Australian Veterinary Journal最新文献

The causative agent of canine heartworm disease, Dirofilaria immitis, requires specific temperature conditions to mature within its mosquito vector, and therefore (re-)infect a canid host. Suitable temperature conditions are not continuously met for locations where most (>97%) Australians and their pet dogs live. The length of the disruption in the transmissibility of D. immitis varies greatly across Australia, and to some degree, between years. We developed an online dashboard 'Transmission Tracker - Dirofilaria' that processes near real-time temperature records across Australia and allows users to enquire about historical and current weather suitability for canine heartworm transmission at any Australian postcode of their interest. This information allows veterinarians to access when, and for how long, heartworm may be transmitted at a specific location, assess the associated risk of infection and advise on a patient-dependent dirofilariosis prevention plan for their canine patients and guardians. Our dashboard is publicly accessible at: https://heartworm-mapping.adelaide.edu.au/shiny/.

Nocardia infections in cats most commonly present as subcutaneous wounds, or less commonly, as pneumonia, purulent pleurisy and disseminated disease. Abdominal involvement is rarely reported, and to date, localised retroperitoneal infection has only been reported in people. This report describes a five-year-old domestic shorthair cat living in Canberra, Australia, that presented with a two-month history of pyrexia and inappetence progressing to anorexia. Ultrasonography showed a large retroperitoneal mass incorporating both ureters. Euthanasia was elected because of the guarded prognosis. Necropsy examination revealed the mass to be comprised of extensive pyogranulomatous inflammation with fibrosis, Splendore-Hoeppli phenomenon and filamentous Gram-positive bacteria. Culture and MALDI-TOF mass spectrometry identified the causative agent as Nocardia brasiliensis. N. brasiliensis is commonly diagnosed as a cause of cutaneous nocardiosis in Australian human patients, but to date has only been reported in one cat from the United States and one dog from Australia. A treatment approach that might have been used in such a case is provided even though the cat's owners elected not to proceed with surgical intervention.

Variations in canine breeds presenting with steroid responsive meningitis-arteritis (SRMA) have been observed across different geographical regions internationally. However, there are no published studies describing affected dogs in an Australian population to date. This descriptive study aimed to characterise the signalment, as well as the clinical characteristics and outcomes in an Australian population of client-owned dogs with SRMA. Medical records from five veterinary referral hospitals in the state of New South Wales between 2013 and 2023 were retrospectively reviewed. One hundred and twenty four dogs were included in the study. The breeds which presented with SRMA most commonly included Golden Retriever (19/124, 15.3%), Italian Greyhound (11/124, 8.8%), Boxer (8/124, 6.5%), "Cavoodle" (Cavalier King Charles Spaniel x Poodle) (8/124, 6.5%), Corgi (7/124, 5.6%), Border Collie (6/124, 4.8%) and Australian Kelpie (5/124, 4.0%). The disease was observed more commonly in males, representing 79/124 (63.7%) of dogs. Presenting concerns, examination findings and laboratory abnormalities were otherwise consistent with international studies. The frequency of ≥1 relapse for dogs with a ≥6-month follow-up period was 32/85 (37.6%). A higher frequency of ≥1 relapse was seen in female dogs and in Corgi and Italian Greyhound breeds. All Corgis who relapsed demonstrated multiple relapses. In conclusion, this study observed a variation in breeds presenting with SRMA compared to international publications, which may reflect both differences in breed popularity, as well as varying interbreed susceptibility dependent on geographical location.

