What is it about Aussies that causes them to have heterochromia? It all comes down to genetics. Those two different eye colors, which is also known as wall eye, is one trait of many in dogs that their mother and father canine can pass down. With two parents, a puppy's gene copies double.
Heterochromia is caused by a lack of the pigment melanin in all or part of one eye. In dogs with heterochromia, the lack of melanin causes one of their eyes to appear blue or bluish-white. Heterochromia in dogs is often hereditary, meaning it is passed through their genetic makeup.
The Australian Shepherd is one of a few dog breeds that commonly have two different colored eyes, called heterochromia. Aussies might have any combination of brown, blue, hazel, amber, or green eyes. Some Aussies even display more than one color within the same eye.
And it can show up in mixed breeds, too—provided they have a carrier of the blue eye variant in their ancestry. That said, the trait is still quite rare. In our DNA testing, we've found only about 5% of dogs to have the blue eye variant. Genetic variants may cause only one eye to be blue.
Blue eyes are not more susceptible to eye defects and disease but they are more sensitive to bright light (just as they are in blue-eyed people.) There is no clear association of blue eyes to deafness in Aussies; deaf Aussies virtually always have too much white on the head or are double merle.
Blue and light-colored eyed dogs commonly experience light sensitivity and a little shade can go a long way to make them more comfortable outdoors.
This term refers to a puppy bred by two merle colored Aussie parents. Many people are unaware, but when two merles (of any breed) are bred together, each puppy has a 25% chance of being born as a double merle.
As inbreeding is more unusual and less common for humans, the gene for heterochromia is typically masked by more dominant genes. However, if two people who both have heterochromia were to produce offspring, it is much more likely that their offspring will also have the condition.
Most dogs have brown eyes, but there are breeds with pale blue, speckled, golden, or hazel colored eyes. The rarest color of all is green. Dog eye color changes as they age. It often takes nine to 12 weeks for a puppy's eye color to settle.
The good news is that dogs can quite easily adapt to life with one eye and live long, happy, and completely problem-free lives. However, if your pet is having an eye removed, you'll need to offer whatever assistance you can to help make the adjustment to their new circumstances as smooth as possible.
Blue eyes, resulting from an absence of pigment in the iris, is common with pigment-associated deafness but is not, in and of itself, an indication of deafness or the presence of a deafness gene; however, in several breeds (Dalmatian, English Setter, English Cocker Spaniel, Bull Terrier), dogs (and cats) with blue eyes ...
Aussies are best suited for families with an active lifestyle and a large fenced yard. They need plenty of exercise and mental stimulation to prevent boredom. They can weigh between 35 and 70 pounds and have an average life span of 12-13 years.
The Aussie's desire to cuddle
Dogs in general are known for being happy, cuddly, sweet, and soothing for a human to pet. Some breeds are, by nature, more affectionate than others. While the Aussie will typically reserve cuddling for one person or a group of trusted people, sometimes he won't want to cuddle at all.
While two-toned eyes are certainly striking, there is no need to be alarmed. The condition is genetic and there is generally no need to worry. But dogs with heterochromia might also be linked to glaucoma, so if you suspect that there might be something wrong, definitely talk to your vet about all concerns.
Pups that are destined to have eyes that are very dark, almost black, will have dark irises of a midnight blue color from the beginning. In a puppy with split or marbled eyes part of the iris is dark like this pup's eyes, and the blue area is pale. This female from the same litter has eyes that stayed blue.
So, what did we find? In short, we discovered a genetic mutation, specifically a duplication of DNA sequence near ALX4 (a gene on dog chromosome 18 involved in craniofacial, skin, and hair follicle development) that explains why some dogs have blue eyes.
Human eyes have three different types of cones, which allows us to identify combinations of red, blue, and green. Dogs, on the other hand, have only two types of cones, which means they can only discern blue and yellow. As a result, dogs are red-green colour blind.
Cardigan Welsh Corgi
Like the dachshund, a Cardigan may have two blue eyes, one blue and one brown, or even both colors in one eye. These unique eye colors are most common in corgis with merle coats.
Heterochromia Causes. There are many types and causes of heterochromia. An infant can be born with it or develop it soon after birth. In these cases, it is called congenital heterochromia.
Finally, a marked sexual dimorphism was observed, as in females heterochromia is much more frequent than in males.
Dogs with cryptic merle (also called phantom or ghost merle) typically display little to no merle pattern and some may be misclassified as non-merles. The cryptic merle alleles occur in the lower end of the range (typically from 200-255, however, this range and designation varies by study).
What Is a Harlequin Merle Australian Shepherd? A Harlequin Merle Australian Shepherd carries the merle gene and the co-dominate modifying gene for harlequin. Instead of the normal Merle pattern, Harlequin Merle Australian Shepherds have white patches between each dark patch instead of grey or copper.
Solid black and red coats are the least common coats among Aussie dogs, with solid red being the absolute rarest. The red-colored gene is recessive in dogs, meaning red fur must be present in both parents to make a red-colored pup.