If your barn is anything like many that Enviro Equine & PET equine nutritionist Dr. Clair Thunes, Ph.D., visits, you are in the thick of fly season. Horses are plagued by a number of external parasites including house flies, horse flies, stable flies, mosquitoes and culicoides, to name just a few. Annoying to nearly all horses, for some they result in misery. More sensitive horses may develop large welts from biting flies or a condition known as “sweet itch,” which is an allergic hypersensitivity to culicoides biting midges. Horses with sweet itch rub their manes and tails often to the point of becoming raw.

Beyond the discomfort these insects cause, they are also disease vectors that help to transmit sometimes fatal diseases such as West Nile and the Encephalomyelitis conditions. They also help transmit pigeon fever and can lead to the development of summer sores as the openings in the skin caused by bites become infected with the larvae of the Habronema stomach worm.

Control of external parasites should be a major focus of barn management. In no particular order, here are some actions you can take to help make yourself and your horse more comfortable at the barn.

Topical fly spray: These products are used to repel flies to keep them from landing on your horse. A number of chemicals are often used, most commonly Pyrethrin and Permethrin, in available products. Pyrethrin is derived from Pyrethrum, which comes from certain species of chrysanthemum plants. Permethrin is a synthetically-produced insecticide. Both Pyrethrin and Permethrin paralyze the insect’s nervous system. Flies will regain use of their neuro-systems after contact with Pyrethrin, but Permethrin is often mixed with synergists that will kill flies.

Common synergists include Piperonyl Butoxide and Bicycloheptene Dicarboxamide. The synergists inhibit the fly’s ability to recover use of its neuro function. Both Pyrethrin and Permethrin are restricted-use chemicals per the EPA and considered to be “relatively” non-toxic to mammals. While these compounds may be okay for your horse, Pyrethrin is known to be fatally toxic to fish and moderately toxic to birds and bees. Permethrin is fatal to cats and fish and highly toxic to birds and bees.

At Enviro Equine & PET, we do not feel comfortable spraying Permethrins or Pyrethrins on our horses either for their health, our health or the health of our barn cats or the birds and bees in our environment. These are the reasons why you will not find either of these chemicals in our Fly Spray Plus. Instead, we rely on a proven combination of apple cider vinegar, lemongrass, peppermint essential oils and camelina oil to repel flies. Safe for your horse, safe for you and safe for the environment!

Feeding omega-3 fatty acids: Horses with allergies to biting insects are actually allergic to the saliva that the insect injects while biting. Omega-3 fatty acids have been shown in research to support a more reasonable response to inflammation. Horses allergic to culicoides biting insects were found to have reduced reactions and less skin inflammation when they were fed omega-3 fatty acids in their diet. In addition to moderating inflammatory response, omega-3 fatty acids also support a great coat and healthy skin. OmegaBalance from Enviro Equine is a wonderful source of plant-based omega-3 fatty acid from camelina oil and may help support horses sensitive to biting insects.

  • Good manure management: Flies lay their eggs in manure, so make sure that you pick stalls at least once a day and dispose of manure away from the barn in well-managed manure heaps.
  • Fly predators: Consider using these harmless parasitic wasps in areas where manure is stored, damp areas and other places where flies like to congregate to lay eggs. The wasps feed on the fly larvae that emerge from eggs.
  • Fans: Keeping air moving makes it hard for insects to fly. However, be careful if using box fans as these have been linked to numerous barn fires.
  • Remove standing water: Mosquitoes breed in standing water, so ensure that all containers that may hold rain water are emptied frequently or stored upside down.
  • Fly masks/sheets/leg protection: Using fly masks can keep flies away from sensitive eyes, and sheets are useful for particularly sensitive horses. Sheets are often light in color as research has shown that certain flies, such as deer flies, are attracted to black and brown horses. Other research suggests that zebra stripes are a good defense against flies as they appear to be confused by the stripes.
  • Turnout time: Avoid turning horse out at dawn and dusk when biting insect levels can be at their highest.
  • Fly traps: While often stinky, the bag traps do attract and collect flies. Traps exist that appear to be very effective and that do not result in the stench commonly associated with these forms of fly control. Sticky paper strips are also effective in some areas, however other wildlife can get caught on them including birds trying to eat the stuck flies.

With careful barn management a lot can be done to make your horse’s life more comfortable during fly season. To learn more about Fly Spray Plus and Omega Balance.