Lara knew something was wrong as soon as her mare came to the gate. Allegra’s lower eyelid was hanging loose and blood oozed from what looked like a fresh wound. The mare squinted as she faced the morning sun. Lara walked the mare into the shade of the barn and called her veterinarian.
Dan’s gelding was squinting slightly one Sunday morning, and tears trickled from his left eye. Dan rinsed the eye with cold tap water, but the gelding didn’t seem to be in any discomfort. An emergency call to the veterinarian would be costly on a Sunday, so Dan decided to wait a few days and let nature take its course. After all, money was tight. “It will probably heal on its own,” he reasoned.
Only one of these stories ends happily. It’s not hard to guess which one.
“Equine eye injuries always warrant a call to your veteri-narian,” says Alyssa Warneke, DVM, with the Myhre Equine Clinic in Rochester, New Hampshire. “I’ve worked on many cases where inappropriate evaluation of a seemingly minor issue, like a small lesion, has led to infection and complete loss of vision.”
The appeal of a wait-and-see approach is clear. And it isn’t just about avoiding a hefty veterinary bill. Dan’s horse didn’t seem to be in any distress---other than squinting, he behaved normally. But don’t forget that horses are, by nature, stoic. They’re hardwired to hide weakness from the rest of the herd and, of course, from predators. It stands to reason that a horse with vision problems will try to carry on as if nothing is amiss. And that means your horse’s eye trouble could be worse than he is letting on.
Signs of trouble
Many eye injuries are obvious. Your horse greets you at the gate, like Lara’s mare, with a lid hanging or an eye swollen shut. Sometimes, however, more subtle signs of eye trouble might escape your notice. Knowing what they are and why they matter will help you spot trouble as soon as possible. Investigate further and call the veterinarian if you see any of the following signs.
• Swelling of either of the eyelids, the tissues that surround the globe or the head around the eye.
• A lack of symmetry: A horse’s eyes are roughly the same size, so if one eye appears suddenly smaller than the other, it may have sunk deeper into the orbit.
• Squinting or frequent blinking.
• Reluctance to go from dark to bright areas.
• A constant stream of tears.
• White, yellow or green discharge.
• Head shyness or sudden spookiness.
• Cloudiness or change in color of the globe.
• Frequent rubbing of an eye. Check the inside of your horse’s knees for moisture if you’re unsure: That’s typically where he’ll rub his eyes.
• An unusual eyelash angle: Normally, both sets of a horse’s eyelashes extend outward perpendicular to the eyes and just about parallel to the ground. If the lashes of one of a horse’s eyes point downward, it could be an indication of subtle swelling.
Quick course on eye emergencies
Few things are more disturbing than discovering your horse has had some sort of eye trauma, but even if the situation doesn’t appear dire, it’s always a good idea to call your veterinarian for advice. Here are some of the most common equine eye injuries.
Foreign objectin the eye
How it happens: All sorts of things can get in your horse’s eyes---from fragments of hay to grit to bits of wood, twigs or burs. Foreign objects tend to make the eye tear profusely and sometimes cause the lids to swell shut.
Signs: Excessive squinting and tearing of an eye. A horse may be reluctant to let you examine the eye, and even if you can, you may or may not be able to see the object.
What to do: Bring your horse into the barn or an area protected from the sun, insects and wind. Call your veterinarian immediately. Try to keep the horse calm and prevent him from rubbing the eye. As you wait for the veterinarian, don’t try to remove the offending object, particularly if it is embedded, because you may exacerbate the damage.
Treatment: The veterinarian will remove the object, flush the eye and examine it for any corneal defects that could result in ulceration. Follow-up care may include daily flushing and topical antibiotics.
Orbital bone fracture
How it happens: Fractures of bones around the eye are most likely to occur when a horse rears and strikes his head on the ceiling, trailer or other object, or as a result of a kick to the head by a pasturemate. Occasionally, orbital bone fractures occur in falls or trauma to the poll rather than the eye itself. The frontal bone and the zygomatic arch (the prominent bony process above your horse’s eye) are most prone to injury.
Signs: Severe swelling in the area surrounding the eye. There may be an open wound but not necessarily.
What to do: Move the horse into a confined area and seek veterinary assistance---orbital fractures can interfere with a horse’s sinus function and breathing. The veterinarian will examine your horse’s face for asymmetry and will likely take x-rays in the field to determine the extent of the damage.
Treatment: You can’t put a cast or splint on a face, but you can limit a horse’s activities to allow the bones to heal. For some horses, stall rest and pain relief may be that’s all that’s necessary. In severe injuries, however, large pieces of bones may need to be stabilized surgically and/or small, loose bone fragments may need to be removed from the fracture site to prevent infection and encourage healing.
How it happens: Injuries to the eyelid can occur when a horse encounters tree branches, protruding objects or sharp-edged fences, walls or other structures in his environment.
Signs: Obvious trauma to the area, most likely with profuse bleeding.
What to do: Move your horse into a quiet area out of the sun and call your veterinarian.
Treatment: Eyelid lacerations are always serious but tend to heal well if treated promptly. Your veterinarian will administer a local analgesic to numb the area and, depending on your horse’s temperament, sedation. Your veterinarian may use absorbable sutures if she can but will probably want to schedule a follow-up visit regardless. A lacerated lid can disrupt the distribution of tears over the cornea, leading to an ulceration, so you’ll need to be vigilant in monitoring the eye even after the lid repair is made.
