Corneal dystrophy in the German shepherd

The German shepherd is one of our best-loved large dog breeds, and this highly intelligent and very versatile dog from the Kennel Club’s pastoral grouping has a long and distinguished history in a number of important working roles, as well as of course as a loyal and protective pet.

However, German shepherds do have their challenges, particularly when it comes to their hereditary health. Genetic anomalies and conformation defects can cause a range of congenital health problems within the breed, and sadly, some of these have been introduced to the breed population as a result of selective breeding to exaggerate desirable traits.

One of the best known of these is hip dysplasia, and the German shepherd breed’s modern appearance with an acute slope to the back and hind limbs also increases the breed’s risk factors. However, hip dysplasia isn’t the only health condition the breed can be prone to, although it is perhaps the most common serious one – and another hereditary condition that owners or prospective German shepherd owners should be aware of is corneal dystrophy.

This health condition affects the dog’s eyes, and may go on to cause blindness – and it is important to know the symptoms of corneal dystrophy in German shepherds if you share your home with one.

In this article we will talk about corneal dystrophy in the German shepherd in more detail, examining their risk factors, what the condition does, and how to spot the symptoms. Read on to learn more.

What is corneal dystrophy?

Corneal dystrophy is a condition that affects the cornea of the eye – the part of the eye at the front, which covers the iris and pupil. Generally, the condition will affect both of the dog’s eyes at once, but this is not always the case.

Corneal dystrophy comes in two different common variants – epithelial corneal dystrophy and stromal corneal dystrophy respectively. Both types of corneal dystrophy develop due to deposits of calcium or cholesterol building up within the eye, and both conditions are hereditary in nature.

However, their methods of development are slightly different, with stromal corneal dystrophy causing clouding across the cornea, whilst epithelial corneal dystrophy also affects the cells of the eyes, usually leading to the formation of distinctive white spots on the cornea.

There is also a third variant of corneal dystrophy in dogs, called endothelial corneal dystrophy – although this is a degenerative condition rather than a hereditary one, and so the German shepherd dog breed’s chances of developing this variant are no higher than that for any other dog breed.

Why are German shepherds at risk of corneal dystrophy?

Why the German shepherd breed is particularly at risk for hereditary corneal dystrophy isn’t known – the exact gene mutation or anomaly that causes the condition has yet to be identified. However, by understanding the nature of the German shepherd breed and modern breeding practices, it is possible to better understand how health issues and congenital defects can develop within the breed population as a whole.

Pedigree dog breeds are by design limited in terms of their genetic diversity, and the size of the gene pool of unrelated dogs for breeding. To produce a pedigree puppy, their parentage must consist of two dogs of the same breed, and this limitation in terms of genetics increases the risk of hereditary problems being passed on to pups.

A small gene pool of breeding stock increases the risk that gene mutations will be passed on to pups, and that a pup will inherit two copies of a mutation (one from each parent) rather than just one. This in turn raises the risk factors for hereditary health conditions, and specific breeding practices such as breeding closely related dogs or only those with certain desirable physical traits increases the risks.

What are the symptoms of corneal dystrophy in German shepherds?

German shepherds that develop corneal dystrophy tend to do so between the ages of around one and six, and the condition tends to develop slowly over time, which can make it harder for owners of dogs of the breed to identify the subtle changes themselves.

Corneal dystrophy isn’t painful for your dog, but it can obscure their vision, and may ultimately lead to total blindness. It also increases the risk factors for the dog to develop ulcers on the cornea too, which will be painful and that can lead to permanent corneal scarring and associated vision loss.

Can anything be done about corneal dystrophy in the German shepherd?

When it comes to choosing and buying a German shepherd puppy, the breed as a whole is one that the BVA and Kennel Club encourages breeders to have eye screening carried out on prior to breeding, under the remit of the BVA/KC eye scheme.

The eye scheme is a comprehensive test and examination of the dog’s eyes to identify potential problems or risk factors for potential problems, so that breeders can make an informed decision on whether or not to proceed with any given mating match.

Choosing a pup whose parents were tested under the scheme greatly reduces the chances of your own pup coming with hereditary eye problems.

In terms of treating and managing corneal dystrophy in dogs that already have the condition, unfortunately the spots or clouding of the cornea itself cannot be reversed or removed. However, if your dog develops ulcers or secondary complications due to calcium or cholesterol deposits on the cornea, these can be managed and removed to preserve the dog’s vision as far as possible, and to prevent pain or soreness.