If you are parents to an Australian Shepherd or a Siberian Husky with two different colored eyes and wonder why it is and if it is rare. The condition is known as heterochromia in dogs. It is more common in certain breeds than most people believe. It can be found even in cats, horses, and humans.
Also, heterochromia usually enhances their features and makes them look different. Let us look at the different variations or types and what causes heterochromia in dogs.
Types of Heterochromia in Dogs
There are three types of heterochromia in dogs:
Complete Heterochromia
Complete heterochromia is a phenomenon in which the color of one eye appears to be entirely different from the other. It can be like one eye possesses a dark brown color, while the other could be a bright shade of blue. It is also known as heterochromia iridum in dogs.
Sectoral Heterochromia
Sectoral heterochromia, as the name suggests, is an occurrence in which part of the dog’s iris appears to have a distinct color, and the rest of the eye is a different tone of some other color. It is a mixture of different colors within a single eye.
Central Heterochromia
Central heterochromia is also a unique characteristic found in dogs. In this phenomenon, the center of one or both eyes reveals a different tone than its outer part. Collectively, it portrays a blend of colors that sometimes serves as a treat to watch.
Causes of Heterochromia in Dogs
According to an article by Hill's Pet Nutrition, the absence of pigment melanin typically causes heterochromia in the iris (colored part of the eye). The iris in most dogs contains massive amounts of melanocytes, which give it a more golden brown or dark color. Heterochromia can be hereditary and is passed down through genetic makeup or acquired, meaning it can occur later in life.
Genetics
Dogs with blue eyes have a genetic mutation in the genes that regulate the concentration and distribution of melanin. In a study published by PLOS Genetics, genetic testing of dogs revealed genetic mutations associated with blue eyes and heterochromia in Siberian Huskies. And when these genes are passed on to the puppy from its parents, the condition is genetic.
Injury or Trauma
Heterochromia may also occur later in life from an injury or trauma to the eye. An accident can lead to a change in the color of the eyes of dogs. This type of heterochromia is known as traumatic or acquired heterochromia.
Health Factors
Heterochromia in dogs may be caused by health problems including glaucoma or uveitis (inflammation in the interior of the eye), an underdeveloped optic nerve, cataracts, or retinal dysplasia. These conditions can change the iris pigmentation, resulting in an eye changing color. Consulting your veterinarian is a must in these situations.
Top 5 Common Breeds with Heterochromia
Heterochromia can occur in dogs of any breed. However, certain breeds are more prone to heterochromia, and the five most common breeds with heterochromia include:
Siberian Husky
Siberian Huskies are the most common breed of dogs with heterochromia. The Huskies have complete heterochromia; the pattern features one blue eye and the other brown.
Australian Shepherd
Australian Shepherds are another breed prone to heterochromia. This particular breed often grows heterochromia with variations in eye color. The phenomenon looks eye-catching and unique.
Shetland Sheepdog
It is known that Shetland Sheepdogs have a persuasive look. They may undergo heterochromia occasionally. The heterochromatic eyes of Shetland Sheepdogs make them appear more attractive and enticing.
Border Collie
Border Collies are intelligent and known for their herding abilities. This breed can also develop heterochromia, which can be hereditary or acquired. It makes them extremely beautiful.
Dalmatian
Dalmatians are also known to exhibit heterochromia. They have a distinctive feature of black spots, and with the phenomenon of different colored eyes, they look charming.
Is Heterochromia More Common in Purebred Or Mixed-Breed?
Heterochromia is a well-known phenomenon in purebred and mixed breeds. However, certain purebreds are more inclined to have this characteristic.
Is Heterochromia Harmful to Dogs?
Fortunately, heterochromia is not harmful to dogs. The condition is usually benign and does not cause health problems in dogs, and they can have normal lives just like any other animal. It is a unique trait and can be an added advantage as a cosmetic feature for the dog.
Veterinary Exam
Though heterochromia is harmless, it is still advisable to get them checked with the veterinarian, especially in the case of any injury that develops heterochromia eyes in dogs.
Medical Issues
In some cases, heterochromia can be a sign of underlying health issues or ocular disorders. The diagnosis of the cause is essential. The veterinarian may collect your dog’s medical history of past injuries or any other medical condition and their breed and family history.
Genetic Testing
Veterinarians often recommend genetic testing where the medical issues are ruled out, and heterochromia may be congenital. Genetic testing applies to identifying specific genetic mutations related to heterochromia through DNA analysis. Getting your pet examined regularly for any change in eye color ensures they live a healthy and happy life.
Treating Underlying Health Issues
When heterochromia is a symptom of an underlying health issue or eye disorder, the treatment centers on identifying the root cause. The treatment program may comprise prescription medicines by the veterinarian to manage conditions like glaucoma or uveitis. Moreover, surgery may be required to restore eye function or improve eye damage in case of painful eye injury.
It is essential to understand that you cannot treat heterochromia, but associated health issues are addressed and managed to ensure the dog's wellness.
Conclusion
Heterochromia is when different colored eyes are found in dogs. It can add to the beauty of the overall dog’s appearance. However, you must not neglect the condition if it occurs due to underlying health issues and recognize if it's congenital or acquired to keep your dog healthy and happy.
Frequently Asked Questions
Can heterochromia be passed down to puppies?
If heterochromia in the dog is hereditary, it can be passed down to puppies through genetic makeup.
Is heterochromia more common in certain breeds?
Certain breeds, like Australian Shepherds and Siberian Huskies, are more likely to have heterochromia.
Does heterochromia affect vision in dogs?
More often, hereditary heterochromia in dogs does not affect the eyes or the vision, but an underlying issue can.
Why do some dogs have one blue eye?
Heterochromia in dogs, which is the absence of pigment melanin (gives dark or golden brown color to the iris part of the eye) causes one eye to emerge blue or bluish-white.
Are there any famous dogs with heterochromia?
Yes, famous dogs like Max the Cocker Spaniel and Bowie the Husky are widely known for their heterochromatic eyes.
How rare is heterochromia in dogs?
Heterochromia is more common in certain breeds. It is mostly seen in dog breeds with dappled, merle, or white color coating.
How rare is sectoral heterochromia in dogs?
Sectoral heterochromia in dogs is more common in certain breeds, such as Border Collie, Australian Shepherd, and Shetland Sheepdog.