409 birds presented to the Australian Wildlife Health Centre at Zoos Victoria’s Healesville Sanctuary for veterinary care between December 2014 and December 2015. Samples were tested for avian influenza viruses, herpesviruses, paramyxoviruses and coronaviruses, using genus- or family-wide polymerase chain reaction methods coupled with sequencing and phylogenetic analyses for detection and identification of both known and novel viruses. A very low prevalence of viruses was detected. Columbid alphaherpesvirus 1 was detected from a powerful owl (Ninox strenua) with inclusion body hepatitis, and an avian paramyxovirus most similar to Avian avulavirus 5 was detected from a musk lorikeet (Glossopsitta concinna). Two distinct novel avian alphaherpesviruses were detected in samples from a sulphur-crested cockatoo (Cacatua galerita) and a tawny frogmouth (Podargus strigoides). Avian influenza viruses and avian coronaviruses were not detected. The clinical significance of the newly detected viruses remains undetermined. Further studies are needed to assess the host specificity, epidemiology, pathogenicity and host-pathogen relationships of these novel viruses. Further genome characterization is also indicated, and would be required before these viruses can be formally classified taxonomically. The detection of these viruses contributes to our knowledge on avian virodiversity. The low level of avian virus detection, and the absence of any viruses with zoonotic potential, suggests low risk to biosecurity and human health.