When working outside with your dog, you and your dog will be exposed to the weather and sun. Heat stroke is a life-threatening condition for your dog, and you should be able to recognize the warning signs, and know how to prevent it. Even on a cool day, if it is very sunny and your dog is working hard, or is a dark-coated breed, it can get overheated. Remember – dogs have a body temperature that is higher than yours!! Dogs get hot very quickly, long before you will.
There are certain signs to watch out for, that might indicate heat exhaustion in your dog. In particular, unusually rapid panting, and/or a bright red tongue or mucous membranes. The dogs primary mechanism for cooling off is through panting. Since this cooling process uses evaporation, the dog will require more water when it is panting heavily. shorter-nosed breead like Bulldogs or Pugs may have a less efficient heat exchange rate, so should be watched especially closely.
If you suspect that your dog is overheating, stop immediately and get it into shade. Check with your vet for the best ways to coold down an overheated dog.