It won’t be wrong to say that horse vision is quite different from that of a human being. Equines see the world rather differently than we do. That difference is mainly due to the placement of their eyes along with their anatomy. This makes them react differently to various stimuli and a rider should be well aware of these reactions so he can cope with them, when needed.
In this article, we’ll guide you on equine vision and how the riding and training of your horse are related to it.
Horse Vision: The Visual Ability of Equines
There is a lot of debate on the visual ability of horses and how it affects riders. You see, most riders might know a thing or two about horse vision, but rarely does anyone know how it affects the riding process.
If the horse’s range of vision is less, how should a rider tackle that? What about peripheral vision? We’ll discuss all of this and a lot more as we move further.
Horse Range of Vision
Did you know that the horse’s eye size is the largest of all land mammals?
Also, many believe that the horse can actually see 360 degrees.
Now, is that true? Well, almost! Horse eye structure and position allow it to see almost 360 degrees. However, they can not see right in front of them for only a short distance, as well as directly behind them. This is the very reason expert riders recommend not to approach a horse from the back because it’s unaware of who or what is back there.
Not to mention, horse vision is 20% binocular only (which makes about 65 degrees in front of the horse) while the remaining 80% is monocular. This means that most of the surroundings of the horse are seen by one eye only! This is the reason why a horse has to change a little bit of his direction in order to look at something that catches his eye.
This lack of binocular vision makes some horses “spooky”, that is, they get spooked quite easily by a sudden movement in their surroundings. This can cause your horse to get scared if you catch it off-guard.
That’s why it’s important to gain a horse’s trust and to approach it from the side where it can see you clearly.
But here’s an interesting fact:
With such a wide range of monocular vision, horses can observe both its sides simultaneously.
The setback of monocular horse vision, however, is that an object that is perceived from one eye may look completely different from the other.
Up until a few years ago, it was largely believed that horses move their heads in order to bring objects into their binocular vision. Concurrently, it was believed that in order to look down, the horse lowers his neck. Consequently, when he has to look ahead, like in horse racing or jumping, the neck should be up and straight. However, a study published in 2010 showed that the position of the head is not associated with changes in horse vision.
Horse Blind Spots
It is worth noting that horses have two blind spots in their vision. These are the areas where your equine companion can not see anything. The first blind spot is right in front of the face making a 90 to 120 cm cone. The second one is right behind the horse, close to its tail. So when a horse jumps over an obstacle, there’s a lot of guesswork and calculation involved because right before the jump happens, the obstacle enters the horse’s blind spot. So, the horse is in fact jumping blindly!
If you’re jumping a horse, allow the horse to use his distant vision by raising his head a bit more than usual so that it assesses the jump properly.
Depth Perception in Horse Vision
Just because the eyes of a horse are on the sides of his face does not mean it would have bad depth perception.
We know that equine vision is largely monocular but it also has a 55 to 65-degree binocular overlap when looking at the front. This enables accurate depth perception for horses.
A very fine way to judge distances is to raise/lower and tilt the head of the horse so that he can perceive the depth accordingly. This can be accomplished by a fairly loose rein and giving freedom to the horse to move his head when judging distances.
Acuity in Horses
Acuity means sharpness in literal terms. The horses astonishingly have a “visual streak”. This means that when an object falls in this area, it is much better seen by horses than humans. Thus, the horse will raise or tilt its head so that the object falls in this visual streak region.
It is in fact not a pleasant feeling for the horse if something he wants to focus on is not in his visual streak, which may cause aggression. If something like this ever occurs, let the horse calm himself by roaming around and focusing things. Make him feel at home.
Motion Detection in Horses
Like most animals, motion is the first indication for horses that a predator is approaching. The peripheral vision first detects this motion where the visual acuity is quite poor. They can not see properly when an object suddenly enters this vision, so they tend to run, hoping that it’s not a predator.
After this initial instinct comes into play, they take a look back at what the object actually was. That might be the reason why your horse sometimes gets nervous on a windy day. Everything is moving around him, which makes him scared. He can’t differentiate between a thing moving because of wind and an actual threat.