How it happens: Corneal scratches or abrasions can result from trauma to the surface of the eye or when grit or a foreign object becomes trapped under an eyelid. Corneal injury can lead to ulceration.
Signs: A corneal injury will cause squinting and profuse tearing, and the horse will be particularly sensitive to light. If an ulcer has formed, he is likely to be in obvious discomfort---agitated or very withdrawn---and unwilling to open the eye at all. If you’ve ever had a grain of sand or dust work its way into your eye, you know how painful it can be.
What do to: Move the horse into the barn. Do not apply anything to his eye, even if you have medication leftover from treating a similar injury. Without a diagnosis, it’s impossible to know if a product will help or make the situation worse. For instance, using a steroid cream on an eye with a fungal infection can lead to loss of the eye.
Treatment: Prompt treatment is necessary to save the horse’s vision. The veterinarian will flush the eye and perform a fluorescein dye test to determine the location of the ulcer. If it’s minor, it will likely be treated with topical medication. More serious ulcers may require a subpalpebral lavage system---an ophthalmic catheter that delivers topical liquid medication to the surface of the cornea---for easy administration of medication. Treatment focuses on inhibiting the breakdown of the cornea, warding off infection with antibiotics and/or antifungal medication, and minimizing pain and inflammation. A fly mask or ophthalmic hood is used to protect the eye from further irritation or injury.
Reduce the risk
Pretty much the same measures you take to generally protect your horse from injuries and illness will also help keep his eyes safe. But it’s worth giving some thought to potential eye hazards and doing what you can to minimize them. In fact, eye injuries are some of the easiest to protect your horse from, with just a few simple steps.
• Inspect your barn and other farm structures for eye hazards. Dedicate an hour to walking around your property with equine eye safety in mind. Be on the lookout for broken bucket snaps, bungee-cord hooks and protruding nails, all of which are infamous for causing injuries. If your horse likes to chew, pay particular attention to his plastic feed bin or bucket---hard polymers can cause nasty eye injuries when frayed. Use a flashlight to examine the boards of all of your enclosures for splinters and splits, and run your hand over surfaces to feel for protrusions. Do similar checks of trailers, paddocks and run-in sheds. At least once per season and after every storm, check your wood fencing for splinters, nails that work loose and downed tree limbs.
• Discourage through-the-fence grazing. Horses who push their heads through the lower boards or wires of fences to reach tempting grass can bump and injure their eyes in the process or as they pull back through. If your horse thinks the grass is greener on the other side of his fence, provide more forage inside his enclosure and consider reducing the temptation by mowing a 10-foot swath of grass short on the other side of the fence. A good deterrent for cross-fence grazing is adding electric tape or braid between the rails.
• Control prickly weeds in your pastures. Check your pastures for prickly bushes, weeds, downed limbs, and burdock plants. Burdocks are a member of the thistle family used in herbal teas and to treat topical skin conditions, but if they end up in your horse’s forelock those potentially beneficial uses won’t be foremost in your mind. In addition to posing a grooming/detangling challenge, burs that get caught in a horse’s forelock can break up and end up in his eyes, causing ulcers.
• Reduce exposure to insects. Flies are drawn to the moisture in and around equine eyes, and, in addition to being a nuisance, they can cause irritation that leads to eye problems. They may cause a horse to rub his eyes, which can result in abrasions and/or conjunctivitis, an inflammation or infection of the membranes lining the eyelids. Protect your horse with fly repellent---roll-on or wipe products are made for use on the face or delicate areas---and consider fitting him with a fly mask that not only serves as a barrier to insects but also offers UV protection. Minimize the fly populations on your property by composting manure and cleaning paddocks daily.
• Adopt eye-friendly management habits. Remember how vulnerable your horse’s eyes are to windborne dust and debris. If the wind kicks up when you’re out riding, slow to a walk or stop until the air clears, giving your horse a chance to lower his head and/or close and protect his eyes. Back at home, keep your horse’s eyes in mind when you feed hay---a rack mounted high enough to keep his legs safe is likely to be so high that dust and hay particles will fall in his eyes as he eats. Feeding hay from the ground is safer for his eyes and better for his respiratory health.
• Be careful when working around your horse’s head. “I’ve seen eye injuries caused by the owner accidentally hitting the horse in the eye with the tail end of a rope,” says Warneke. Most of us are not trick ropers … we do the best we can. When learning to use new equipment, though, especially ropes or dressage whips, practice on fence posts and the like. Don’t use your rope or whip near your horse until you can hit a small target on the fence. And take your time when pulling off your horse’s bridle or halter so that the straps and buckles clear his eye area safely.
Your horse’s eyes are the window to his world. While you can’t protect him from every mishap, spot checks on his environment and knowing what to do if he has an eye emergency go a long way toward preserving his vision for a lifetime.
A persistently watery eye
Sometimes copious, persistent tears signal a common and usually harmless equine eye problem: a blocked tear duct.
Technically known as nasolacrimal ducts, these tiny passages allow tears to drain from the eye down through the nostrils. If the ducts become clogged with mucus or other material, tears collect and spill over the bottom lid of the eye.
To clear the blockage, a veteri-narian will run a small tube up through the horse’s nose and flush saline through the channel. After a tear duct is flushed, it may never become clogged again, but some horses are prone to blockages and it may be best to simply leave them. When that’s the case, however, it’s important to protect the area below the eye against scalding with a thin layer of petroleum jelly and to use a mask against flies, which will be drawn to the moisture.
This article first appeared in the May 2017 issue (#476) of EQUUS magazine