flies on horse ectoparasite


What they are

Flies can affect animals in a number of ways. They can be an irritant, can transmit infection, including parasitic worms, and at their worst can be fatal.

Flies can be parasitic in both their young and adult stages. Notably in the UK, blow flies, including Lucilia sericata, lay their eggs on the fleece of sheep or hair of other animals. The first stage larvae migrate onto the surface of the animal’s skin, initially feeding off the surface layers, but feeding off deeper tissue and blood as they grow and moult. They cause affected animals considerable suffering and illness.

Other fly species such as Stomoxys calcitrans, the stable fly, are only parasitic when adult. They piece the host animal’s skin and feed off their blood.

The main consequence of parasitism by biting flies is fly worry. Fly worry is the action an animal takes to avoid the flies’ presence and attempts to feed. This includes moving into shade, stamping and tail switching but can also be an attempt to escape, which can lead to injury. Over time fly worry can cause a drop in production as animals spend less time feeding and lose weight.

How to control flies

The best way to control flies is through the use of insecticides. These come in a variety of forms including pour-ons, sprays, powders, injections and drops.

However, to treat the problem effectively it is important to identify the specific species of fly. This is because not all drugs are effective for all flies.

In order to identify the species, you will need to remove a fly or larva from your animal. We recommend you do this under guidance from your vet.

We identify fly species

We can identify the fly species you removed from your animal.

Our test kits include instructions on how take a sample, a guide to help you interpret the results and advice on what to do next.

As soon as we’ve completed the test we’ll get in touch and let you know what the results are.