Progressive Retinal Atrophy (PRA) in Dogs
Ever wondered how your dog’s eyes work? It’s all about the retina which is like the film in a camera, sitting at the back of the eye. Its job? To catch light and turn it into signals the brain can understand.
The retina is packed with cells called photoreceptors. There are two types: rods and cones. Rods are night vision champs and help spot movement. Cones handle daytime and colour vision. Dogs have loads more rods than cones, which is why they’re ace at seeing in low light.
But that’s not all. The retina also has a special layer called the tapetum lucidum. It’s like a built-in torch that reflects light back through the retina. That’s why dogs’ eyes shine in the dark. Pretty cool, right?
What is Progressive Retinal Atrophy (PRA)?
PRA isn’t just one disease, but a group of eye problems that make dogs go blind over time. It messes with those photoreceptor cells we talked about earlier.
PRA makes these cells die off slowly. It usually starts with the rods, so night vision goes first. Then it hits the cones, and daytime vision fades too.
The tricky bit? PRA doesn’t hurt. Dogs often adapt so well that owners don’t notice until the disease is pretty far along.
It’s genetic, passed down from parent dogs to their pups. That means some breeds are more likely to get it than others. And once a dog has it, there’s no way to stop it. But don’t worry, we’ll chat about how to help your furry mate cope.
Are There Different Forms of Progressive Retinal Atrophy?
You bet there are. Progressive Retinal Atrophy isn’t a one-size-fits-all problem. Different types kick in at different ages. First up, we’ve got early-onset PRA. It’s also called retinal dysplasia. This type shows up in puppies. Their retinas never develop right from the start. It’s rough because these pups can be blind by the time they’re one or two years old.
Then there’s late-onset Progressive Retinal Atrophy. This is more common. Dogs are born with normal eyes, but the retina starts to break down as they get older. It can start anywhere from 3 to 9 years old. Other eye problems can look like PRA too. Achromatopsia makes dogs lose daytime vision first. And SARD? That’s when a dog goes blind fast, in days or weeks.
How Does It Happen?
Progressive Retinal Atrophy is all about dodgy genes. It’s inherited, which means it’s passed down from parent dogs to their pups. Most of the time, it’s what we call autosomal recessive. That means a dog needs to get the faulty gene from both mum and dad to get PRA. It’s like a genetic double whammy.
But in some breeds, like Old English Mastiffs, it’s dominant. So a dog only needs to get the gene from one parent to be at risk. And in a few breeds, like Siberian Huskies, it’s linked to sex. Males are more likely to get it than females.
No matter how it’s inherited, PRA makes the light-catching cells in the retina die off over time. First, the rods go, then the cones, until the dog can’t see at all. It’s like someone’s slowly turning off the lights.
Are Any Dog Breeds More Likely To Get Progressive Retinal Atrophy?
Absolutely. Some breeds hit the genetic jackpot (or should I say, lose the genetic lottery?) more often when it comes to PRA. Poodles, especially the miniature ones, are high on the list. So are Labrador Retrievers and Golden Retrievers. If you’ve got an English or American Cocker Spaniel, keep an eye out (pun intended).
Mini Goldendoodles, Australian Cattle Dogs, Tibetan Terriers, Spaniels, Basenjis, and Cardigan Welsh Corgis are also at higher risk. So are Papillons, Irish Setters, and Shetland Sheepdogs. But here’s the kicker: even if your dog’s a mixed breed, they’re not in the clear. PRA can show up in any dog, purebred or not. It’s just that some breeds are more likely to have the faulty genes.
What Are The Signs of Progressive Retinal Atrophy (PRA) in Dogs?
Spotting PRA can be tricky because it comes on slowly. But there are signs to watch for. First off, night blindness. Your dog might not want to go out after dark or get jumpy in dim light. They might bump into things more when the lights are low.
As it gets worse, you’ll notice problems during the day too. Their pupils might look bigger than normal, trying to let in more light. And their eyes might have a weird shine to them in the dark.
Watch for changes in how they act. They might not want to go into dark rooms or downstairs. They might start bumping into things more, even in places they know well.
Also Read: Health Screenings in Mini Goldendoodle Before Breeding
The tricky bit is that dogs are good at hiding problems. They learn their home layout and use their other senses to get by. So by the time you notice something’s off, PRA might be pretty far along.
How does PRA affect my dog?
PRA changes how your dog sees the world, but it doesn’t have to change their whole life. As PRA progresses, your dog’s vision will get worse. First, they’ll struggle to see in low light. Then daytime vision will start to go too. Eventually, they’ll lose all sight.
Dogs are amazing at adapting. They’ll start using their other senses more. Their hearing and sense of smell will become their new eyes. Progressive Retinal Atrophy in Dogs doesn’t cause pain, which is a small mercy. And it doesn’t affect your dog’s lifespan or overall health. With some changes at home and lots of love, blind dogs can live happy, full lives.
Your job? Help them adapt. Keep things in the same place at home. Use your voice to guide them. And most importantly, keep treating them like the awesome dog they are.
How Fast Does PRA Develop?
PRA isn’t a sprint, it’s more of a marathon. The speed can vary a lot depending on the type of PRA and the individual dog. In early-onset PRA, things move fast. Puppies can start losing vision by 2-3 months old and might be blind by 1-2 years.
Late-onset PRA is slower. It usually starts in adult dogs, anywhere from 3 to 9 years old. From there, it can take months to years for a dog to go completely blind. Some dogs lose vision gradually over several years. Others might go blind more quickly, in a matter of months.
The key thing to remember? PRA always leads to blindness eventually. But because it’s usually slow, most dogs have time to adapt. They learn to use their other senses and can still have a great quality of life.
How Is Progressive Retinal Atrophy (PRA) in Dogs Diagnosed?
If you think your dog might have PRA, it’s vet time. They’ll do a few checks to figure out what’s going on. First, they’ll look at your dog’s eyes with a special torch called an ophthalmoscope. They’ll check how the pupils react to light and look at the back of the eye (that’s the fundus).
If they suspect PRA, they might send you to a dog eye specialist (yep, that’s a thing). These vets have fancy kits like an electroretinogram (ERG) that can spot PRA early on. There are also genetic tests for some types of PRA. But here’s the catch: we don’t know all the genes that cause it yet. So a dog could test negative and still develop PRA later.
The tricky bit is that cataracts can develop in the late stages of PRA. If they’re bad enough, they can make it hard to see the retina. That’s why early diagnosis is so important.
Could My Dog’s Signs Be Caused By Something Else?
Progressive Retinal Atrophy isn’t the only thing that can make a dog go blind. Other eye problems can cause similar signs. Cataracts are a big one. They make the lens cloudy and can look a bit like PRA. Glaucoma’s another possibility – that’s when pressure builds up in the eye.
Uveitis, which is inflammation inside the eye, can cause vision loss too. So can lens luxation, where the lens slips out of place. And don’t forget about problems with the optic nerve. That’s the cable that sends signals from the eye to the brain.
Also Read: Dog Ear Infections – Causes, Symptoms, and Treatment
The key difference? Most of these other problems hurt. PRA doesn’t. So if your dog’s eyes look sore, it might not be Progressive Retinal Atrophy in Dogs.
That’s why it’s so important to get your vet to check things out. They can figure out what’s going on and help you make a plan.