Exercise-induced collapse

Exercise-induced collapse (EIC) is a genetic syndrome, predominantly occurring in mixed breed dogs related to several retriever breeds as well as purebred Labrador Retrievers but also seen in Chesapeake Bay Retrievers and Curly Coated Retrievers, Boykin spaniels, Cocker spaniels, German wire-haired pointers, Old English Sheepdogs, Bouvier des Flanders, Pembroke Welsh corgis and Clumber Spaniels (Verified 2015 by Laboklin in the UK).

The syndrome was first positively identified by DNA in Boykin Spaniels in 2010. Before this, EIC episodes may have been misdiagnosed as heat stroke.

Affected dogs show signs of muscle weakness, loss of coordination, severe marked increase in body temperature and life-threatening collapse when participating in strenuous exercise or activity. Affected dogs can tolerate mild to moderate exercise, but just 5 to 20 minutes of strenuous activity, or even extreme excitement such as that seen in field trials or hunt tests, can induce weakness or collapse. Dogs affected with EIC usually cannot continue with intense retriever training, but can live normal lives as house pets. A few affected dogs have died during exercise or while resting immediately after an episode of exercise-induced collapse so an affected dog's exercise should be stopped at the first hint of incoordination or wobbliness.

EIC is being observed with increasing frequency, either from the genetics becoming more widespread or from previously misdiagnosed cases being correctly identified now that there is evidence in the form of a DNA test. Dogs that have EIC are prone to mild to severe collapse that can range from dragging of the hind legs to complete collapse. Most affected dogs have been from field-trial breedings. Signs become apparent in young dogs as they enter heavy training, which is usually between 5 months and 7 years of age as stated in the initial UMN study in 2007.^[1] Dogs of either sex can be affected. Dogs with this condition are always normal at rest and are usually described as being extremely fit, prime athletic specimens of their breed.

Nervous system, cardiovascular and musculoskeletal examinations are unremarkable as is routine blood analysis at rest and during an episode of collapse.^[2]

Through grants from the AKC CHF a patented DNA test was developed by the University of MN.^[3] The Orthopedic Foundation for Animals provides a public database for those dogs that are DNA tested.

The UMN VBS Genetics Lab is also investigating cases of "atypical collapse"^[4] and also "Border Collie Collapse]"^[5] where the dog is a carrier or clear of the disease on the DNA test, but continues to exhibit signs of the EIC disease.

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