WA livestock disease outlook - for vets 

Spring 2026

Evidence collected from our animal disease surveillance systems demonstrate freedom from significant livestock diseases and underpin Australia’s international and domestic markets. The WA Livestock Disease Outlook – for vets summarises recent disease investigations and surveillance activities undertaken by DPIRD and private veterinarians that contribute to this evidence base.

Image source: iStock - Southern giant petrel

Recent news

H5 bird flu update

As of 3 September 2026, all 10 detections in Western Australia of H5 bird flu have been in sub-Antarctic migratory seabirds, found along the WA coastline from Esperance to Northampton. All WA detections have been in giant petrels, except for one brown skua. There have been no detections in poultry or mass mortalities in wildlife in WA. Visit the WA dashboard on wa.gov.au/birdflu for the latest information on detections.

While WA has been fortunate to date that H5 bird flu has not established in our wildlife, we know that the pathway exists via migratory birds. As the disease is now established in some other states in their wildlife (including marine and land mammals), it may be only a matter of time before WA is further affected. To see the national dashboard of species and locations currently impacted, visit birdflu.gov.au.

What is government doing

Nationally, the response to H5 bird flu is being coordinated by the Department of Agriculture, Fisheries and Forestry (DAFF). The Department of Primary Industries and Regional Development (DPIRD), as the avian influenza hazard management agency in WA, is continuing to lead H5 bird flu preparations and response activities within WA in collaboration with our partners the departments of Biodiversity, Conservation and Attractions and Health and the WA Local Government Association.

DPIRD is continuing to engage with WA veterinarians on H5 bird flu developments via the Veterinary Practice Board of WA, updates on our WA H5 bird flu website, webinars, and surveys on resourcing needed to support continued acceptance of birds at veterinary practices. We have also set up a register for WA veterinarians to assist with the H5 bird flu response.

What large animal / mixed practice veterinarians can do

Advice for clients

Poultry and pet bird owners

• Poultry and pet bird clients can find comprehensive biosecurity information to assist them to reduce the risk of H5 bird flu and a range of downloadable factsheets on our poultry biosecurity webpage.
• Clients can subscribe to our new poultry biosecurity newsletter for regular updates.

Livestock producers

• National risk assessments show that the risk to Australian livestock industries from H5 bird flu is negligible for beef cattle, sheep and goats, and low for pigs and dairy cattle.
• Despite H5 bird flu being present across the world, there have only been sporadic cases reported in alpacas, pigs and goats, and a single case in a sheep. These have all been associated with grazing with poultry and spillover of the virus from livestock grazing a contaminated environment.
• The United States outbreaks in dairy cattle were primarily caused by H5N1 clade 2.3.4.4b genotype B3.13, a different genotype to the one detected in Australian H5 bird flu cases, and outbreaks have not occurred in dairy cattle elsewhere.
• While currently there is no evidence that H5 bird flu has established in WA, it is advisable to maintain good biosecurity, including running livestock separately from poultry, and minimising contact with wild birds and pests.
• Producers should monitor animals as part of their ongoing animal biosecurity, and report unusual illness or deaths in livestock to their DPIRD veterinarian or the Emergency Animal Disease Hotline (EAD) on 1800 675 888. Early reporting is critical for protecting livestock industries and cases may be eligible for a subsidised Significant Disease Investigation.
• For further information, read the livestock risk assessment factsheet.

Pet owners

• Cats are particularly susceptible to H5 bird flu, and if H5 bird flu establishes in WA wildlife, cat owners should not let their cats roam, as contact with infected carcasses (such as birds) can lead to cat infection. Restricting cat access to wildlife also reduces predator pressure on WA birdlife.
• Dogs are also susceptible to H5 bird flu, but less than cats. Owners are encouraged to keep dogs on lead in wildlife areas, and not to enter wildlife areas where the disease is known to be present.

Be alert for signs and report

In your day-to-day role, WA veterinarians are critical in the early detection of emergency animal diseases and should remain alert for:

• sudden increases in bird mortality
• respiratory disease outbreaks in poultry
• drops in egg production in poultry
• neurological signs in birds
• unusual disease events in wildlife.

Any form of avian influenza, including H5 bird flu, is a reportable disease. Report suspect signs to the EAD Hotline on 1800 675 888.

