BCC, formerly called Exercise Induced Collapse (EIC), is a neurologic disorder in which strenuous exercise may trigger a collapse episode. The EIC name has been assisgned to a similar but genetically different condition in the Labrador and several other breeds. The type common in Border Collies and also seen in Australian Shepherds is different. Several collie-type breeds are affected. Other descriptions of the disease are exercise induced hyperthermia, stress seizures, and “the wobbles.”
Dogs with the BCC will become disoriented, confused, sway, stagger, or even fall to the ground after a few minutes of vigorous exercise. During an episode a dog will make exaggerated vertical movement of its legs while walking. If turning its legs may cross over each other. It may also scruff its feet along the ground. Hot temperatures, elevated excitement in the dog, and intensity of exercise may all contribute to triggering episodes. A few won’t show signs until a a few minutes after exercising. Episodes may last from a few minutes to a half-hour, after which the dog returns to normal. Activity will need to be limited for affected dogs and if it has been active in competitive physical events it should be retired.
BCC is probably inherited, though there is not currently any specific information on how it is passed or what genes might be involved. Because it is different from the form seen in Labradors, the DNA test for Labrador EIC cannot be used in Aussies. Affected dogs should probably be withdrawn from breeding and certainly should not be bred tight on their own pedigrees or to dogs with affected relatives.