Coloboma in Dogs
Coloboma is a congenital condition that causes a hole in the eye’s iris. Coloboma in dogs almost always occurs in Australian Shepherds. Dogs affected by the condition have irregularly shaped irises.
Since coloboma in dogs is a congenital condition, most veterinary researchers believe that it has a genetic source. At this time, though, no one has identified a genetic marker connected to the state. Until a specific gene gets identified, some breeders will unknowingly pass the trait on to offspring.
Symptoms of Coloboma in Dogs
An irregularly shaped iris is the most common symptom of coloboma in dogs. Some dogs, however, experience more problems than others.
A small coloboma may not have any apparent symptoms. Small coloboma in dogs can have minimal effects on the animal’s vision. Many owners never notice coloboma in dogs.
Large coloboma, however, can cause more severe symptoms. For example, a dog’s eyes may not adjust to changes in light. As light becomes brighter, the iris cannot contract to control the amount of light entering the eye. As a result, the dog starts to squint to block painfully bright light.
Diagnosing Coloboma in Dogs
Experienced veterinarians know that they should inspect the eyes of Australian Shepherds. Even a close look, however, may not lead to a diagnosis of coloboma in dogs. A more useful diagnostic tool involves biomicroscopic examinations that can identify small holes in the iris.
Treatment Options for Coloboma in Dogs
Unfortunately, there are no treatment options for coloboma in dogs. Owners can take some precautions, however, to protect their dogs from harm. Dogs with vision problems may wander into unsafe areas, including roads.
Dogs may also find it challenging to live in new environments. When moving to a new home, for instance, it may take the animal several weeks to learn the floorplan and avoid obstacles. Maintaining a clean, clutter-free home can help dogs with coloboma avoid indoor dangers. Leashes are recommended when walking outdoors.
Owners that know their dogs have colobomas should spay or neuter their pets to prevent them from passing the trait on to puppies. Anyone with an Australian Shepherd should have dogs examined before breeding them.