Foot and mouth disease (FMD) remains endemic in many areas of continental Southeast Asia (SEA). It is responsible for substantial economic losses in the smallholder sector and threatens livelihoods. In recent years, novel diagnostic tests have been developed which reportedly detect FMD virus more effectively and efficiently. This critically appraised topic (CAT) aimed to evaluate the feasibility of these diagnostic tests for FMD in SEA compared to conventional tests. Relevant studies that evaluate diagnostic tests are identified and critically assessed, and recommendations are made on suitable potential diagnostic tests for use in the smallholder sector in SEA. A systematic search of electronic databases (CABI: CAB Abstracts, Web of Science Core Collections) was carried out to identify relevant studies that compared novel and conventional diagnostic tests. The search strategy initially identified 12 papers, of which six fulfilled all the inclusion criteria and were selected for this review. Most of the selected studies had limitations in design and comparability, making it difficult to validly compare the effectiveness and efficiency of the relevant diagnostic tests. These limitations include variation in sample characteristics, methodology, measurable outcomes and the different aspects of the diagnostic tests that each study focused on. Most studies concluded that novel diagnostic tests were more effective and efficient than conventional tests: had greater analytical sensitivity and specificity, were more robust, had a wider range of processable sample types and serotypes, could detect various diseases, had faster testing speeds and provided greater value for money. However, strong recommendations on which specific diagnostic test to rely on could not be made, since there was conflicting evidence and multiple confounding factors. Overall, the evidence found did not entirely apply to the target scenario, being SEA smallholder farms. Recommendations for the target scenario were also made based on the study findings.

Background: The level and cause of ewe mortality over the peri-parturient period is poorly understood in Australia. The purpose of this study was to determine the frequency of peri-parturient ewe mortality and investigate the causes of death in commercial, non-Merino ewes over the peri-parturient period.

Methods: An observational study involving 50 commercial, non-Merino farms across southern Australia during two lambing seasons was conducted. The study population was the breeding flock of ewes on each farm. Ewes were monitored by farmers from the time they were first placed in their lambing paddocks before lambing, up until lamb marking (the lambing period). The project required no change to normal practice. Veterinarians conducted postmortem (PM) examinations at three time points on each farm over the lambing period. A standard PM protocol was followed by all participating veterinarians.

Results: The mean peri-parturient mortality over the lambing period was 2.5% in Year 1 and 2.0% in Year 2, with no significant difference between years. Factors that increased the risk of peri-parturient ewe mortality included ewe age (>5 years old) and litter size (triplet-bearing ewes). The most common causes of ewe death according to farmers was dystocia and unknown causes. The three most common diagnoses on veterinary PM examination were dystocia, septicaemia and trauma.

Conclusions: This study reveals the relative importance of each cause of ewe mortality over the peri-parturient period. Risk reduction could include identification and management of older ewes (aged above 5 years or older) and ewes carrying twins or triplets.

A 2-year-old cat was referred for suspected generalised seizure activity and reclusive behaviour, with a history of non-resolving facial abscess. Magnetic resonance imaging (MRI) revealed a contrast enhancing lesion occupying the left calvarium and adjacent peripheral tissues. The intracranial lesion was causing significant mass effect, with oedema and transtentorial herniation. Nocardia nova was isolated from the lesion and identified by DNA sequencing. Treatment consisted of debridement via craniotomy and ventral bulla osteotomy, and combination antibiotic therapy with clarithromycin, amoxycillin and trimethoprim-sulfonamide (sulfadoxine parenterally, then sulfadiazine orally). After several weeks of antibiotic therapy, the cat developed weakness, bicavitary effusion, myxoedema, non-regenerative anaemia and azotaemia. Total thyroxine (TT4) was below the detectable limit and canine thyroid stimulating hormone (cTSH) assay was markedly elevated at 7.53 ng/mL (reference interval 0.15-0.3 ng/mL). Discontinuation of sulfonamides and administration of levothyroxine resulted in resolution of clinical signs. The cat was subsequently able to discontinue levothyroxine, with recovery of euthyroid state. To the authors' knowledge, this is the first report of clinical hypothyroidism in a cat treated with sulfonamide antibiotics and may influence antimicrobial selection and monitoring during therapy. This report also described the management of an atypical presentation of nocardiosis with intracranial extension.

Detecting pathogens in endangered animal populations is vital for understanding and mitigating threats to their survival. The critically endangered western ground parrot (Pezoporus flaviventris, WGP), with a population as low as 150 individuals in Australia, faces an imminent risk of extinction. Despite this urgency, research on viral pathogens in this species remains limited. This study aimed to identify and characterise viruses present in faecal samples from seven individual WGP using a viral metagenomic approach. Analysis of the sequenced datasets revealed the presence of a novel virus belonging to the Parvoviridae family, named psittaciform chaphamaparvovirus 7 (PsChPV-7). The genome of PsChPV-7 contains typical structural and functional gene sequences found in Parvoviridae but is highly divergent, indicating its classification as a distinct species. Phylogenetic analysis placed PsChPV-7 within a unique sub-clade of the Chaphamaparvovirus genus, suggesting its evolutionary significance as an ancient lineage within this group. These findings may contribute to the development of strategic management and biosecurity plans aimed at conserving this endangered WGP.

