Exercise-Induced Collapse (EIC) in Labradors

A dog that is fetching happily one minute and wobbling the next needs attention. Exercise-induced collapse (EIC) is an inherited condition seen mainly in the Labrador. A dog that seems normal at rest becomes weak and unsteady after intense exercise and excitement [1][2]. Here's the short version. For anything more, see a licensed vet.

What is exercise-induced collapse (EIC)?

• A nervous-system condition. The dog looks completely normal at rest. After intense exercise with high excitement, it develops muscle weakness, loss of coordination and a collapse that can be life-threatening [1][2].
• Caused by one gene. A change in a gene called DNM1 affects how nerves pass signals to each other. The changed gene seems to work less well during intense exercise [1].
• Not painful. A vet school notes that dogs "are not painful or stiff during the collapse or upon recovery" [2].

Is EIC only found in Labradors?

The Labrador is the main breed with a known genetic cause [1]. A vet school also lists the Curly-Coated and Chesapeake Bay Retrievers as main breeds. It names a few others as less often affected, including the Cocker Spaniel and Pembroke Welsh Corgi [2]. A similar condition has been reported in Border Collies, but its gene has not been found yet [1].

Among Labradors tested for the gene change, about 6% were affected and about 40% were carriers [2].

Is EIC genetic or contagious?

It is genetic, not an infection, so it doesn't spread between dogs [1][2].

• A dog shows signs only if it inherits two copies of the gene change, one from each parent [1][2].
• A dog with one copy is a healthy carrier, but it can pass the gene on to its puppies [1][2].

What triggers an episode?

• Intense exercise with high excitement. Field trials, pheasant hunting and repeated retrieving are common triggers. Routine jogging rarely causes an episode [2].
• A high-drive dog. Excitable, high-energy dogs are the most likely to be affected [2].
• Warm weather. Heat makes an episode more likely, though it can happen in any season [2]. In the Saudi summer, ask your vet how to plan play around the heat.

At what age do signs start?

Usually between about 5 months and 3 years, with an average of around 14 months. More than 80% of affected dogs show their first signs by age 4 [2].

When should I see a vet?

Stop all exercise at once and see a licensed vet if your dog:

• Becomes weak or wobbly in the back legs during or after intense exercise or excitement [2].
• Moves with a "wide-based, long, loose stride", not the short steps of simple tiredness [2].
• Keeps trying to move while its back legs give way or drag [1][2].

Important: collapse after exercise can have several causes, and in rare cases a severe EIC episode can be fatal [1][2]. A vet needs to check what is happening. After any episode, see your vet before your dog returns to hard exercise [2].

In hot weather, also learn the signs in our heatstroke article.

Can EIC be prevented?

There's no guarantee, but a DNA test helps breeders and buyers make informed choices:

• The DNA test shows whether a dog is clear, a carrier or affected. It is used to guide breeding decisions [1][2].
• Ask the breeder for the parents' EIC test results, especially for working or field-line puppies [1][2].
• Healthy parents matter. The breed standard says only "functionally and clinically healthy dogs" should be bred [3].
• For a dog known to be affected, ask a licensed vet to set an exercise plan suited to your dog and the Saudi climate [2].

FAQ

Is exercise-induced collapse painful?

No. Dogs are described as not painful or stiff during an episode or afterwards [2]. Still, see a vet after any collapse.

Can a carrier dog have episodes?

No. A carrier has one copy of the gene change and stays healthy. Only dogs with two copies are affected [1][2].

Does normal jogging trigger EIC?

Rarely. Episodes are usually linked to intense, exciting activity such as field trials or repeated retrieving [2].