At Rustebakke Veterinary Service, we understand how vital vision is to your horse’s comfort, safety, and performance. Whether your horse is a working partner or a beloved companion, maintaining healthy eyes is essential to their quality of life.

Corneal ulcers—one of the most common and potentially serious equine eye injuries—require swift recognition and treatment. Left untreated, even a seemingly minor scratch can quickly escalate into a painful, vision-threatening condition.

This guide is designed to help horse owners better understand equine corneal ulcers, including what causes them, how they’re diagnosed and treated, and what to expect for recovery.

Equine Cornea: Understanding Its Role in Vision

What is the Cornea?

The cornea is the transparent outermost layer of the horse’s eye, essential for both protection and focusing vision. It consists of three layers:

  • Epithelium (outer layer): Acts as a protective barrier.
  • Stroma (middle layer): Provides structural support.
  • Endothelium (inner layer): Maintains corneal clarity.

Why Horses Are Prone to Corneal Ulcers

Horses are particularly susceptible to corneal ulcers due to:

  • Their large, protruding eyes, which are more prone to trauma.
  • Frequent exposure to dust, debris, and UV rays, increasing irritation risks.
  • The tendency to rub their eyes against objects, exacerbating minor injuries.

Read more about common eye problems in horses.

Causes of Corneal Ulcers in Horses

Traumatic Injury

Corneal ulcers can result from:

  • Scratches from hay, tree branches, or stall doors.
  • Kicks or accidental head bumps.
  • Dirt, sand, or foreign objects lodged in the eye.

Bacterial or Fungal Infections

Secondary infections can develop if an ulcer isn’t treated promptly. Fungal infections, known as keratomycosis, are particularly common in warm, humid environments. Learn more about corneal disorders in horses.

Equine Recurrent Uveitis (ERU) & Underlying Conditions

Chronic inflammation, such as Equine Recurrent Uveitis (ERU), can weaken the cornea, increasing ulcer risks. Additionally, conditions like dry eye syndrome or tear film abnormalities can contribute. Explore more about uveitis in horses.

Recognizing the Symptoms of Corneal Ulcers

Common Signs of Corneal Ulcers

Early recognition of symptoms is crucial for effective treatment. Look for:

  • Squinting (blepharospasm) or excessive tearing (epiphora).
  • Redness and swelling around the eye.
  • Cloudiness or white spots on the cornea.
  • Increased sensitivity to light (photophobia).
  • Mucopurulent discharge (yellow or green).

When to Call Your Veterinarian

Immediate veterinary attention is necessary if:

  • Symptoms persist for more than 24 hours.
  • The horse’s eye appears cloudy or ulcerated.
  • There is severe pain, excessive discharge, or signs of vision loss.

Request an appointment for an equine eye exam.

Diagnosing Corneal Ulcers in Horses

Veterinary Examination

A thorough veterinary examination is essential for diagnosing corneal ulcers. This includes:

  • A detailed eye exam with an ophthalmoscope to assess damage.
  • Evaluation of intraocular pressure (IOP) to rule out glaucoma.
  • Schirmer tear test to check tear production.

Diagnostic Tests

Further diagnostic steps may include:

  • Fluorescein Staining: A fluorescent dye highlights corneal defects.
  • Cytology and Culture: Determines if a bacterial or fungal infection is present. Learn about corneal ulcer cytology.
  • Ultrasound or Advanced Imaging: Used for deeper corneal ulcers or perforations.

Treatment Options for Corneal Ulcers

Medical Management for Uncomplicated Ulcers

For uncomplicated ulcers, medical management often involves:

  • Antibiotic eye drops (e.g., neomycin-polymyxin-bacitracin) to prevent infection.
  • Pain relief with atropine drops to dilate the pupil and NSAIDs for inflammation.
  • Anti-fungal therapy if fungal keratitis is suspected.
  • Protective eye masks to prevent rubbing and further damage.

Discover more about corneal ulcer treatments.

When Surgery is Needed

In cases of deep or non-healing ulcers, surgical intervention may be necessary:

  • Conjunctival grafts or corneal transplants to promote healing.
  • Third eyelid flaps or temporary tarsorrhaphy to protect the eye.

Read about treating corneal ulcers.

Recovery and Prognosis

Expected Healing Time

  • Superficial ulcers: Heal within 7-10 days with proper treatment.
  • Deep or infected ulcers: May take weeks to months and require surgical care.

Preventing Complications

To prevent complications:

  • Strictly follow medication schedules and keep the eye protected. You may be putting eye drops in nearly round-the-clock for severe cases- it’s critical to stick with it.
  • Regular veterinary checkups to monitor healing progress.
  • Address any underlying conditions like dry eye or recurrent uveitis.

Long-Term Vision Outlook

With early intervention, most horses recover fully. However, severe ulcers may result in corneal scarring or partial vision loss. Horses with chronic eye issues may need lifelong management.

Preventing Corneal Ulcers in Horses

Reduce Environmental Risks

  • Keep stalls and paddocks free of sharp objects.
  • Use fly masks to protect against debris and UV rays.
  • Avoid dusty bedding and hay that can irritate the eyes.

Monitor Eye Health Regularly

  • Conduct daily eye checks for squinting, redness, or discharge.
  • Schedule routine vet exams to detect early signs of corneal disease.
  • Address underlying eye conditions before they worsen.

When to Seek Veterinary Care

Signs That Require Immediate Veterinary Attention

Seek veterinary care if you notice:

  • Sudden eye swelling, cloudiness, or excessive pain.
  • Thick or colored discharge from the eye.
  • No improvement within 24-48 hours of treatment.

How Rustebakke Veterinary Service Can Help

At Rustebakke Veterinary Service, we offer:

  • Experienced equine ophthalmology care.
  • Advanced diagnostics and treatment options for corneal ulcers.
  • Emergency eye care available for severe cases.

Meet our veterinary team.

Corneal ulcers in horses are serious but treatable if caught early. Prompt veterinary care is essential to prevent complications. With proper treatment and monitoring, most horses regain full vision. If your horse is showing signs of an eye problem, request an appointment at Rustebakke Veterinary Service. We are here to support you and your horse through every step of the healing process.