That’s why it’s vital to have your horse trust you. That way, he will obey your command in such circumstances. One way to do that is to make yourself worthy as a leader in the eyes of the horse. Don’t seem panicked in front of your horse. If you stay calm in such circumstances, your horse will look towards you for leadership and guidance. Minimizing the threat with your trust is the way to go.
Blind Spots in Horse Vision and Its Behavioral Effects
As we discussed earlier, there are two blind spots in horse vision. The first one is right in front of the nose at about 90-120 cm and the other one right at the back.
Now the question is:
How do these blind spots affect a horse’s behavior?
Blind spots certainly have behavioral effects on the horse.
When an object lies in these blind spots, horses get anxious with the fact that they can’t see it.
It is thus, dangerous for humans to stand for a long time in a horse’s blind spot as the horse has no clue who or what is in there. The horse can become impatient when he loses the sight of his owner and may startle if he sees him on the other side.
There’s a possibility that the owner himself can be knocked out by the horse. At the back end, we should not forget that the horse has an extraordinary ability to strike with its hoof, which has the potential to do great harm. We should make sure to always approach the horse from the side where he can clearly see us. Try to always speak to the horse in a soothing voice when approaching him. This way, he would be aware of your presence and won’t get spooked.
Color Vision in Horses
According to research published in the Journal of Comparative Psychology, Horses are dichromats with red-green color deficiencies. So if you want to paint your arena so that the horse can clearly see obstacles, paint it blue and white rather than red and green. The colors blue and white are better seen by the horses.
In essence, a horse’s color perception is similar to a humans. Like humans, horses also have rods and cones in their eyes that detect different colors. But they perceive these colors in different intensities than we do.
Some people say that horses can not see colors but research has clearly proven otherwise. It might be right to say that horses do not see colors as clearly as we do, but they definitely see the world with colors. That is why the obstacles are colored using shades that are clearly identifiable by horses. This helps horses to verify the object and distinguish it from the background.
The only two colors that horses struggle with are red and green. So, you shouldn’t use those colors when it comes to objects used by your horse.
Light Detection in Horse Vision
Horses see objects in low light far better than we do. In the light that seems pitch black to us, the horse might still be able to see and perceive objects.
With that said, horses aren’t as good as us at adjusting to rapidly changing light. That’s why when we turn on the light in a barn, the horse might blink like crazy for some time.
It also explains why some horses are afraid to enter a tunnel or shadowy area. We must keep all this in mind that it’s not the fault of your horse that he sometimes refuses to do as you say. Try to gain the trust of your equine partner to make him feel relaxed when obeying your orders.
Day and Night Vision in Horses
The horse’s eyesight in the day is quite solid except for the fact that it can not differentiate between some colours like red and green. Sometimes, objects get merged with the background because of their colour. However, the fact that a horse can view almost 360 degrees is helpful.
At night, the vision of a horse is much better than humans. They are sensitive to low light and can thus see objects reasonably well.
Eye Disorders in Horses
Eye disorders are usually a major cause of concern whether it be humans or animals. Horses also attain many eye disorders. Some of them are as follows:
Keratitis is a serious disease that has the potential to threaten your horse’s vision. Usually, one eye is affected but certain cases have also been reported in which both the eyes are affected. In such circumstances, you should examine the eyes of your horse daily to see any change. If you do see a change, you should contact your vet for an appointment.
Common symptoms of keratitis include:
- Inflammation of the eyelids
- Ocular discharge
- Corneal oedema
- Watery eye
- Pupil constriction
Researchers believe that keratitis in horses occurs when a microbial agent incorporates in the horse’s eye.
The eye of a horse can slough off the cells that are damaged. This is how healing takes place in the cornea of a horse. To treat your horse, your vet will give him medicines so that he doesn’t go blind. If the treatment does not produce satisfactory effects, then surgery might be the last resort.
Breaks in the cornea (the transparent front part of the eye) that can cause inflammation are called corneal ulcers. A bacterial or fungal infection should be considered whenever a corneal ulcer develops. If bacteria are the cause, then it might be seen as a melting ulcer. Otherwise, a fungal infection may result in the loss of 25% vision, even if you treat it successfully.
