Pannus is a disorder that affects the eye of the greyhound which can eventually lead to blindness if not managed.

It is not painful in its early stages, causes no discharge from the eye, and may be hard to see unless you look closely at your greyhound’s eyes in good light.

If it is not diagnosed or treated, the disease can slowly cover the clear part of the eye (the ‘cornea’) until the dog can no longer see.

The disease has a genetic component, within certain families and lines within a breed more likely to be affected, but environmental and other factors also play a part in the development of the disease. Pannus is a concern in greyhounds, not only because it can cause loss of sight, but also because some treatments for the disease may result in a positive swab if adequate withdrawal times are not adhered to.

Furthermore, GAR Rule 74(3) prohibits any greyhound from competing in an event if an officiating veterinarian reasonably suspects the greyhound to be suffering impaired vision in one or both eyes. This makes pannus a very serious and potentially career-limiting disease for racing greyhounds.

QRIC is working with the greyhound racing industry to try to limit the incidence of the disease in racing greyhounds. This can be achieved with the help of industry participants.

If a greyhound has been diagnosed with pannus, serious consideration should be given to excluding it from breeding to ensure that it does not pass the condition onto the next generation of greyhounds. In this way, the incidence of pannus in the greyhound industry can be significantly reduced over time.

WHAT DOES IT LOOK LIKE?

Pannus symptoms generally start to appear when the dog reaches 2-5 years of age. In the beginning you may notice that only the edge of the cornea seems more pigmented (coloured) than before – like ‘freckles’ developing near the edge of the eye – or there may be a hazy/greyish colour to the edge of the clear part of the eye.

Generally, the disease will occur in both eyes, but may be of differing severity. As the disease progresses, pannus lesions may appear as brown pigment ‘growing’ onto the surface of the eye, or as ‘greyish-pink’ areas of inflamed tissue, which eventually turns into scar tissue.

These lesions can eventually spread inwards until the entire eye surface is covered, leaving no clear window for light to enter the eye – making the dog blind.

If you notice any changes in your dog’s eyes it is important to have them checked by a vet. Other diseases and conditions of the eye can look very similar, particularly in the early stages, and the treatment required may be very different.

WHAT CAUSES IT?

Pannus is thought to be an auto-immune disease; these are diseases where the body’s immune system starts to attack the body. Exposure to Ultra-Violet (UV) light is another important factor thought to contribute to pannus. Such exposure to UV light is thought to trigger the start of the condition, or to make the condition worse. Hence, it is important to keep affected dogs out of bright sunlight, especially in the summer months, as the rate of progression of pannus increases with exposure to UV light (from sunlight, or reflected light from water).

CAN IT BE TREATED?

Once the disease has started, there is no ‘cure’ that eliminates pannus. All treatments are directed at slowing the progression of the disease and to prevent flare-ups.

The most used treatment is cortisone eye drops. The cortisone limits the body’s immune response, which slows the progression of the disease.

Other treatments including cyclosporine drops may also be used. All corticosteroids (cortisones) are considered ‘prohibited substances’ under the Rules of Racing if detected on race day. Therefore, medication must be stopped in sufficient time prior to the racing engagement, to ensure the drug is completely out of the dog’s system on race day. In some dogs this may result in a flare-up of the condition and such dogs may need to be managed differently or retired from racing.

WHAT SHOULD I DO IF I SUSPECT ONE OF MY GREYHOUNDS MAY BE AFFECTED BY PANNUS?

The first thing to do is to consult your greyhound veterinarian. They will be able to examine the eye, confirm the diagnosis and discuss treatment options with you. Early diagnosis increases the chance of successful control of the condition. So don’t hesitate – take the greyhound to your vet for a check-up.