Border Collies are very energetic dogs and will give their all to a task even to the point of exhaustion. Border Collie Collapse (BCC) is an episodic nervous system disorder induced by strenuous exercise. There is a genetic mutation involved and working in hot weather is a factor as well. This gene mutation, DNM 1 associated exercise-induced collapse, is also present in Chesapeake Bay Retrievers, Curly-coated Retrievers and Pembroke Welsh Corgis.
Since your dog doesn’t know when to stop, it’s up to you to keep watch to prevent overexertion. The combination of heat and strenuous exercise can cause collapse. If you regularly exercise your dog vigorously, (jogging, hiking, etc.), there’s a good chance your dog won’t feel the effects of BCC. But it’s not a guarantee.
Signs in a dog experiencing BCC occur 5-15 minutes after exercise. The dog becomes disoriented, sways, staggers, has a stiff gait, may fall to the side and appears not to be able to focus. The dog usually recovers after about 30 minutes without any further problems. However, dogs that have another episode need to be seen by a veterinarian. They should not take part in competitions or work.