Cataracts
Any opacity of the eye lens is called a cataract. There are many causes of cataracts and some of these are inherited. If the cataracts are in both eyes and they mature the dog may become blind. Surgery is available in the cases where the cataract grows and causes vision loss.
The posterior, polar, subcapsular cataract (PPS) is better known as the star cataract. It is usually in both eyes and becomes apparent between 6 to 18 months of age. Some dogs develop this problem as late as 6 to 7 years of age or in some cases as early as 6 to 8 weeks. This cataract may be slowly progressive but it rarely interferes with vision. The condition is inherited, probably as a dominant trait with incomplete penetrance. It is advised not to breed from affected animals as matings with affected dogs have produced litters of blind pups. The condition is inherited, probably as a dominant trait with incomplete penetrance.
Entropion
Entropion is an inherited condition of the eyelid where the border of the eyelid turns in and hair normally on the outside of the lid rubs on the surface of the eye causing irritation and in severe cases ulceration of the cornea. Surgery is required to alleviate the dog’s discomfort and prevent damage to the eye. There are a number of genes are involved in the inheritance of entropion. Other factors such as head conformation, eye socket shape and depth are involved. Affected animals should not be used in a breeding program.
Extra Eyelashes (Distichia)
Extra eyelashes are found right on the eyelid edge, and they grow from glands in the eyelid edge. They are also called distichia - as they form a double row of eyelashes. Extra eyelashes may or may not cause irritation to the eye. Most Golden Retrievers affected do not have clinical signs or evidence of corneal irritation. Surgery is only required if the extra eyelashes are actually causing disease. The condition is believed to be inherited in a dominant manner.
Progressive Retinal Atrophy (PRA)
Progressive Retinal Atrophy (PRA) is an inherited, genetic disease that causes vision loss. The retina is the light sensitive layer of tissue at the back of the eye and is responsible for registering visual stimuli and transmitting them through the optic nerve of the brain. In retinal atrophy, this layer of tissue gradually degenerates. Affected dogs have night blindness, progressing to day blindness. Most cases of PRA end up developing cataracts. PRA is inherited as an autosomal recessive trait. This means that the condition is passed on from both parents. This condition is rare in the Golden Retriever in Australia.
Persistent Pupillary Membranes (PPMs)
Persistent Pupillary Membranes (PPMs) are strands of tissue that fill the front, fluid chamber of the eye. These tissues should have dissolved away as the eye developed. Instead they persist and can affect vision in the more severe cases. Most cases of PPMs are mild but may result in small focal cloudy spots in the front of the eye.
Dogs used for breeding should be issued with an ACES (Australian Canine Eye Scheme) certificate from a veterinary ophthalmologist. These certificates are required to be renewed annually.
