Blue-eyed horses are not something you see every day, but they do exist. While some people are startled by their eeriness, others find them mesmerizing. They sure make for a special sight, and because of that, a number of myths and beliefs circulate about them to this day.
Many people tend to associate blue-eyed horses with light sensitivity or a crazy temperament. But how much truth is in these allegations and why do horses have blue eyes?
Blue eyes are often seen in horses with white markings or dilution coat colors such as cremellos, perlinos, palominos, or buckskins. The cream gene responsible for these coat colors also makes the eyes less pigmented. While blue eyes are more common in some breeds, they can appear in virtually any horse breed.
Horse breeds with blue eyes
As blue eyes in horses are closely linked with coat color, they most often occur in breeds displaying these white or cream type coat colors.
The most common horse breeds with blue eyes are the Quarter Horse, Tennessee Walking Horse, Paint Horse, and Appaloosa. Other breeds frequently wearing blue eyes are the Akhal Teke, Gypsy Vanner, or Miniature Horse.
There have also been reports of an increasing number of Thoroughbreds and Arabians having blue eyes. However, this is still an infrequent occurrence.
Horse coat colors and blue eyes
Whether a horse will be born blue-eyed or not is more dependent on coat color than anything else. Double-dilute colorations will always come with blue eyes, like the cremello and perlino. These are horses with a chestnut, bay, or brown base color that has been diluted twice by the cream gene.
Single-dilutes like palominos or buckskins can also have blue eyes, although less frequently. Blue eyes are scarce in horses with base colors such as bay, chestnut, or black, but not unheard of. These horses will almost always have white markings.
Pinto and appaloosa colors are also associated with having blue eyes. The chances of this happening are even higher in horses with frame overo, splashed white, or sabino patterns. What’s more, blue eyes can be quite common in horses where white markings spread onto one or both eyes, like in “white-faced” horses.
Are horses with blue eyes rare?
Horses with blue eyes are quite uncommon. There hasn’t been a study to estimate what percentage of the horse population has blue eyes, but they are more common in certain breeds.
We can guess that there are definitely fewer blue-eyed horses than humans relative to the whole population, where this number is around 8-10%. Perhaps when the origins and genetics of this phenomenon in horses will be better understood, scientists will calculate a rough estimate.
It is no surprise however that blue eyes are such a rare occurrence in horses. Being a prey animal, a glowing pair of blue eyes would have been more likely to reveal horses to predators in the wild. Traits that decrease the chances of survival in a species are naturally selected out during evolution.
Common disorders of blue-eyed horses
Assumptions that horses with blue eyes see the world differently and are more prone to eye-ailments are common among horsepeople. Many also think that because blue-eyed humans are more sensitive to light, this must be true for horses too. However, science is telling a whole other story.
A study done in 2014 by American scientists has looked at the medical records of two groups of horses, one with eye ailments and one without. They found that blue-eyed horses were equally common in both groups and are no more prone to eye disorders than dark-eyed horses.
The only exception is ocular squamous cell carcinoma (SCC), which is the cancer of unpigmented skin around the eyes. Since many blue-eyed horses have unpigmented skin surrounding their eyes, SCC is often associated with this group. The condition is preventable by protecting horses from UV radiation with fly masks, sunscreen, and providing shade during peak hours.
So where did those myths and assumptions come from? Clearly, there must have been a few coincidences where misbehaving or diseased horses happened to have blue eyes. And since these were such unusual combinations, they were quick to start rumours.
Facts about horses with blue eyes
- Blue-eyed horses don’t see any differently to dark-eyed horses, they both have the same two-color (dichromatic) vision
- Heterochromia is common in Paint Horses and causes the horse to have mismatched eyes
- Two rare conditions where a single eye has two different colors are called segmental and central heterochromia
- The Blue-Eyed Horse Association (BEHA) registers horses with blue eyes regardless of breed and is committed to the study of these unique animals
- Horses with champagne coat colors will have greenish-blue eyes at birth that will darken as they grow
- The blue eyes of cream-colored horses are paler than those of horses with white markings
Frequently Asked Questions
What causes blue eyes in horses?
Blue eyes in horses and other animals are caused by a reduced number of pigments in the iris. This is the structure surrounding the pupil and the more pigments it has, the darker the eye color will be.
Are horses with blue eyes blind/deaf?
Horses with blue eyes are not blind and their eyes work just as well as horses with different eye colors. Blue eyed horses are also no more prone to diseases than any other horses.
There have been a couple of studies investigating deafness in Paint Horses with blue eyes. A recent paper published in 2019 has revealed a genetic link between the splashed white coat pattern, blue eyes and increased risk of deafness in this breed.
Are blue-eyed horses sensitive to light?
Although decreased pigmentation in the iris of blue eyes means more light will be entering the eye, this doesn’t cause light sensitivity in horses with blue eyes. The only structure that’s more sensitive to light in blue-eyed horses is any unpigmented skin around the eyes.