Regular twice-yearly wellness exams give your vet the opportunity to check your dog's eyes for signs of developing cataracts and recommend treatment before they become more serious. When it comes to saving your dog's vision, early diagnosis of conditions such as cataracts is important. Cataract surgery might not be an option for your dog if he already has a retinal detachment, retinal degeneration, glaucoma, or severe eye inflammation. However, not all canines with cataracts are good candidates for this procedure. It is frequently possible to surgically remove canine cataracts and replace them with artificial lenses. A cataract is an opacification or cloudiness that can occur on all or part of the lens, interfering with the focus of a clear image on the retina and limiting your dog's ability to see clearly. This lens focuses your dog's vision to provide clear vision. No male that is a CEA carrier should be used extensively at stud.Each of your dog's eyes has a lens similar to that of a camera. Give preference to clear-tested offspring to carry on with. Do not breed affected dogs and breed carriers only to clear-tested mates. With the DNA test CEA can easily be managed in your breeding program without fear of producing more affected pups. What does CEA mean for my breeding program? Given that about one in 10 Aussies is a carrier it would be a good idea to test all breeding dogs for CEA unless bothh of its parents have tested clear. If your dog does not have the mutation it is clear of CEA. Dogs with one copy of the mutation are carriers. Dogs with two copies are affected, whether or not they have clear eye exams (see the question about masked affecteds, above). Results will indicate whether your dog has one, two, or no copies of the mutated version of the CEA-CH gene. It tests for the gene mutation that causes choroidal hypoplasia which is present in all CEA dogs. How likely is it that a normal littermate to a puppy with CEA carries the gene?Įvery normal full sibling of a dog with CEA has a 2 in 3 chance of being a carrier. It is likely that somewhere about 10% are carriers. Since all dogs with CEA have CH it can be managed in the same way one would manage any single gene recessive trait even though other as-yet unidentified genes cause the more serious defects.Īround 1% are affected. Yes, the gene which causes choroidal hypoplasia has been located and the mutation is recessive. The senses of smell and hearing are more important to a dog than vision and most dogs adjust well, particularly those blind from birth as would be the case if the dog had CEA. If a dog is totally blind it can live a good life though certain activities won’t be possible and it will need to be protected from hazards it cannot see. Dogs that are blind in one eye can function well but can be at risk from hazards that arise on their blind side activities like agility and stockwork may be ill advised. Optic nerve coloboma can reduce vision and very large colobomas can leave the dog blind in the affected eye. Most dogs with CEA have only choroidal hypoplasia and their vision is functional. The pigment is not present in young puppies but starts to fill in at about 6 weeks.ĬEA causes no pain or discomfort, but it can impact vision. If a dog has only choroidal hypoplasia sometimes the natural pigment in the back of the eye hides its presence. These dogs do have the disease they just can’t be diagnosed by eye exam. A puppy eye exam can also detect other congenital and inherited eye defects for which we do not have DNA tests.Ī dog that has CEA that can’t be detected in an eye exam is a masked affected. Ideally, puppy exams should be done before 6 weeks of age to be sure they are checked before any might become masked affecteds. If a puppy is a double merle you won’t know because the eye defects typical in dogs that inherit two copies of the merle gene will make it impossible to recognize CEA for what it is. If they aren’t checked young, they may become masked affecteds (once referred to as “go normals”) and be indistinguishable from unaffected dogs. If you don’t check all the puppies in every litter, you may miss the affected ones. But if that is not the case an early puppy eye screen is vital. If at least one parent has CEA tested clear it isn’t necessary. Why do you have to check all puppies producd and check them at a young age? In most cases you won’t know without an exam by a veterinary ophthalmologist, thoughoccasionally a puppy will be blind. Another less common CEA defect is retinal detachment. Some dogs also have optic nerve coloboma, in which a portion of the optic nerve where it enters the back of the eyeball has failed to develop. The most common defect is choroidal hypoplasia (CH), also called chorioretinal dysplasia, a thinning of the vascular tissue that lies between the retina and the wall of the eyeball. CEA is a disease of the vascular and nerve tissues in the back of the eye.
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