Has any one experience of this? Apparently usually greyhounds but can be hunting and sled dogs. A bitch I bred (2yrs) very hard going had an episode yesterday undiagnosed but vet said could possibly be this. Symptoms sudden very high temperature and breathng difficulties, hunched back and difficulty walking. Occurred suddenly within about 15 minutes of fairly light work. OK now and temp started to drop within 3 hours. This is the second unexplained episode as an adult - last time ended up on a drip very ill again no idea what it was. We thought initially it was snake bite - always on a Sunday of course!