Disease control

How can I protect my livestock from being bitten by midges?

There is no way of protecting all livestock from being bitten by midges. Use wind to your advantage as midges cannot fly in high winds.

Some significant factors that affect the spread of BTV are:

  • The time of year, i.e. whether during the active vector season (normally March-September)
  • Meteorological conditions, i.e. temperature and wind direction
  • Proximity and density of neighbouring farms

It is however possible to move infected animals at any time of year.

Control of midges is difficult and although there are things that can be done to reduce their spread, it is unlikely that the risk of them can be removed on any individual farm. Reducing the risk is therefore the aim.

The main preventative measure is movement controls and restrictions for susceptible livestock species in relevant areas to reduce the opportunity for vector transmission between holdings. Midges often accompany the animals as they move e.g. in livestock trailers, therefore moving animals increases the risk of midge spread too.

Unless specifically directed to by an inspector, or instructed to by the conditions of an official notice, declaration or licence, you are not required to take action to kill or control insects around your premises. However, you may wish to consult your veterinary surgeon for advice on any protective steps you might take.

There is no evidence that insecticides (applied to the animal) can kill midges fast enough to prevent the first bite and will not prevent onward transmission of bluetongue. There are no products licensed for Culicoides ‘control’. Residual spraying of insecticides around your farm would present a significant environmental risk to all other insects.

There is no evidence that insect repellents prevent onward transmission of bluetongue virus. Repellents have very short retention/efficacy times, especially in the rain. Any products claiming medicinal effects are doing so illegally.

Whilst insecticides do kill insects, their efficacy on Culicoides midges has not been shown outside of the laboratory, and there is no evidence that use of insecticides on animals reduces bluetongue virus transmission in the field.

Whilst treating with insecticides may feel like ‘doing something’, there is no evidence that they will protect livestock from bluetongue and excessive use will cause considerable negative environmental and ecological impacts. Furthermore, these products have a poor retention/efficacy time (especially in the rain) so would require repeat administration.

There are no products licensed for Culicoides ‘control’. Any products sold for this purpose would be off licence and therefore can only be prescribed by vets.

Midges breed in damp soils with high organic content, such as muckheaps. So, keeping these distant from susceptible livestock and livestock-housing may reduce biting frequency and therefore BTV transmission.

Midge traps are used in midge monitoring, but they are not effective at reducing midge population size.

No. There is no evidence that dipping sheep will kill Culicoides or prevent onward transmission of bluetongue.

Unless specifically directed to by an inspector, or instructed to by the conditions of an official notice, declaration or licence, you are not required to house ruminant animals at your premises. However, you may wish to consult your veterinary surgeon for advice on any protective steps you might take.

Midge nets on buildings were used in The Netherlands, however, it was thought that air movement above the animals (at a speed of >3m/s) was more important in preventing the midges coming into contact with livestock than the nets themselves. ‘Midge nets’ available to purchase often do not have small enough aperture for Culicoides midges (less than 0.5mm aperture) and are very costly.

Effectively screening a whole barn could be practically challenging. Housing animals during a hot summer could have welfare implications if air flow is insufficient

No. Midges tend to bite around the face, ears, legs etc. which will still be accessible.

No. Midges breed in a wide range of habitats. If you remove or cover dung heaps, they will find alternative.

Midges do not like wind or rain. Take advantage of windy, high, colder grazing areas.

How far a midge can fly depends on multiple factors including wind speed, direction and obstacles. Midges will travel up to 3km across land. Midges can be transported further in winds across seas.

There is no way of knowing if midges are infected with bluetongue virus. Midges in the area are more likely to be infected with bluetongue if there are reports of the virus on neighbouring farms.