Flystrike

Does the idea of maggots feeding on living flesh give you the heebie-jeebies? Us too! 

Fly strike is the term given to having fly eggs laid on living animals which then develop into maggots which live on the animal until they mature. 

It is usually our poor Aussie Merino sheep that is known for developing flystrike, but in reality, any animal can be affected. 

Flies like to lay their eggs on moist, foul-smelling skin or on fresh carcasses. Risk factors for developing fly strike are – constantly moist skin, skin infections, dirty wounds, urine or faecal staining. 

For sheep, fleece rot from constant wetting during rainy periods is a high risk factor, along with diarrhoea from lush feed or worm infections. Long wool is also a risk factor. 

For other companion animals, matted hair around the bottom or vulva/penis can be a risk factor. Rabbits frequently succumb when they are kept in dirty moist hutches and are unable to lift their body away from the moisture (usually old, arthritic rabbits). Any skin infection that is not quickly detected and treated is a prime target. 

Fly strike can be confirmed by visualising maggots crawling across the skin. There is usually a foul odour associated with the strike which becomes familiar to those with sheep – or veterinary professionals! It’s the same rotten smell that attracts the flies in the first place. 

Treatment for all species requires removal of dirty and wet wool/fur and cleansing of the affected skin. Insecticide products may be required depending on the level of infection. Supportive treatments with antibiotics may also be required. There are some residual treatments for flocks of sheep when risk factors are high. 

Prevention is the best course of action. Sheep producers need to be vigilant when checking sheep. Any fouled wool should be removed (crutching, dagging etc). Good parasite control will reduce cases of diarrhoea from worms and supplementing hay when pasture is lush can help to reduce diarrhoea and wool staining. Companion animal owners need to address wet, smelly skin and hair asap