As the name suggests, dogs with Exercise Induced Collapse (EIC) may collapse after several minutes of strenuous exercise.
It is found mainly in Labrador, Chesapeake Bay and Curly Coated Retrievers, and Boykin Spaniels. Similar genes occur in other breeds - Cocker spaniels, German wire-haired pointers, Old English Sheepdogs, Bouvier des Flandres, Pembroke Welsh Corgis and Clumber Spaniels.
Originally the disease seemed to be limited to field-bred Labradors, however, it is also in conformation, service and pet bloodlines. It can affect both males and females and, in Labs, all three colors.
It can also occur in mixed breeds, such as doodles and dilutes, that have genetics from one of the affected breeds.
Collapsing due to EIC is most often seen in excitable, very fit dogs with lots of drive. It usually only takes a few minutes of strenuous exercise to cause a collapse which starts in the rear legs - wobbling and often crossing before they stop working. The dog will try to continue running with its front legs while dragging the rear legs.
Some dogs have died while exercising or while resting immediately after an EIC episode. Therefore it's important to stop all exercise and cool the dog down at the first sign of an episode.
Other EIC affected dogs have never experienced a collapse. This might be because they are not an excitable dog or don't participate in strenuous activities.
Here is a video from the University of Minnesota where they are researching EIC.
Symptoms may not be triggered until young dogs - about seven months to two years - start heavy training.
Common triggers, especially when combined:
- excessive excitability
- strenuous exercise such as repetitive retrieving, intense play, upland bird hunting, long-distance running
- higher temperatures and humidity than the dog is used to
Often the first signs are a rocking gait, followed by weakness in the back legs, sometimes to the point of dragging their legs. Dogs may stand with their feet further apart or pick them up higher than normal.
As the collapse progresses, the dog may drag their back legs while running with the front legs. Or they might fall over while trying to run.
Most dogs are alert, but may seem confused. Some dogs may still try to run and their front legs might be stiff. Or they may not be able to move their head and legs. They don't seem to be in pain. Body temperature is often high.
Symptoms may worsen for a few minutes, but after 10-20 minutes the dog should start returning to normal. It may take longer for their body temperature to return to normal.
In extreme cases, there could be seizures and even death.
Researchers found a gene that appears to be the main cause of EIC. If a dog has two copies of the affected gene, it is at risk of collapsing. These dogs are called 'affected.' If a dog has two copies of the normal gene, they are not at risk of collapsing due to EIC. They are called 'clear.' If a dog has one copy of the affected gene and one copy of the normal gene, they are called 'carriers.'
A carrier is not at risk of collapsing due to EIC, however, they may pass the affected gene to their puppies. Therefore it's important to never breed a carrier with an affected or to another carrier. Doing so will likely produce some affected puppies.
However this may not be the entire story. There are some dogs with two copies of the affected gene that have never collapsed. Some dogs may be just more laid back and don't reach the level of excitement to trigger a collapse.
Or there may be another gene that modifies the affected gene. If such a gene exists, it may cause some dogs to collapse more often than other dogs. Or it may help protect some dogs from collapsing at all.
Or there may be something in how the dog is fed, exercised, or trained that changes their susceptibility.
A genetic test is available to identify the gene that causes exercise induced collapse.
Because EIC is caused by a recessive gene, both of a dog's parents must carry at least one copy of the gene for a dog to be affected. About 30% of tested Labradors carry the gene.
If you're buying a puppy or dog, make sure at least one parent is clear of EIC. Or you can have the puppy itself tested. The test is simple - just three swabs between the cheek and gum. Make sure the dog hasn't eaten anything for at least an hour. Wash your hands and keep the dog separated from other dogs until you've finished swabbing - twice on one side and once on the other side. Place the swabs back into the packaging and into an envelope to send to the lab. There are more extensive directions and a link to the lab I use on the CNM page.
Provided one parent is clear, the worst the puppy can be is a carrier (one copy of the gene). Carriers won't suffer EIC collapses, make fine pets and even competition dogs. However if they are bred, it should only be to a dog that has been tested clear of EIC.
Many top competition dogs carry one copy of the EIC gene, so don't let that stop you from choosing the best dog for you.
Better conditioning and avoiding strenuous exercise during warmer weather may help prevent collapsing. Many affected dogs can tolerate mild to moderate exercise. The high-energy, excitable dogs may need to be removed from training.
The best treatment for most dogs affected by EIC is avoiding known trigger activities, especially when they are combined with extreme excitement and warmer-than-normal weather.
Most dogs that are retired from activities that trigger collapsing can live out their lives without problems. However, it's still a good idea to be aware and stop all of the dog's activity at the first sign of weakness. If the dog seems overheated, you can also lightly spray it with cool water to bring down its temperature.
Keep your veterinarian informed if your dog does have an episode. She may want to do some tests to confirm your dog is otherwise fine.
OTHER PROBLEMS WITH SIMILAR SYMPTOMS
Overheating (this can be an emergency)
- frantic panting, increased heart rate, extreme drooling, labored breathing, bright red membranes
- may be dizzy and appear confused
- may collapse and/or experience seizures
- may vomit and/or have diarrhea
CNM (learn more)
- gait abnormalities
- generalized weakness
- tires easily
- muscle wasting
- symptoms usually develop as a puppy (2-5 months old)
- once the symptoms develop they are almost constant