AUSTRALIAN VETERINARY JOURNAL

'Transmission Tracker - Dirofilaria'- a public dashboard to assess in real-time the temperature-bounded transmissibility of canine heartworm across Australia
Atkinson PJ, Stevenson M, O'Handley R, Nielsen T and Caraguel C
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/.
An evaluation of the efficiency and effectiveness of diagnostic tests for foot and mouth disease: are novel diagnostic tests for FMD more feasible than conventional tests in Southeast Asia?
Tan WY and Ward MP
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.
Peri-parturient ewe mortality in commercial, southern Australian, non-Merino ewe flocks: establishing the frequency and investigating causes
McQuillan MC, Glanville E, Jacobson C, Sherriff L, McGill DM, Whale A and Allworth MB
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.
Zoonotic feline sporotrichosis: a small case cluster in Perth, Western Australia, and a review of previous feline cases from Australia
Miranda L, Gillett S, Ames Y, Krockenberger M and Malik R
Sporotrichosis is caused by species of the fungus Sporothrix that affect human and several animal species. The transmission of sporotrichosis is classically from an environmental source following penetrating injury. The alternative zoonotic route has gained attention due to the rapid and significant spread of cat-transmitted sporotrichosis in South America and Malaysia, resulting in several thousand human and feline cases in recent decades, especially in Brazil. In Australia, sporotrichosis is sporadic and mainly related to environmental sources. Although feline sporotrichosis is rare in Australia, zoonotic transmission occurred in two of five reported cases, including a recent case cluster, which is reported in this article. The investigation of such cases in Australia is important, as cats not only represent a source of infection living in close proximity with humans, but also, they may represent sentinels for the environmental presence of the fungus. To encourage the investigation and reporting of new veterinary cases, we have reviewed Australian sporotrichosis cases in humans and cats and report a new case cluster of feline sporotrichosis in Perth, WA, Australia, with zoonotic transmission. The index case was a kitten who developed severe facial sporotrichosis with prominent involvement of the nasal planum. Two human cases - one suspected and one confirmed - are also described in the owner, who was a veterinary nurse, and the attending veterinarian, respectively, probably from handling the kitten while not wearing gloves. Later, another mature cat in the same household also became infected. The affected cats were successfully treated using combination of itraconazole and terbinafine. To the best of our knowledge, this is only the second case of cat-transmitted sporotrichosis reported from Australia.
Clinical hypothyroidism in a cat associated with sulfonamide administration for the management of intracranial nocardiosis
Halman CF, Gavaghan BJ and Korman RM
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.
Effect of screw placement order on range of proximal tibial fragment rotation adjustment and osteotomy gap formation when using manual reduction during tibial plateau levelling osteotomy (TPLO)
Tay L and Snelling SR
To determine the optimal first proximal screw position which permits proximal tibial fragment rotation adjustment while minimising osteotomy gap formation when a manual reduction technique is used for TPLO in dogs.
Signalment, clinical characteristics and outcomes of an Australian population of dogs with steroid responsive meningitis-arteritis (SRMA) - 124 cases (2013-2023)
Paterson R and Brady S
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.
How do Australian veterinarians perceive professional conduct in their profession?
Huang Q and Van Gelderen I
Professional skills required for meeting standards of veterinary professional conduct demanded by the public, colleagues and the community are recognised as being equally important to the technical skills required of a veterinarian. To reflect current standards in the profession, this project describes how Australian veterinarians perceive aspects of veterinary professional conduct.
Correction to "Cervical intervertebral disc disease in 307 small-breed dogs (2000-2021): Breed-characteristic features and disc-associated vertebral instability"
Effects of age on accuracy of advanced imaging modalities in identifying intervertebral disc extrusions in Dachshunds
Giles A, Gal A and Wilson L
The aim of this study was to ascertain whether patient age was a significant factor for the accurate identification of compressive intervertebral disc extrusions (IVDE) in Dachshunds using non-contrast computed tomography (CT).