Resources for veterinarians investigating avian influenza 

National and state guidance documents are available to support the safe investigation and management of suspected avian influenza cases. Updated guidance is available at:

• birdflu.gov.au 
• wa.gov.au/avian_influenza (on the Resources tile)

If you have general H5 bird flu enquiries, please email H5birdflu@dpird.wa.gov.au. 

Recent disease investigations 

Oral lesions in dairy calves investigated in the Great Southern

• Mucosal ulceration was observed in an 18-day-old Friesian calf from a group of approximately 50 dairy calves in the Great Southern region.
• Lesions affected the gums, hard palate, tongue and muzzle. The calf was bright, feeding well and had no foot lesions or pyrexia. Several additional calves subsequently developed similar lesions.
• Given the presence of oral lesions, differential diagnoses included foot-and-mouth disease (FMD), bovine viral diarrhoea virus (BVDV/pestivirus) and bovine papular stomatitis.
• Initial testing of blood and faecal samples was negative for pestivirus, FMD and vesicular stomatitis virus (VSV). Faecal parasitology was unremarkable, and biochemistry changes were consistent with mild antigenic stimulation only.
• Follow-up sampling focused on collecting lesion material, including oral mucosal tissue tags and firm swabs of active lesions, to maximise diagnostic sensitivity for vesicular and parapoxvirus testing. PCR testing at DPIRD and the Australian Centre for Disease Preparedness (ACDP) excluded FMD and VSV.
• For investigating vesicular and erosive diseases, the most useful samples are fresh lesion tissue, such as mucosal tags or sections of affected epithelium, placed in viral transport media (VTM). Where tissue samples cannot be collected, vigorous swabbing of lesion surfaces and ulcer margins should be performed to ensure adequate cellular material is obtained. VTM can be obtained from your local DPIRD field vet or DPIRD's Diagnostic and Laboratory Services (DDLS).
• Pan-parapoxvirus PCR and sequencing identified pseudocowpox virus in lesion material. Pseudocowpox is a parapoxvirus closely related to the virus causing bovine papular stomatitis and can cause oral lesions in calves. Infection is commonly associated with contact with infected teat or udder lesions in cows.
• Pseudocowpox is also zoonotic and may cause localised skin lesions (‘milker's nodules’) in people handling affected animals. Appropriate hygiene and use of gloves when examining lesions are recommended.
• This investigation highlights the importance of reporting and investigating vesicular and oral lesions in livestock. It also demonstrates the value of submitting high-quality lesion material, particularly mucosal tissue tags or well-collected lesion swabs, to enable exclusion of FMD and other trade-sensitive diseases while maximising the likelihood of identifying an alternative diagnosis. The investigation provided evidence of WA's continued freedom from these diseases.

African swine fever (ASF) and classical swine fever (CSF) excluded in grower pigs with porcine dermatitis and nephropathy syndrome (PDNS)-like lesions 

• Ill-thrift, bloating, rectal prolapse and skin lesions were reported in mixed-sex grower pigs across multiple grower sites. Four pigs were submitted for investigation, including one pig with red-purple skin lesions over the hindlimbs and rump and cyanotic ears, raising suspicion of PDNS.
• All pigs tested positive for porcine circovirus type 2 (PCV2), although the severity of disease varied between animals.
• One pig had severe lesions consistent with clinical PCV-associated disease, including marked lymphoid depletion and necrosis, characteristic botryoid inclusion bodies within macrophages, interstitial pneumonia, splenic necrosis and severe kidney lesions.
• Kidney lesions included glomerular necrosis, protein loss, tubular damage and fibrinoid necrosis of renal blood vessels. Together with the reported skin lesions, these findings were highly suggestive of PDNS.
• PCV2 antigen was widely distributed throughout affected tissues, confirming active systemic PCV2 infection.
• Two additional pigs had only mild lymphoid lesions and low levels of PCV2 antigen, consistent with subclinical infection.
• ASF and CSF were considered as differential diagnoses due to the haemorrhagic and systemic lesions observed. Both diseases were excluded by PCR testing, providing ongoing evidence of WA's freedom from these important exotic pig diseases.
• While PDNS has traditionally been linked with PCV2 infection, the exact cause remains unclear. Further testing may help determine whether PCV2 alone, or potentially other circoviruses such as PCV3, contributed to the disease observed in this case.
• This investigation highlights the range of clinical presentations that can occur with PCV infection and demonstrates the value of laboratory investigation in identifying production-limiting diseases affecting pig health and performance.

