Eye disease is common in the dog. It takes many different forms and can affect any part of the eye, a very specialised and complicated organ both anatomically and embryologically.
Eye diseases may be inherited and both congenital and non-congenital conditions occur. However, eye disease may also be due to infectious agents, such as bacteria, viruses and fungi, deficiency of certain substances, toxins or injury.
Inherited eye diseases are both important and
common in the dog, as they are in humans, and may show remarkable similarities
in the two species, examples being cataract and retinal degeneration.
Which eye diseases are inherited?
Inherited eye disease is divided into congenital
conditions, ie those present at birth and non-congenital eye conditions,
ie those which arise later in life. Not all congenital eye conditions are
inherited.
Congenital eye diseases
Collie eye anomaly - affects only the collie breeds (Rough Collie, Smooth Collie, Shetland Sheepdog and also Border Collie).
Retinal dysplasia - total and multi focal, affecting breeds such as Labrador Retriever, Sealyham Terrier, Cavalier King Charles Spaniel, English Springer Spaniel and American Cocker Spaniel.
Congenital hereditary cataract - Miniature Schnauzer.
Persistent hyperplastic primary vitreous - Doberman and Staffordshire Bull Terrier.
Persistent pupillary membrane - Basenji.
Goniodysgenesis - may lead to glaucoma in the
Basset Hound, Flat-coated Retriever, Siberian Husky, American Cocker, Cocker
and Welsh Springer Spaniels.
Non-congenital inherited conditions
Generalised progressive retinal atrophy - Rough Collie, Miniature Long-haired Dachshund, Elkhound, Irish Setter, Miniature Schnauzer, Miniature and Toy Poodle, Chesapeake Bay and Labrador Retrievers, American Cocker and English Springer Spaniels, Tibetan Spaniel and Terrier and Cardigan Welsh Corgi.
Central progressive retinal atrophy - Border Collie, Briard, Rough and Smooth Collies, Golden and Labrador Retrievers, Shetland Sheepdog, Cocker and English Springer Spaniels and Cardigan Welsh Corgi.
Hereditary cataract - Belgian Shepherd, Boston Terrier two forms), Cavalier King Charles Spaniel (two forms), German Shepherd Dog, Irish Red and White Setter, Large Munsterlander, Miniature Schnauzer, Norwegian Buhund, Old English Sheepdog, Standard Poodle, Chesapeake Bay, Golden and Labrador Retrievers, Siberian Husky, American Cocker and Welsh Springer Spaniels, Staffordshire Bull Terrier.
Primary lens luxation - Border Collie, Miniature
Bull, Smooth-haired and Wire-haired Fox, Parson Jack Russell and Sealyham
Terriers.
What is being done to control hereditary eye disease?
The British Veterinary Association/Kennel Club/International Sheep Dog Society Eye Scheme recognises, and certifies, 11 different hereditary eye diseases in 47 breeds and these are known as Schedule 1 conditions. Some breeds have as many as four separate hereditary eye diseases; some have none.
Another 12 eye diseases are under investigation as of possible hereditary origin, these are mainly the same hereditary conditions already recognised as Schedule 1 diseases, but in different breeds.
Whenever a condition which is under investigation becomes a proven hereditary eye disease it is transferred into a Schedule 1 disease.
All dogs participating in the scheme are examined
by a qualified veterinary ophthalmologist (ie a veterinary surgeon who
specialises in eye disease and is recognised as such a specialists by the
British Veterinary Association and the Kennel Club).
How can I participate in the Eye Scheme?
The scheme depends on owners and breeders presenting
their animal to a member of the official panel. The certificate carries
the official registered name and number of the dog, its breed, colour,
sex and date of birth as well as the owner and veterinary surgeon’s names
and addresses. The dog is examined with an ophthalmoscope and slit-lamp
biomicroscope (an instrument particularly suitable for examination of the
lens for cataract), following dilation of the pupil. In certain breeds
affected with glaucoma a goniolens is also used to examine the angle of
filtration. This examination only reveals affected animals and not ‘carriers’
of inherited conditions. Individual certificates are issued for dogs of
any age and owners are advised that the dog should be examined at least
every 12 months and certainly during its breeding lifetime.
Does the Scheme work?
There is no doubt that the BVA/KC/ISDS eye scheme
has been instrumental in reducing the incidence of certain hereditary eye
diseases in some breeds and in educating dog owners, breeders and the veterinary
profession on hereditary eye disease. However, success depends upon the
continued presentation of dogs to the scheme and full co-operation between
owners and their vets. All dogs used for breeding, even if there is no
currently recognised inherited eye abnormality in that breed, should be
examined under this scheme prior to breeding. Puppies should only
be purchased from reputable breeders with stock certified from hereditary
eye diseases.