Identification of risk factors for race day injury can improve greyhound welfare. Race day fractures are the most significant injury event and have the greatest negative impact on dog welfare and the industry's social license to operate. This study aimed to describe the incidence and risk factors for race-related fractures in greyhounds racing in Western Australia. Electronic extracts describing race level data and race day injuries were provided by Racing and Wagering Western Australia (RWWA). The incidence rate (IR) of fractures for all greyhound race starts in Western Australia from 1 January 2017–31/12/2023 was calculated per 1000 starts. Univariable and multivariable models using Poisson regression were used to calculate the IR ratio of fracture type based on race and greyhound-level factors. There were 198,008 racing starts and 662 (n = 643, 97.1% involving the limbs) fractures resulting in an IR of 3.3 fractures per 1000 starts (95%CI 3.1–3.6). Greyhounds that had an injury in their previous race were 2.3 times (95%CI1.4–4.3) more likely to have a forelimb fracture than greyhounds that did not have an injury (P = 0.013). The risk of tarsal bone fracture was greater in greyhounds older than 30 months and greyhounds that had not raced in the previous 15 days. Risk factors for fractures in the forelimb were associated with trauma after interference or dog collisions, whereas tarsal fractures were associated with strain and cyclic loading from race training/racing. Changes to racing structure, rules and policies based on these risk factors may help to reduce fracture incidence in racing greyhounds.

Efficient traceability is paramount for Australia's biosecurity system and market access. Electronic identification (eID) offers higher traceability performance than that achieved with visual and mob-based identification used for the sheep and goats National Livestock Identification System (NLIS). The current study aims to gain an understanding of the barriers and motivations of using eID for NLIS sheep and goats in New South Wales (NSW) and to provide recommendations to support the transition to eID. A social research study using a mixed-methods approach was used through semi-structured interviews and a cross-sectional epidemiological and behavioural study among sheep and goat producers. The COM-B behaviour change model based on capabilities, opportunities and motivations was used as a framework for the study. A total of 269 participants informed this study: 25 interviews were conducted with government, industry and private stakeholders, and 184 and 58 sheep and goat producers participated in the cross-sectional study, respectively. The study identified poor understanding of the purpose and importance of NLIS among producers, with over two-thirds not supporting eID implementation. The main barriers identified to the eID implementation were practical, including costs, technology quality and increased workload. Attitudinal, behavioural and knowledge barriers, such as the perception of the current system providing efficient traceability and the perceived lack of benefits of eID were also identified. This study provides an in-depth analysis of practices and perceptions of stakeholders and producers on sheep and goat traceability and recommendations to address barriers identified, based on education and appropriate behavioural and technical support.

The clinical findings associated with a bleeding disorder, suspected to be an immune mediated pathogenesis comparable to bovine neonatal pancytopenia (BNP), in a 14-day-old Holstein calf are summarised. The clinical examination, clinical laboratory findings, treatment, postmortem findings and referral laboratory diagnostics are reported and discussed in relation to existing knowledge of bleeding disorders in cattle. Veterinary attention was required for a twin 14-day-old Holstein calf that was lethargic, weak and had pale mucous membranes. On clinical examination the calf was tachycardic had pale mucous membranes with petechial and ecchymotic haemorrhages on the ventral surface of the tongue, petechial haemorrhages on the vulval membranes and scleral haemorrhage. The calf received 1.1 L of whole blood from a donor cow to which the calf initially responded. The calf's health appeared to wax and wane over the following 19 days and despite further intervention, the calf died. A postmortem was carried out and samples were submitted to the state laboratory for cytological, histopathological, parasitological and serological examination. Although no exact aetiology was found, there is evidence to suggest that the bleeding disorder was immune-mediated, with a pathogenesis comparable to BNP. To the author's knowledge, this case report is the first peer-reviewed manuscript to describe the clinical presentation similar to BNP in an Australian Holstein calf.