Supporting Australia's ability to sell livestock and livestock products
Australia’s ability to sell livestock and livestock products depends on evidence from our surveillance systems that we are free of livestock diseases that are reportable or which affect trade. To gather this proof of freedom, the Department of Agriculture and Food, Western Australia (DAFWA) investigates cases where livestock show signs of disease similar to reportable or trade diseases.
The WA livestock disease outlook – for producers (WALDO) is collated from information collected by DAFWA and private veterinarians as part of proving Australia’s freedom from those diseases and in 2015/16 allowed WA to access export markets valued at $2 billion.
Recent significant cases submitted to DAFWA Diagnostic Laboratory Services (DDLS)
Case data from November 2016 to January 2017
Sudden death of 12 ewes in the Great Southern
- Twelve ewes were found dead in a mob of 600 on a farm in the Great Southern. The ewes were in good condition and grazing predominantly ryegrass pasture.
- When the mob was moved, two ewes began convulsing and died.
- A postmortem on two ewes found congested lungs and rumens containing dry pasture and an unidentified green plant with oval, opposing leaves.
- The rumen contents tested negative for annual ryegrass toxicity (ARGT) but positive for fluoroacetate.
- As convulsing can be an indicator of transmissible spongiform encephalopathies (TSE) such as scrapie, the laboratory carried out exclusion testing and the results were negative.
Exclusion testing is vital to prove Western Australia’s freedom from significant diseases such as TSE. Producers and veterinarians can obtain subsidised testing under various programs for veterinarians to investigate animal diseases.
Foot-and-mouth disease and bluetongue virus exclusion testing in a heifer in the South-West
- An eight-month-old, white-faced heifer from a property in the South-West was presented to a private vet for investigation of sores on the nose and mouth, drooling and lethargy. Photosensitisation was suspected.
- The heifer had increased lung sounds, fever, reduced rumen sounds and an area of blistering skin near the mouth that looked like sunburn. The under-surface of the tongue was red, the heifer was drooling and had profuse nasal discharge.
- Whenever animals show signs of ill-health like this, it is vital to call a vet to rule out exotic diseases that could affect our markets or public health such as foot-and-mouth disease (FMD), vesicular stomatitis, bluetongue virus and bovine herpes virus type 1.
- Exclusion testing for FMD, vesicular stomatitis, bluetongue virus and bovine herpes virus type 1 produced negative results.
- Routine blood tests showed mildly elevated liver enzymes, which could support a diagnosis of photosensitisation along with the clinical signs.
Producers can help protect Australia from FMD by being vigilant for disease signs in their animals. The most likely way FMD virus would enter Australia would be through the illegal importation of meat and dairy products or from overseas travellers entering with clothing, footwear or equipment that have been contaminated with the virus.
Learn more about how early recognition and reporting can reduce the impacts of FMD.
Hendra virus exclusion on a property in the Pilbara
- A 20-year-old mare on a Pilbara property showed neurological signs, elevated heart rate, muscle tremors, weight-shifting on her feet and violent response to stimuli that led to seizures. The mare was euthanased.
- Five days later, a six-year-old gelding from the same paddock showed similar signs of illness. As the horse had neurological signs and there were flying foxes in the area, the vet took samples to test for Hendra virus from the gelding and horses in neighbouring paddocks including bloods, nasal swabs, water, feed and hay. Testing for Hendra virus was negative.
- A point source poisoning such as organophosphate or strychnine poisoning was thought to be the cause.
- In the following two days, the gelding deteriorated with frequent periods of collapse. He was euthanased and a postmortem was performed. The brain was included with the sample set.
- Strychnine, fluoroacetate and organophosphate were not detected on a general toxin screen.
- Testing at DDLS and Australian Animal Health Laboratory (AAHL) confirmed that all horses were negative for Hendra virus.
- Further exclusion tests for the reportable diseases equine encephalomyelitis (eastern, western, Venezuelan) and West Nile virus were negative. Murray Valley encephalitis was also excluded.
- Faecal testing of the gelding returned a positive result for ARGT. Hay samples (brought-in from the South-West) returned as high risk for ARGT while chaff samples were negative. Subsequent testing of hay from suspect bales returned a positive result for ARGT in eight out of 11 samples.
- Producers are recommended to request a vendor declaration for brought-in hay, grain and chaff to ensure the feed they buy does not harm their animals.
If you suspect your horse may be showing signs of Hendra virus and it has had contact with flying foxes or horses from Queensland or New South Wales, contact your veterinarian or the Emergency Animal Disease hotline on 1800 675 888 for advice before handling or close contact.
Read more about managing the risk of Hendra virus in WA.