The healing time for a horse suffering from corneal ulcer depends on how deep the ulcer is. Deep ulcers take more time to heal than superficial ones. Even though corneal ulcers might appear mild, they should be taken seriously as they can drastically affect the vision of your horse.
Symptoms of corneal ulcers are:
- Decreased vision
- Inability to tolerate sunlight
- Blue or cloudy cornea
- Red or swollen eye
The treatment depends on the depth of the ulcer. Superficial ulcers might be treated by broad-spectrum antibiotics. Atropine is used to dilate the eye whereas painkillers are given to relieve pain.
In melting type or deep ulcers, it will require more treatments on top of those that are already discussed. In a fungal infection, antifungal medication is prescribed whereas in severe cases, a corneal transplant from a healthy donor horse might be the only option.
Conjunctivitis, also referred to as pink eye, is characterized by the eye becoming pink or red. Drainage, discomfort and swollen eyes are also seen. There may be a viral or bacterial infection that might have caused the disease or it might be caused due to irritants in the environment.
Red and pink eyes are the most common symptoms of conjunctivitis in horses. Other symptoms of conjunctivitis include:
- Pain in the eyes
- Ocular discharge
- Eyes unable to open
The causes of conjunctivitis are:
- Systemic viral illnesses
- Upper GIT infections
- Nasal and sinus discharge
There are many reasons why your horse might be suffering from conjunctivitis and the treatment is given according to the diagnosis. If your horse is discharging pus from the eye, an antibiotic may be prescribed by the vet. This will be put in the horse’s eye. These antibiotics typically work quickly.
If an object is seen in the eye, it will be removed by the veterinarian, after which he’ll possibly give an antibiotic to your horse. On the other hand, eye drops are usually prescribed if the veterinarian finds that your horse has an allergy.
Horse Vision FAQs
The eyesight of a horse is very crucial. That’s the reason why horse owners are so concerned about their horse’s vision. Following are some of the questions equine lovers ask us about this topic.
How good is a horse’s vision?
The vision of a horse is quite good as it has both monocular as well as binocular vision. The binocular vision is about 55 to 65 degrees when a horse looks straight at the front. Monocular vision comes into work when the horse needs to look sideways. It is hard to imagine that a horse can see up to 350 degrees. Humans, in contrast, can not even see 180 degrees without moving their heads.
So in order to see predators, the horse’s eyes work just fine. Unless the predator approaches the horse from its blind spots, (the one in front of the nose and the other one right behind where the tail is situated) the horse can easily figure out where it is and can run for cover.
Can a horse see 360 degrees?
A horse can not see 360 degrees to be precise but can see around 350 degrees. About 20% of its vision is binocular that makes an angle of 55 to 65 degrees in the front. The remaining 80% of the horse’s vision is monocular.
There are two blind spots where the horse can’t see. Right in front where the nose is situated and right at the back where the tail is found. This consists of the 10 degrees that a horse is unable to see with a straight head pointing forwards. However, if the horse slightly moves his head towards the side, he is able to see the blind spot at the back too.
Humans should not approach the horse from its tail as it can’t tell whether it is a predator approaching or its owner. The horse can kick you with his powerful legs and the result might be quite brutal or even fatal.
Do horses have peripheral vision?
Yes, horses do have peripheral vision, which refers to the ability to view objects around you without moving your head. Like most animals, the eyes of the horses are placed on the sides of their heads. This enables the horse to see a full panoramic view around them. Equine vision consists of monocular as well as binocular vision. However, horses do have two blind spots. One right in front of their head about 3 to 4 feet. The second one is at the back.
The vision in which only one eye is used by a horse is referred to as its monocular vision. Due to this vision, the horse can assimilate his surroundings in a more generalized way.
Horses also have the ability to focus on an object with two eyes. This is called binocular vision. Using both monocular and binocular vision, the horse can steer his way to complete the task assigned.
Is it okay to look a horse in the eye?
It is preferred that you look your horse in the eye. This will help establish you as the alpha. At the same time, it’s also a great way of establishing a sense of warm trust with your horse.
While doing work with a horse, it is highly advised to look him straight in the eye as much as possible. The reason is that horses are very observant of their work and they study their surroundings quite well. So if you are on their radar, they are probably observing you too.