Characteristics and outcome of 73 dogs with iron EDTA molluscicide ingestion in Melbourne, Australia (2013-2019)
Lauinger CA, Wright L and Smart L
The objective of this study was to describe the clinical features, treatments and outcomes of dogs with iron ethylenediaminetetraacetate (EDTA) molluscicide ingestion. We aimed to identify potential predictors of serum iron concentration >54 μmol/L; a cut-off recommended for initiating treatment of human iron toxicosis.
A case report of Penicillium chorioretinitis in a Border Collie dog
Wood J, Walsh A, King M and Dutton A
Systemic fungal pathogens typically gain entry through a single portal and disseminate to affect multiple body systems. Infections caused by fungal Penicillium species are rare in dogs, and these cases have a poor prognosis. An unknown Penicillium species was isolated from the right eye of a middle-aged Border Collie without evidence of systemic disease. Due to financial limitations, an extensive diagnostic evaluation could not be performed. Histopathology alone failed to identify the specific causative agent; however, fungal culture on aqueous humor provided the definitive diagnosis. This case highlights the advantage of collecting ocular fluids after enucleation to diagnose atypical fungal infections.
Investigations into disease associations with feline immunodeficiency virus (FIV) infection in lions (Panthera leo) in Australia: a case-control study
Dabydeen A, Herrin KV, Woolfenden L, Hall E, Westman ME and Norris JM
Feline immunodeficiency virus (FIV) is a highly mutable retrovirus with numerous species-specific strains, such as those infecting domestic cats (Felis catus, FIV) and wild populations of nondomestic cats including lions (Panthera leo, FIV). When FIV infection manifests as disease in domestic cats, common presentations include lymphadenopathy, lymphoid malignancies, oral cavity disease, immunological dysfunctions and neurological abnormalities. In contrast to domestic cats, there has been little published evidence of direct FIV disease associations in lions. The objective of the study, therefore, was to conduct a longitudinal case-control comparison of clinical findings and survival analysis of FIV-infected and FIV-uninfected captive lions to investigate possible FIV disease associations in nondomestic felids in Australia.
A review of perioperative mortality in pet rabbits in Australia
Pieper EG, Carter JE, Firestone SM and Baron HR
Domestic rabbits have higher perioperative mortality rates (1.39%-4.8%) compared with dogs and cats (0.1%-0.2%), with cardiovascular and respiratory complications reported most. Understanding anaesthetic risk factors is essential to minimise mortality risks.
Leptospiral infection in domestic mares in North Queensland
Alayil AL, Horwood PF, Gummow B, Picard JA and Joone CJ
Leptospira species are found worldwide, favouring tropical regions, and infect a wide range of animal species. Although renal persistence in infected individuals and excretion in urine is thought to be the primary mechanism of disease transmission, recent reports have suggested that persistence in the reproductive tract may be a feature in certain species, including the horse. The aim of this study was to investigate leptospiral infection, particularly within the reproductive tract, in healthy, non-breeding mares. Serum and endometrial swab samples were collected from 50 mares from the James Cook University Teaching Animal Herd, as well as, where possible, free-catch urine (n = 19). Sera were screened for antibodies to 24 Leptospira serovars, using the microscopic agglutination test (MAT). Endometrial and urine samples underwent real-time PCR testing, targeting the leptospiral rrs gene. Overall, the seroprevalence of leptospirosis was 48% (95% CI: 34%-62%), with serovars Arborea, Bratislava and Australis detected most frequently. PCR positive results were obtained from 1 of 50 (2%) endometrial swabs and 2 of 19 (11%) urine samples. This is the first report of serovar Bratislava in horses in Australia.
Incidence and risk factors for limb fracture in greyhound racing in Western Australia
Gibson MJ, Legg KA, Gee EK, Smet A, Medd J, McMullen C, Auld L and Rogers CW
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.
