Abattoir Survey of Pneumonia in Sheep Now Complete
Key Points About Pneumonia in Australian Sheep from the Survey
Pneumonia in sheep is common in Australia.
The abattoir survey has revealed widespread infection with Mycoplasma ovipneumoniae in sheep in Australia.
Small numbers of abattoir lots (less than 5%) tested positive for Ovine Parainfluenza-3 Virus or Ovine Respiratory Syncytial Virus.
The abattoir survey of pathogens that cause pneumonia in sheep funded by Animal Health Australia and Meat & Livestock Australia is now complete.
Twenty-four abattoir visits were completed between October 2020 and December 2021, with 1095 samples collected from diseased ovine lungs. The samples represented 253 abattoir lots, including 182 lots of lambs and 71 lots of adult sheep.
Sample collection and polymerase chain reaction (PCR) testing confirmed the findings of my previous research on pneumonia in sheep in Australia, with widespread detection of Mycoplasma ovipneumoniae in lungs from lamb and sheep carcasses sourced from around Australia.
Mycoplasma ovipneumoniae was detected in sampled lots at each abattoir visit (range 28.6% – 100% of sampled abattoir lots).
Across all the abattoir visits, 64.4% of sampled abattoir lots tested positive for Mycoplasma ovipneumoniae.
Abattoir lots positive for Mycoplasma ovipneumoniae came from New South Wales, Queensland, South Australia, Tasmania, Victoria, and Western Australia. No sheep from the Australian Capital Territory were sampled as part of the survey.
Mycoplasma ovipneumoniae
Mycoplasma ovipneumoniae was first isolated from two large sheep flocks in southern Queensland in the 1970s that had shown poor growth rates and reduced exercise tolerance for some years.
Mycoplasmas are a type of bacteria. Infection with Mycoplasma ovipneumoniae predisposes sheep to secondary lung infection with other bacteria such as Mannheimia haemolytica and Pasteurella multocida that normally live in the nose and throat of sheep without causing any harm. Once in the lung these bacteria grow and secrete toxins that cause inflammation and lung tissue destruction.
All breeds of sheep are susceptible to infection with Mycoplasma ovipneumoniae. Infection persists in a flock in chronic carrier ewes and rams, with infection passing from ewes to lambs soon after birth. Ewes shed the bacteria from their nose and throat, as well as in their milk. Lambs may begin showing signs of infection (wheezing, coughing, runny nose, runny eyes, difficulty suckling) from around 1-2 months of birth.
Goats are also susceptible to infection with Mycoplasma ovipneumoniae.
If left untreated, infection with Mycoplasma ovipneumoniae can lead to arthritis in sheep and goats, resulting in swollen, hot, painful leg joints. Animals lose condition quickly and may die.
Ewes and does chronically infected with Mycoplasma ovipneumoniae are more likely to develop mastitis.
When animals have pneumonia, the pleura can become inflamed. Approximately 20% (1 in 5) sheep that have pneumonia from Mycoplasma ovipneumoniae infection will develop pleurisy.
Pleurisy is a problem in processing plants because it makes it difficult to eviscerate the carcass. Read more about this hidden cost of pneumonia in sheep.
Pneumonia in sheep and goats can become a serious matter for any farm. Signs of pneumonia in sheep and goats include coughing, runny nose, runny eyes, mouth breathing, labored breathing, swelling of the leg joints, cloudy eyes, poor growth rates and death. When detected early, treatment can be implemented.
I provide PCR testing for Mycoplasma ovipneumoniae as part of my small ruminant on-farm disease investigations. Please contact me for more information.