Sheep farming

INFOGRAPHIC: How to control flies around your flock

Flies aren’t just a nuisance, they also carry diseases, bite and irritate your flock for much of the year. But here's the good news; you can stop them from taking a bite out of your farm’s profits.

Take a look at the infographic below to learn why you should tackle flies early and how to do it.

What to look for

The peaks of the graph in the infographic show us that face and horn flies often appear first. By the height of summer, horse and head flies have started to feast on the blood and sweat of your sheep. Blowflies and their maggot stages are a persistent threat throughout the season.

Moving into the autumn, stable flies begin to attack the legs and abdomen of your sheep. All the while, nuisance and other biting flies, including midges, are wreaking havoc too.

To get on top of a fly invasion, you’ll need to know as soon as numbers are on the rise. Otherwise, by the time you notice your flock is under siege, the fly population will have already exploded. Ideally, catch them early on before the numbers can grow.

Fly traps are an ideal way to keep an eye on fly populations. Included in the infographic is an illustrated guide on how to make them. All you need is a plastic bottle, some bait, and a place to hang them.

The frightful effect of flies

Flies contribute to the spread of viruses like Schmallenberg and Bluetongue, which have caused issues on British farms in previous years and are a threat again now.  What you might not realise is that they also contribute to stress in sheep.

As illustrated in the chart below, sheep can lose up to 5.5kg in weight over a matter of days, which can take 36 days to regain.

There are detrimental economic effects not only with weight loss but a loss of wool quality too. This is predominantly because blowfly moves through a short life cycle, including a maggot stage. These legless larvae along with the adult flies can reduce wool production by up to 26%, so it’s no small loss to your wallet.

Sheep don’t have to suffer

 As well as fly traps, you can treat your flock for flies and monitor trends: 

DYSECT® SHEEP POUR-ON SOLUTION                           

Use a pour-on solution like Dysect® to kill and prevent blowfly, but also treat ticks and lice.  


Use Spot OnTM to tackle blowfly maggots, lice, ticks, and keds, right at the point of irritation.

Be Prepared

Follow the spread of flies and other parasites affecting farms on Twitter; @Sheep_farmers and on Facebook; SheepfarmersUK or visit the Parasite Watch website to see what’s happening on other farms in your area on a live, interactive map.

More information about fly treatments can be found in the infographic below.


For further information, please see the product SPC, or contact your veterinary surgeon, SQP or Zoetis UK Ltd, Walton Oaks, Dorking Road, Walton on the Hill, Tadworth, Surrey, KT20 7NS. Customer Support 0845 3008034. . Always seek the advice of your medicines provider. Use medicines responsibly ( AH447/17