Collie eye anomaly

Collie eye anomaly (CEA) is an inherited abnormality in the development of the retina. It is known to affect Rough and Smooth Collies, Shetland Sheepdogs, Lancashire Heelers, and several other breeds. It is bilateral, affecting both eyes, although to varying degrees. In the mildest form vision is not impaired, but it will lead to blindness in the most severe form. The mode of transmission is that of a simple recessive gene, so a dog may be a carrier without showing any clinical signs of the disease. Pups should be tested at seven weeks of age to determine if they are affected by this disorder, but it should be noted that the test does not identify carriers. As the eye matures the normal pigmentation can mask the symptoms of CEA, so the test before the age of 8 - 10 weeks is critical.

There is now a DNA test available for CEA

Many conscientious breeders are taking advantage of the newly developed DNA test to determine carriers as well as those affected by CEA. Prospective owners should inquire about the test results of both parents. If both sire and dam are clear, the pup will be neither affected nor a carrier of CEA. A positive result for one or both parents should be followed by a DNA test for the offspring as well.