A dog’s primary cooling system is exchanging the hot air inside with hopefully cool air outside, through panting. If your dog is lagging behind and/or panting heavily, he is likely overheated and trying to cool himself down.
Dogs, unlike us humans, do not have sweat glands to cool themselves down. I equate dogs with old Volkswagens, as they are “air-cooled”. Giving your dog water is helpful, but shade and a cool breeze is what they really need to cool down. Please be mindful, we sweat to stay cool but that’s not how our dogs function and similar to a toddler, dogs cannot tell you they are hot or tired, so please keep your parent hat on and be vigilant with your observations.
Dogs natural hunting hours are dawn and dusk, which is their most active time of the day and it is no coincidence that these are the sun’s least intense hours. So if you are walking your dog and the weather is warm, consider finding shade about every 15-20 minutes, depending on the circumstances. I’d prefer to keep dogs from ever overheating so I tend to stop more frequently then necessary, as I’d rather error on the side of caution. Keep in mind that hiking in the middle of the day when there is no breeze and no shade could easily overheat your dog. Also, walking your dog on cement is much cooler than asphalt; please always touch the ground to test the temperature before your dog walks on it. If your dog is overheating, in addition to shade and a cool breeze, you can pour water over your dog’s head and body to help cool down the brain and other organs. Never, ever leave your dog in a closed vehicle; even on a cooler day the inside heat can rise to detrimental levels for your dog.
Every year I have clients who’s dogs suffer or pass out from heat stroke because they are simply unaware of these simple tips. I hope that with this information you and your dog can protect yourself year-round.