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Caterpillars & Horses

The University of Queensland is set to help thoroughbred horse breeders combat a hairy caterpillar threat that causes horse abortions and is costing the Australian racing industry millions of dollars every year. 

Bag-shelter moth caterpillars were believed responsible for up to one third of abortions in thoroughbreds, causing equine amnionitis (infection of the uterus) and foetal loss by inflaming the placental membrane. 

The caterpillars are covered with up to 2.5 million dangerous tiny hairs and horses inadvertently ingest them or their nest remains.  The University team has developed guidelines for horse studs and farmers to deal with the threat and are completing a risk assessment of horses’ exposure to caterpillars. 

Bag-shelter moth caterpillars are commonly known as processionary caterpillars because the walk nose-to-tail in lines when they leave their nests on gum or wattle trees.  The recommendation is to remove the egg masses and nests from tree trunks and branches and dispose of them safely.  They can also cause skin irritation and get into the eyes.  Something so innocent can cause so much damage.