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Equine Health Resource

Eyes are Bothered by Flies

Code Green - Contact Your Vet to Obtain Useful Advice & Resources

Code Green - Contact Your Vet to Obtain Useful Advice & Resources

    Flies of different types love to bother horse eyes, and they commonly cause eye irritation. Flies can also transmit certain bacterial and parasitic diseases to the eyes of horses.

    Stable Flies are a seasonal problem in most areas and are usually worse in summer and fall. At certain times of year, Stable Flies are particularly drawn to equine eyes, especially the corners of the eye. They cause irritation that results in tearing and squinting and predispose to the development of corneal ulcers and conjunctivitis.

    No-See-Ums (gnats, Culicoides) can also attach the eyes and can cause severe irritation and itchiness.


    Given the importance of your horse’s sight, if you notice a problem with the eyes or cannot find a way to protect them from flies, do not allow this condition to continue or worsen over time. Assess your horse’s eyes carefully. If the eyes appears irritated, red, swollen, or if there is tearing or discharge contact your vet to discuss your findings and concerns.

    It is helpful to identify the type of flies that are bothering the horse’s eyes. Take a photo of the flies and share it with your vet.

    Prevention is key. This starts with a good fly control and manure management program at your facility. Apply a fly mask. In some cases, applying a fly repellent ointment around the eyes may be helpful.


    Your vet may know the insect species and their biology and may have recommendations on how to control or decrease the fly population at your facility, so to prevent the development of more serious eye problems.

    Helpful Terms & Topics in HSVGWritten, Reviewed or Shared by Experts in Equine Health

    Author: Doug Thal DVM Dipl. ABVP


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