Some Labrador retrievers are collapsing from a syndrome called exercise induced collapse. After 5 to 15 minutes of strenuous exercise, affected Labrador retrievers develop weakness, incoordination and can collapse.

The syndrome is being increasingly observed in young adult Labrador retrievers of both sexes and any color, primarily from field-trial breedings say veterinary researchers, Dr. Susan Taylor and Dr. Diane Shelton of Saskatoon, Canada.

First signs occur between 7 and 24 months of age when such dogs normally enter heavy training. Affected dogs are usually described as being prime athletic specimens of the breed with an excitable temperament and lots of retrieving drive. There appears to be a strong hereditary connection.

Routine exercise — jogging, swimming, hiking or most waterfowl hunting — isn’t likely to induce an episode, whereas activities with continuous intense exercise and high anxiety such as upland game hunting and retrieving drills are.

Because the cause of exercise induced collapse is unknown, the best treatment consists of avoiding intensive exercise in conjunction with over-excitement or anxiety. Ask your veterinarian if your Labrador is at risk.