Bleeding disorder in a Holstein calf comparable to bovine neonatal pancytopenia
Phipps AJ
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.
Evidence of renal tubular injury in canine patients after elective desexing
Male FG and Quinn CT
To investigate the frequency of perioperative acute kidney injury (AKI) in American Society of Anesthesiologists (SA) Grade I canine patients undergoing elective desexing using urine microscopy techniques and assess if pre- and intraoperative factors affect risk of developing AKI.
Surgical excision and omentalisation of mineralised paraprostatic cysts with concurrent ureteroneocystostomy and perineal herniorrhaphy in a 9-year-old male entire Bearded Collie
Moses WB and Tipler AE
This case report describes the diagnosis, management and the short- and long-term outcomes of a dog with paraprostatic cysts and associated perineal herniation. A 9-year-old male entire Bearded Collie was referred for a caudal abdominal mass and right perineal hernia noted on routine examination. Computed Tomography (CT) imaging of the abdomen demonstrated a large bilobed fluid filled structure adjacent to the prostate, extending into the peritoneal cavity and the right perineal space, causing perineal herniation and partial obstruction of the right ureter. Surgical excision of the mass was performed and ureteroneocystostomy was required due to involvement of the right ureter. Excisional biopsy, omentalisation of the prostate and right-sided herniorrhaphy utilising an internal obturator muscle flap was performed. Histopathology confirmed the diagnosis of paraprostatic cyst with extensive osseous metaplasia and multifocal chronic-active interstitial prostatitis. The dog re-presented 16 months later with a left-sided perineal hernia and a left-sided herniorrhaphy was performed. Twenty-nine months after the initial surgery the dog presented with stranguria associated with recurrent bilateral perineal herniation and a retroflexed urinary bladder. Cystopexy and colopexy were performed. No sign of recurrence of the paraprostatic cysts was noted intraoperatively. This is the first reported case of surgical excision of paraprostatic cysts with concurrent ureteroneocystostomy. To the authors knowledge, this is also the longest reported case follow up (>4 years) of a dog following complete excision of paraprostatic cysts.
Lymphoma in two wild tawny frogmouths (Podargus strigoides) in Victoria
Adriaanse KJ, Holz PH, Peacock L, Martin A, Curnick M and Stent A
Lymphoma was diagnosed in two wild tawny frogmouths (Podargus strigoides) presented to the Australian Wildlife Health Centre, Healesville Sanctuary, Victoria. The first case presented with extensive feather loss refractory to treatment. Bacterial and fungal folliculitis and beak and feather disease virus were excluded as primary causes, and the bird was euthanised due to poor response to treatment. Histopathological examination of the skin showed an extensive infiltrate of pleomorphic mononuclear leucocytes, suggestive of cutaneous lymphoma. Immunohistochemistry revealed >95% of these cells were CD3 positive, consistent with T cell lymphoma. The second case presented debilitated and in poor body condition and was euthanised due to poor prognosis. Histopathological examination revealed extensive infiltrates of pleomorphic mononuclear leucocytes in multiple tissues, suggestive of disseminated lymphoma. Immunohistochemistry revealed 70%-80% of these leucocytes were Pax5 positive, consistent with a B cell lymphoma. To the authors' knowledge these cases constitute the first report of malignant neoplasms in members of the Order Caprimulgiformes. Cutaneous lymphoma should be considered as a potential differential diagnosis for severe feather loss in tawny frogmouths and other avian species, when other more common causes have been ruled out. Similarly, disseminated lymphoma is a differential diagnosis worthy of consideration in cases of systemic debilitation in tawny frogmouths.
Retroperitoneal granuloma in a cat caused by Nocardia brasiliensis resulting in bilateral ureteral entrapment and unilateral hydronephrosis
Lee K, Pritchard E, Donahoe SL, Malik R and Krockenberger M
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.