They are not the ice blue of the puppy above, whose eyes will remain blue. Pups with eyes destined to be fairly light, such as amber, would have irises a lighter shade of gray than these. On the left, Frank is 7 weeks old and his eye clearly shows a difference in pigment color. At this point the dark quarter is just an indistinct smudge of darker brownish gray on a greenish blue field. On the right Frank is an adult with a distinct quarter split.
When a dog's iris contains two or more colors, the medical term is heterochromia iridis. Common terms for multicolored irises are split eyes and marbled eyes.
Common terms for two eyes different from each other include odd eyed, walleyed, glass eyed. In domestic mammals having one pigmented eye and one blue eye is not uncommon. It's been observed in horses, donkeys, cattle, water buffalo, cats, ranched foxes, and dogs. This blue merle Aussie belonging to Melanie Magamoll has a sky blue field with an indigo ring around her pupil. She also has deep blue flecks in the lower left of the indigo ring. It is not known at this time why some Aussies inherit the indigo ring while others' blue eyes are uniform blue.
There are probably several genes involved. Jackson's eye shows dark amber with blue marbling. The light blue area has some fascinating heavy blue striations near the pupil.
His right eye is amber with similar looking striations of darker amber. Jackson is a red merle. Not all flecks are blue. Chaps has a blue spot in the brown half of his iris and a brown spot in the blue half! Chaps is a grandson of Krackers, a Slyrock dam. This is the eye of Scrappy, a blue merle. Scrappy has the sky blue field, the indigo ring, and some very dark brown marbling in the upper left corner of his eye. He has a partial mascara line on the right side of his lower eye. Pigment on the eyerim is highly desireable for preventing sunburn and skin cancer.
The pink half is much more prone to sunburn than the black half. Hazel has blue marbling on her light brown eye. Sometimes a dog has two marbled eyes, and sometimes one is marbled while the other is not.
This eye resembles a geometric split, but notice that the edges where blue meets brown are soft edged rather than sharp. This rather striking eye belongs to Bonzer, a blue merle. His genetic eye color is dark brown, but the effect of the merling is to remove pigment from most of the iris. This gives him the very striking dark brown areas on a bright blue field. This is a very impressive marbled eye! Zeke has some very interesting and attractive marbling. His base eye color is dark amber, but the iris is encircled by a darker brown ring.
The eye is marbled in blue left corner and by a grayish color bottom center. Here the distinction between blue and dark amber is a very soft blending without sharp distinctions. Blue, pictured in the blue merle section, has dark amber eyes. In both eyes he has a darker amber ring around the iris and several brown flecks in the iris.
Vicky was a homozygous merle with blue eyes. Notice that a large piece of iris on the right side of the pupil is missing. This incomplete development of the iris is called iris hypoplasia. It is not uncommon in homozygous merles, though it can occur in other dogs also. Vicky had missing pieces of iris in both eyes. She also had a coloboma at about the 1 o'clock position in her iris.
She tended to squint in bright light since her irises could not close down adequately to block out the excess light. She was able to navigate the furniture and toys in the yard without difficulty! This is Fanfare, a lovely black bi with bright yellow eyes. Bold yellow irises like these are most often found on reds. They are definitely attention grabbing on a black dog. Research shows that livestock are quicker to retreat from the predatory threat of a dark colored dog with light eyes than to dogs with brown irises that don't stand out from the coat as much.
This is Mina, photo courtesy of Danette Brake. Her eyes have an arresting quality! They are just a shade darker than yellow and would be classified as light amber. Amber ranges in tone from very light eyes like Mina's through all shades of hazel. This is Willow, photo courtesy of Judy Rolff. She is a red tri with greenish amber eyes!
Green eyes are most often seen in reds and red merles, much more rarely in blacks or blues. Dogs, cats, horses and people can have heterochromia. This condition is caused from a lack or excess of melanin a pigment found in hair, eyes and nails.
The term for too much melanin is hyperchromic. Acquired heterochromia happens due to inflammation, injury and some brain tumors that may alter the iris color. In general, Australian shepherds have bushy, bobbed tails. Check out the tail and head are at the same level when both keep upwards. In fact, Check its tail as he holds it upright. If you can see an arc shape upwards, that Aussie can be a purebred one. Melanin determines several aspects of our appearance.
And while we have the least amount when we enter the world for the first time, remember that babies may be born with eyes of blue, brown, hazel, green, or some other color. What causes heterochromia? The most common cause of heterochromia is a genetic mutation that results in an individual born with two differently colored eyes.
This mutation is not usually harmful and, as mentioned, usually does not influence the quality of vision. Given what we know then, when do puppies eye change color from blue to something else? After puppies have opened their eyes, they will be blue in color. It takes several weeks for their eyesight to fully mature and become sharp, and then the color to change. Before this occurs, they will lack the same range of vision as an adult dog and will occasionally bump into or stumble over items around the home.
Likewise, similar to their vision, it will take them several weeks to start developing melanin in their eyes — this melanin is directly responsible for the eye color they will develop, with larger amounts of melanin giving them darker eyes, and smaller amounts giving them lighter. In fact, it could take up to 3 to 4 weeks before their eyes have fully developed into the permanent color they will have as adult dogs instead of the blue they are born with.
The reason why puppies have blue eyes when they are born is quite simple, it comes down to a lack of melanin in their irises, which only begins to develop as they get older. Due to this absence of melanin, their eyes appear to look bluish, however, they are more of a clear color. To further expand on this, the blue appearance in their irises is caused by the lack of melanin coupled with the refraction and reflection of light.
If you are the owner of a litter of newborn puppies, you will probably have noticed that their eyes will not have opened yet. In fact, for the first 8 to 14 days they will remain tightly closed. During this time, they will effectively be blind and will use their paws and nose to feel around their environment, usually whilst on the lookout for mom.
Blind dogs can lead very happy lives. Also, they will climb over or under their siblings to get to wherever they want to be, which can be a cute thing to observe. More often than not, they will be a foggy shade of blue. However, some puppies will be born with eyes that are slightly greyer or a different shade of blue.
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