Seasonal disease surveillance

Diseases to watch out for in spring and samples to collect for laboratory testing.

Note: Always include base samples and any clinical or gross lesions in submissions. For sample submission advice, contact your local DPIRD field vet or the duty pathologist on 08 9368 3351.

To ensure sample quality, fill blood tubes to the indicated line to maintain the correct blood-to-anticoagulant ratio and mix gently, then allow samples to cool to room temperature before chilling. Avoid placing tubes in direct contact with ice bricks during transport to minimise artefactual haemolysis. 

Diagnostic tip: collecting gastrointestinal samples for total worm counts in sheep.

When a total worm count (TWC) is required:

1. Drain the abomasal contents and the first few metres of duodenum into a suitable container, such as a 2 L jar.
2. Mark the original sample volume on the outside of the jar using a permanent marker.
3. Collect routine histopathology samples.
4. Rinse the abomasum and duodenum and gently rub the mucosa to dislodge attached worms.
5. Add the washings to the jar and mark a second level labelled 'washings'
6. Note: The combined gut contents and washings may exceed 2 L, making transport impractical. In these situations, thoroughly mix the sample and submit a representative aliquot of 100-200 mL. Record the original gut contents volume, washings volume, and volume submitted on the submission form.

If prolonged transport is expected:

• add formalin (approximately 5–10% of sample volume)
• clearly label the jar 'FORMALIN ADDED'
• record formalin addition on the submission form.

Image: Internal stomach anatomy of a sheep - 1. Oesophagus, 2. Rumen 3.  Reticulum  4. Omasum 5. Abomasum 6. Spleen.

Historical case spotlight: when an investigation becomes a reportable disease response

In 2024, a private veterinarian was contacted to investigate respiratory disease in a flock of poultry after abnormalities were identified during processing. Clinical signs and the reported level of disease met several criteria for a moderate to high index of suspicion for a reportable disease, including significant morbidity, mortality and epidemiological risk factors. Appropriate samples were collected and submitted to DDLS.  

Laboratory testing subsequently detected low pathogenic avian influenza (LPAI) virus, triggering a coordinated response involving the private veterinarian, producer, DDLS, DPIRD field staff and ACDP.

Response timeline

Day 1

• A private veterinarian investigated the case, collected base samples and submitted them to DDLS for testing.

Day 5

• DDLS detected avian influenza virus in submitted samples.
• Confirmatory testing was initiated through ACDP.
• DPIRD was notified and movement controls were implemented while the investigation proceeded.

Day 6

• DPIRD veterinarians attended the property under enhanced biosecurity procedures.
• Additional samples were collected from affected and in-contact poultry.
• Epidemiological information was gathered, including assessment of potential wildlife exposure and other poultry groups on the property.

Day 8

• Confirmatory testing identified LPAI.
• Concurrent endemic respiratory pathogens were also detected, demonstrating the importance of maintaining reportable diseases in the differential diagnosis list even when endemic disease is suspected.

Following weeks

• Follow-up surveillance and repeat testing were conducted.
• Biosecurity measures were strengthened on-farm.
• Surveillance results provided confidence that infection had not spread to other poultry groups on the property.

Why this matters

This case highlights how a routine submission by a private veterinarian can rapidly transition into a reportable disease investigation. Early sample collection, prompt laboratory testing and rapid communication between the producer, private veterinarian, DDLS, DPIRD and ACDP allowed an appropriate and proportionate response.

Other seasonal resources for producers 

DPIRD provides seasonally relevant information and management resources to support producers across Western Australia, including guidance on pasture conditions, livestock management and climate outlooks. The most recent guide can be found here.

Producers and veterinarians can also subscribe to stay informed through DPIRD’s StockedUp newsletter, which delivers updates on current research, practical production advice, seasonal challenges and upcoming livestock events.

Important disclaimer
The Chief Executive Officer of the Department of Primary Industries and Regional Development and the State of Western Australia accept no liability whatsoever by reason of negligence or otherwise arising from the use or release of this information or any part of it.

Copyright © State of Western Australia (Department of Primary Industries and Regional Development), 2026.