Having suffered heat stroke before that should have required hospitalization (I was out in the middle of no-where, about 5 hours drive from the nearest medical clinic), I can say that it really doesn't take long at all for heat to overwhelm you. We had no A/C and no real way to cool me off at the time, so they literally tossed me in the lake to get my core temperature down. It was terrible recovering from that, and to this day heat just 'gets me' a little faster than other people.
That's.... horrible to hear about those dogs. That's awful! Oh my goodness![]()