Equine Insect Repellents For Horses

So-called “fly” or insect repellents help keep your horse comfortable and minimize his risk of exposure to insect-carried infectious diseases and health issues. Many common flies that pester horses belong to the family Diptera. Mosquitoes also belong to this family. Horse flies belong to a different family.

They Carry What?

Owners choose fly repellents for reasons beyond comfort of the horse. Some of the problems that flies can carry to a horse are caused by biting flies (including horse flies) and midges. These include equine infectious anemia (EIA), vesicular stomatitis (VS), and pigeon fever.

Anthrax can be carried by biting flies or through manual transmission by non-biting flies.

Sarcoids in horses have been suggested to be spread by flies. “Bovine papillomavirus (BPV), primarily types 1 and 2, is now considered the main etiologic agent of equine sarcoids,” according to the Merck Veterinary Manual. Researchers have found BPV in some common fly species, such as house and stable flies. They propose the link to flies and sarcoids in horses because there is an apparent predilection for sarcoid development at wound sites. “It has been proposed that flies may act as vectors as they move between wound sites on different horses,” noted the Merck Veterinary Manual.

Mosquitoes can carry many diseases to horses, including encephalitis (Eastern and Western equine encephalitis, or EEE/WEE). West Nile virus also can be carried to horses by mosquitoes.

Non-biting flies can also cause health issues such as conjunctivitis (pinkeye),

What About Ticks?

Pest repellents (insecticides) are also used to keep ticks off your horses. But make sure to read the label as all repellents don’t have the same ingredients. The label should say the product is active against ticks. Don’t assume that it is if the label doesn’t say so!

You can learn more about ticks and horses from this AAEP article. It is suggested that the key ingredients to look for include pyrethrins and synthetic pyrethroids (permethrin, cypermethrin, and resmethrin). There are others, so again, read the label!

Diseases that are carried by ticks include Borrelia burgdorferi (B burgdorferi) that causes Lyme disease. Ticks also can carry equine piroplasmosis and anaplasmosis to horses.

Active Ingredients of Repellents

With seemingly hundreds of choices when it comes to topical insecticides, so how do you decide which one to use? Read the label and check out the tips below!

For starters, look at the active ingredients in the product. Most contain some form of pyrethrins, which is the natural extract of Chrysanthemum flowers. Repellents also could contain pyrethroids. These are synthetic compounds (as mentioned above) that are designed to work like the natural pyrethrins. These chemicals—both the natural and synthetic—are useful for their insecticidal capabilities as well as being safe for use on most animals.

Because the ultraviolet rays of sunlight rapidly break down pyrethrin or its derivatives, insecticidal effects only last for a few hours. The addition of sunscreen might improve a product’s protection longevity. Again, read the label.

In some insect control products, piperonyl butoxide is added to improve effectiveness of the product by delaying breakdown of the chemical by insects.

Pyrethrin products come in a concentrate form that must be diluted or in a ready-to-use application. These products can be offered as a wipe, spray, or pour-on.

Permectrin CDS is a pour-on insecticide with FDA approval for use in horses. It can also be applied as a spray or with wipes.

Home-Made Products

Other popular insect repellents or home-made recipes for use on horses might include ingredients such as citronella oils, lemongrass, eucalyptus oils, or Skin-So-Soft. These aren’t as effective as the aforementioned insecticides, nor do they act as long in duration as pyrethrin-based products.

Final Words

No matter how you apply a product, it must be in contact with the hair. It is important to brush away mud, dirt, and grime from your horse’s coat before the application of any insecticide.

Sprays are safe to use on the torso and legs. However, when you apply fly spray to the horse’s face, only use a cloth or sponge. Be sure to keep the chemical away from your horse’s eyes. Don’t forget that anything that is wiped above the eyes could run into the horse’s eyes with sweat. That could cause the chemical to “burn” the cornea.

Read the labels on commercial products. If you are treating pregnant or lactating mares or young foals, ensure that it is labeled as safe to use for those individuals.

Also, be conscious of the proximity of other domestic animals when using these products. For example, permethrin is extremely toxic to cats.

And don’t forget the importance of fly masks, sheets, and leggings. Management of your property to prevent mosquitoes and flies from hatching can go a long way in preventing the next crop of insects from “bugging” your horses!