Understanding How Horses See the World: A Deep Dive into Horse Vision
- May 20
- 5 min read
Updated: Jun 2
Have you ever wondered how horses see the world around them? Understanding the intricacies of horse vision can provide valuable insights into their behavior and well-being.
Did you know that horses have a panoramic field of vision of approximately 350 degrees? This ability allows them to detect predators and danger from a distance.
Wide Field of Vision
Horses possess a remarkable panoramic field of vision due to the lateral positioning of their eyes. They can see almost 340 degrees around them. This vast field enables them to detect movement from various directions. It allows horses to continuously monitor their environment, especially while grazing.
Blind Spots
Despite their extraordinary vision, horses have blind spots directly in front of and behind them. This means you should be cautious when approaching them from these angles, as they might not see you.
Monocular & Binocular Vision
Horses can use either one eye at a time (monocular vision) or both eyes together (binocular vision). This flexibility helps them focus on objects and better assess their surroundings.
Night Vision
Horses have a unique adaptation called the 'tapetum lucidum.' This reflective layer in their eyes enhances their ability to see in low light conditions, making them more adept at navigating in the dusk or dawn.
Horizontal Pupils
Their oval-shaped pupils help horses scan the horizon for potential threats. This structure allows for maximum light capture, crucial for spotting dangers.
Color Perception
Horses perceive fewer colors than humans do. They primarily see shades of blue and yellow. However, their vision is particularly well-suited for detecting movement, which is vital for their survival.
Protection for the Eyes
A horse's eyes are safeguarded by the same eyelids seen in humans, plus an additional nictitating membrane, or third eyelid. This whitish-pink layer is located beneath the other eyelids at the inner corner of their eye. It extends upward when necessary, shielding the eye from scratches and responding to inflammation. This added level of protection is vital for maintaining eye health.
This article talks more about how horses see. One key takeaway was to give them plenty of rein around obstacles, both in-hand and under saddle. This is because they need to raise and lower their heads to assess depth and navigate terrain.
Understanding Horse Behavior
Recently, Warwick Schiller wrote an article about touching horses between their eyes. While I respect his training methods, I feel he should emphasize that many of the horses he works with are magnesium deficient. This deficiency can contribute to spookiness and anxiety.
Owners of highly reactive horses should consider a magnesium supplement like Calm Mix. They can differentiate which elements of their horses' anxiety stem from mineral deficiencies versus behavioral issues.
The Blind Spot Dilemma
Schiller notes that horses generally dislike being touched between the eyes because of their blind spot. Establishing a solid relationship with your horse is crucial before attempting to touch this area.
For those following our journey with little Martha on social media, I have stopped trying to touch her between her eyes. This change has positively impacted our relationship. I've become more patient in the paddock, waiting for her to offer her muzzle and feet. I've adopted a 'no touching until invited' strategy, which seems to be fostering trust.
This is a link to that article on Facebook.
Common Eye Problems in Horses
Before discussing eye issues, it's important to note that some horse breeds, like Appaloosas, are more prone to blindness. We currently have a blind Appaloosa at Sound Advice. Contrary to popular belief, euthanasia is not inevitable for blind horses. It is entirely possible for them to live happy, safe, and long lives.
Our blind mare, Rose, is in her mid-30s. Her vision has diminished over the past ten years, and she has been blind for around six years. Rose has always been sensitive to light, so she wears a fly mask.
Even as her vision has deteriorated, she remains a safe and happy mount for our children. She lives in the familiar paddock she knew when she could see. We maintain a structured routine so she knows where to go for meals. We also play music or podcasts to help her assess our locations. Communicating verbally while handling her ensures she recognizes us.
Rose relies on her "seeing eye" companion horse. If she can't hear her, she will call out, and Kazrah circles back to guide her.
Here is my daughter in 2018 (during the drought) negotiating objects with our partially blind horse.
Here is the same horse today with her seeing-eye companion.
Signs of Eye Conditions
Horses can experience a variety of eye problems, some requiring prompt attention. Signs that a horse may have an eye condition include:
Clumsy behavior
Increased incidence of self-trauma (injuries)
Reluctance to move, especially when transitioning from light to dark spaces
Spooky behavior
Head shaking
Common Issues to Watch For
Eye Ulcers: Scratches or injuries to the eye surface can lead to ulcers. These can become serious if left untreated. Usually, they can be treated with topical antibiotics.
Equine Recurrent Uveitis (ERU): Also known as "moon blindness," this autoimmune condition leads to recurring inflammation and potential vision loss. It's notably prevalent in Appaloosas, who are eight times more likely to experience it and four times more likely to lose sight in one or both eyes.
Conjunctivitis: This condition involves inflammation of the conjunctiva, often caused by dust, allergens, or infections. Antihistamines typically treat it.
Cataracts: These cause clouding of the lens, impairing vision. In severe cases, surgery may be necessary.
Eyelid Lacerations: Rips or tears in the eyelid are common in horses and should be repaired quickly to avoid infections and further damage. Your veterinarian will often clean the wound and use stitches for minimal scarring.
Corneal Injuries: Injury from debris can cause scratches or deeper wounds that require prompt attention.
Sensitivity to Light: Some horses develop photophobia, making them uncomfortable in bright conditions. Fly veils can improve their comfort significantly.
Entropion: This condition occurs when the eyelid edges turn inward, causing eyelashes to rub against the eye surface. In foals, it appears as a congenital defect, while in older horses, it may develop from chronic irritation or muscle spasms. Left untreated, it can lead to serious eye issues.
Blepharitis: Inflammation of the eyelids can stem from various causes, including dermatitis, conjunctivitis, or irritants. Your veterinarian may recommend medications and cleaning routines.
10. Eye Parasites: Conditions like eyeworm disease (Thelaziasis) are transmitted by face flies and can occur worldwide. Fly control is essential for prevention.
For deeper insights into eye conditions in horses, you can find a good overview here:
Here are additional resources:
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