Eye Issues in Foals – Vet Guide 2025 🐴👁️

By Dr Duncan Houston, BVSc

Introduction

Foal eyes are remarkably sensitive—vulnerable from the moment they open to the environment. A healthy beginning depends on early detection, proactive care, and expert veterinary guidance. In this 2025 veterinary guide, I, Dr Duncan Houston, walk horse owners through recognizing, diagnosing, and managing foal eye issues—from birth anomalies and trauma to infections and post-natal complications.

Why It Matters: Early Detection Saves Sight

• Fragile ocular tissues: Foal eyes are thinner and more susceptible to injury or infection—issues can escalate to serious damage within hours.
• Silent warning signs: Subtle swelling, excess blinking, or discharge may be the only alerts to underlying disease.
• Proactive vs reactive care: Early treatment often yields dramatically better outcomes—and preserves vision.

Routine Newborn Eye Exam at 12 Hours

It's recommended every foal receive a comprehensive vet assessment—**including ocular evaluation—within 12 hours of birth**. This check confirms the eyes are structurally sound, free from trauma, and responding normally to light.

(Derived from Texas Farm Bureau Radio Network, May 23, 2016)

What to Watch For at Birth

1. Eyelid and Periocular Swelling

• Even mild puffiness around the eyelids signals potential irritation or fluid buildup.
• Foals squinting or blinking often indicates discomfort—prompt vet evaluation is essential.

2. Discharge from the Eye

• Watery, mucoid, or purulent discharge is never normal—serious infection can advance rapidly.
• Any tear color change or flow pattern warrants immediate attention.

3. Eyelash Position & Blinking Patterns

• Prolapsed or drooping eyelashes can irritate the cornea, scratching the surface.
• Observe for asymmetry—excessive blinking in one eye is a key red flag.

(Observation tips from Dr Dennis Brooks via Horse.com)

Common Eye Problems in Foals

A. Birth-Related Trauma & Hemorrhage

Lacrimal and conjunctival vessels may rupture during birth, causing minor hemorrhages. These usually heal without issue, but monitoring is vital.

• Subconjunctival bleeding may appear as red patches in the white of the eye.
• No systemic illness—resolves in 48–72 hours.
• If bleeding persists or foal appears uncomfortable, contact your vet.

B. Corneal Ulcers & Surface Injuries

• Exposure to straw, bedding, or environmental contaminants can easily scratch a foal’s delicate cornea—**ulcers form quickly.**
• Symptoms include cloudy patches, squinting, eye rubbing, or pupillary constriction.
• Left untreated, ulcers may progress to infection, melting ulcers, or scarring—leading to vision loss.

(Noted by Dr Steve Roberts)

C. Congenital Abnormalities

• Foals may present with cataracts, microphthalmia (small eye), or globe deviation.
• Typically detected at birth and require referral to ophthalmology for confirmation and prognosis.

(Outlined by Dr Nancy Loving)

D. Secondary Eye Problems in Sick or Dehydrated Foals

Sickness compromises foal immunity; plus, sunken eyes from dehydration may draw in hairs and bedding, irritating the cornea.

• Persistent tearing, squinting, or discharge in a sick foal demands an ocular check.
• Hydration, environment, and full ocular inspection are part of a thorough exam.

Diagnostic Approach for Foal Eye Concerns

1. History & Presentation: Onset timing, dam's health, birthing difficulties, environmental factors.
2. Physical Exam: Inspect eyelids, lashes, discharge; note blink symmetry and eyelid tension.
3. Fluorescein Stain: Detects corneal epithelial defects or ulcers.
4. Slit-Lamp & Direct Ophthalmoscopic Exam: For deeper visualization of the anterior and posterior eye structures.
5. Tonometry: When feasible, to rule out pressure-related conditions like glaucoma.
6. Culture & Cytology: For discharges that suggest infection—or if infection is suspected.
7. Referral: Critical when congenital issues, deep ulcers, or surgical interventions are indicated.

Treatment Options for Eye Conditions in Foals

1. Corneal Ulcers & Scratch Management

• Topical antimicrobial drops/ointment (e.g., chloramphenicol, tetracycline) q4–6h.
• Atropine 1% to relieve iris spasms and pain.
• Systemic NSAIDs (flunixin, meloxicam) for comfort and to reduce inflammation.
• Serum or anti-collagenase agents for melting ulcers.
• Protective mask or rolling the foal sheath-side to prevent accidental ocular contact.
• Emergency referral for deep or non-healing ulcers.

2. Management of Congenital Conditions

• Cataracts or structural issues may be mild—supportive care is often adequate.
• Severe anomalies may need surgical correction or lifelong management.
• Frequent evaluations ensure early intervention potential.

3. Addressing Secondary Ocular Irritation

• Resolve primary illness—hydration, antibiotics, colostrum failure correction.
• Contain bedding/dust and ensure safe bedding choice—low-dust shavings over straw.
• Add topical ocular lubricants to minimize friction from dusty strands.

4. Treating Eyelash or Eyelid Irritation

• Episodic hair trimming may relieve lash rub.
• In persistent cases, eyelid suturing to rotate edges is an option—but only under vet care.

Prevention & Daily Monitoring

• Indoor birth stalls should be clean, dust-reduced, and low-stress.
• Remove sharp edges from stall hardware where foals might injure themselves.
• Daily glance checks—look for tearing, eyelid swelling, asymmetry.
• Keep fly control measures in place—masks and sprays can help reduce eye irritation.
• Ensure newborn foals receive proper colostrum to bolster immunity.

Case Example & Timeline

Case: A 2025 Thoroughbred colt born in a straw stall displayed mild eyelid swelling and intermittent blinking within 12 hours.

1. Hour 12: Eye exam finds minor subconjunctival hemorrhage; no corneal lesion initially detected.
2. Hour 24: Increased tearing, mild ulcer via fluorescein stain.
3. Treatment begun: Topical antibiotics, atropine q12h, systemic NSAIDs.
4. Day 3: Ulcer healing with no pain behaviors; swelling resolved.
5. Day 14: Full recovery with no scar detected; colt cleared for turnout.

This timeline underscores how rapid response prevents escalation.

When to Dial the Vet—Key Triggers

• Visible eye swelling, tear staining, discharge, or asymmetrical blinking.
• Corneal cloudiness, scratch behavior (rubbing, head shaking).
• Foal with concurrent illness—dehydration or infection increases ocular risk.
• Birth trauma or suspected eyelid abnormality.

Conclusion

Foal ocular health is delicate yet manageable with early vigilance. From minor hemorrhages to serious ulcers or congenital issues, swift veterinary assessment and proactive treatment protect vision and wellbeing.

When in doubt, don't wait—reach out to Ask A Vet via AskAVet.com or our app for experienced advice and support. Our team is ready to review photos, interpret symptoms, and guide you through every stage of foal eye care. 🩺📱