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Eye has Swollen Pink Tissue inside Corner

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    The third eyelid (nictitating membrane), is a pink sheet of tissue that passes over the eye like a windshield wiper,starting from the inside corner of the eyeball. It does this as a protective reflex. Growths or abnormalities of the third eyelid tend to appear as pink masses at the inside corner of the eye. Unlike dogs, horses do not develop classic “cherry eye”, a blockage of the third eyelid gland.

    Protrusion of the third eyelid over the eye can indicate a variety of other problems, including severe body-wide diseases like tetanus.


    Given the importance of your horse’s sight and the wide range of conditions that could be causing this, do not allow this condition to continue or worsen over time. Take a photo and send it to your vet. Protect the eye with a fly mask until your vet can evaluate the problem.


    Your vet will examine the eye in order to determine the structures involved, reach a diagnosis and recommend treatment. Sedation or nerve blocks may be required to properly evaluate a problem here.

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

    Author: Doug Thal DVM Dipl. ABVP


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