WA Livestock Disease Outlook - for producers

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 2014/15 allowed WA to access markets valued at $1.6 billion.

Recent significant cases submitted to the Animal Health Laboratories (AHL) - mid-February to mid-April 2016

Transmissible spongiform encephalopathies (mad cow disease - TSE) exclusion

  • Sudden death and collapse were seen in a mixed age Angus cattle herd in the Mid-West.
  • Of the 100 in the herd, 13 heavily pregnant animals had died and the remaining 77 were drooling, staggering, aggressive and lying down more than normal with minor body tremors. Two animals had aborted.
  • Two condition score 4-5 animals underwent post-mortem. The animals were heavily pregnant.
  • The post-mortem showed yellow gelatinous fat and pale kidneys and livers. The attending veterinarian made a differential diagnosis of lipidosis, ketosis or pregnancy toxaemia.
  • Due to the nervous signs shown by the animals, DAFWA also tested for TSE, with negative results. TSE testing is subsidised as it supports Australia’s ability to declare freedom from these diseases, which in turn allows us to continue to trade livestock and maintain consumer confidence in livestock product food safety.
  • Laboratory testing of the samples showed fatty build-up in the liver, which is commonly associated with pregnancy toxaemia. Fatty liver due to pregnancy toxaemia was diagnosed.
  • Read more on pregnancy toxaemia and on the Subsidised Disease Investigation Pilot Program.

Brucella abortus exclusion in stillborn calves

  • A Murray Grey herd of 25 animals in the Great Southern had six stillborn calves over two weeks.
  • One stillborn calf was post mortemed, with the only finding a mild pneumonia. The vet took submitted samples for AHL testing.
  • Testing was negative for bovine pestivirus and Leptospira cultures. No other significant bacterial infection was detected.
  • Laboratory testing also excluded Brucella abortus, which supports continuing export markets and public health.
  • Finding the exact cause of abortion cases can prove difficult. To assist in reaching a diagnosis producers are encouraged to contact their vet early in the course of the disease and save any aborted foetuses, placental material and birth fluids for their vet to sample.
  • Several diseases causing abortion in animals are zoonoses. (Able to infect humans). All producers should exercise extra hygiene when handling aborted foetuses or aborted material, including wearing gloves and washing hands and tools in soap/detergent.

African horse sickness (AHS) and Hendra virus exclusion in the South West

  • A six-year-old quarter horse mare had breathing difficulties and swollen tissues of the head, eyelids, cheeks and throat. The next day three other horses on the same property developed similar signs.
  • Blood samples were taken from all horses before giving supportive treatment to reduce tissue swelling. The treatments started to reduce the tissue swelling overnight.
  • Clinical examinations of all horses were inconclusive but due to the clinical signs, the differential diagnosis list included Hendra virus, the exotic disease African horse sickness and fescue toxicosis.
  • Laboratory testing for Hendra virus and African horse sickness were both negative and there was no fescue found in the horse paddocks.
  • A comprehensive history revealed exposure to cut avocado trees over the past four weeks. Avocado toxicosis was diagnosed. The horses were separated from the avocado cuttings.
  • Owners are reminded to be aware of their personal safety and of the possibility of Hendra virus when their horses develop breathing difficulties or unusual health signs. Always seek veterinary advice if you spot something unusual.
  • Read more about Hendra virus.