Fly control

By Jill Kelly, District Vet, Central West Local Land Services

October 2019

Are the flies driving you crazy? They also are probably annoying your stock! Studies have shown that nuisance flies can reduce production and weight gains of animals if present in really high numbers, as well as spread diseases such as pink eye in cattle, and marking or mulesing infections in sheep.

Many producers have been asking about fly repellent products for livestock. There are many types on the market. My advice is to choose one that is registered for use against the domestic house fly (Musca domestica) and that is specifically targeted against external parasites.  Using dual purpose chemicals that treat internal worms, as well as external parasites and flies can add to drench resistance problems on farm, so is not advisable, unless your animals really need a drench too!

Always apply fly prevention chemicals carefully, at the recommended dose rates, and with a proper applicator.  Don’t be tempted to splash the cattle products on the dogs or the sheep – these products can be toxic in species that they’re not designed to treat.

It’s also a good idea to think about other ways that you can manage flies, aside from chemicals. Fly traps are a good idea, especially around stock yards or intensive feeding areas. Cleaning up manure can also help to reduce numbers.

In terms of pink eye control, there is a vaccine on the market for cattle, which might be worth considering this year considering the hot, dry, dusty forecast and the current fly burden.  I am also advising people to delay marking stock until the flies abate. Hopefully this occurs soon!

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