Every year, veterinarians treat hundreds of dogs suffering from heatstroke. And in most cases, heatstroke is entirely preventable.
If you enjoy hiking year-round with your dog, it is important to know how to answer the following questions:
- When is it too hot to hike with your dog?
- How can you help your dog keep cool on the trail?
- What are the early symptoms of heatstroke in dogs?
- How can you start treatment for heatstroke on the trail?
Planning ahead to prevent heatstroke in your dog is best, but knowing how to recognize and treat heatstroke may end of up saving a dog’s life.
When is it too hot to hike with your dog?
For most dogs, anything over 80° F is too hot to go hiking, unless your dog is acclimated to the heat and there will be plenty of shade and water.
A helpful resource for determining what temperatures are safe for your dog is the Tufts Animal Care and Condition Scale created in 1997 by Dr. Patronek. He uses the following outdoor temperatures as cut-offs for risk of heatstroke in dogs.
Of course, like any safety guide for temperatures in dogs, it is important to understand that each dog is unique and there is a big difference in heat tolerance among dogs. With that said:
- Add 1 point of risk if your dog is brachycephalic (meaning that your dog has a short nose, like a boxer or a boston terrier).
- Add 1 point if your dog is obese (or significantly overweight).
- Subtract 1 point if water is available
- Subtract 1 point if shade is available.
So for example, today I took my dog, Glia, for a hike at a local state park. It was 75 degrees out when we left, but the forecast was expected to get up to 83 degrees. Since 83 degrees is potentially dangerous, with a risk score of 4, I choose a hike that was both shaded and had intermittent access to a river for Glia to cool off in to help bring her risk score down.
I subtracted one point for shade to get to a risk score of 3. And then I subtracted another point for the intermittent river access and the water that I brought with to offer Glia during our hike. Glia is neither obese nor brachycephalic, so this brought the risk of our hike today to a 2: risk of heatstroke unlikely.
PetPlan has made a nice infographic of a similar temperature scale if temperatures in celsius make sense to you. For those of us in the United States, here are the rough Celsius to Fahrenheit conversions:
|32 ° C||89.6 ° F|
|28 to 31 ° C||82 to 88 ° F|
|24 to 27 ° C||75 to 81 ° F|
|20 to 23 ° C||68 to 73 ° F|
|16 to 19 ° C||61 to 66 ° F|
|12 to 15 ° C||54 to 59 ° F|
When determining if it is too hot to hike, it is also important to be aware that there are two types of heatstroke: Nonexertional and Exertional.
Nonexertional heatstroke occurs when dogs are exposed to increased environmental temperatures when they are not exercising. Examples include dogs left inside of a parked car or left in a yard on a hot day without shade or water.
Exertional heatstroke occurs during exercise. It is worth noting that this type of heatstroke is more common in dogs that have not been acclimated to their environment. So if you are traveling to hike in Utah over the summer, be aware that your dog who lives in Minnesota may not be able to tolerate the temperatures as well as a local dog.
It can take up to 60 days for a dog to acclimate to new temperatures, although most dogs are at least partially acclimated within 10-20 days.
The need for a dog to acclimate to temperatures also means that dogs are at a higher risk for exertional heatstroke in late spring or early summer before they become acclimatized to the high environmental temperatures.
In their article on heatstroke in dogs, Today’s Veterinary Practice notes that with proper acclimatization and knowledgeable handlers dogs can work in extreme temperatures. For example, military dogs have been known to work in temperatures reaching 140 ° F without adverse effects. And racing greyhounds can have transient rectal temperatures as high as 107.6 ° F after racing without showing signs of heatstroke. Of course, we don’t recommend that you take your pet dog anywhere near these extremes, but it is interesting information.
How can you help your dog keep cool on the trail?
There are several ways to help your dog stay cool and still hike during periods of hot temperatures. But the best way to keep your dog cool is to avoid exposing him to elevated temperatures in the first place. As the saying goes, an ounce of prevention is worth a pound of cure.
With this in mind, choose the coolest time of day for your hike. Yes, this may mean getting up early or staying out late, but if you avoid hiking in the heat of mid-day, you will significantly reduce your dog’s chance of overheating on the trail.
Keep your hikes short and make sure your dog is acclimated to warm temperatures before taking any longer hikes. And beware humidity. Humidity can decrease your dog’s ability to cool off.
When temperatures are elevated, also try to choose a trail with plenty of shade and water. Remember that chart from above? You can subtract 2 points if your trail has both shade and water.
Shade helps keep you and your dog cool by blocking solar radiation. While the air temperature doesn’t change, standing in direct sunlight (solar radiation) can make the air feel 10-15 degrees warmer than the actual temperature.
Hiking in the coolest part of the day and picking a trail with a lot of shade, helps prevent exposing your dog to environments that can heat them up. But when we begin to talk about subtracting a risk point for having water available, we are now talking about making sure your dog has a way to cool off.
There are four main ways that dogs can cool off: evaporation, conduction, convection, and radiation.
Water works to keep dogs cool mostly by evaporative cooling. Dogs utilize evaporative cooling in two main ways: panting and covering their body in water (such as after swimming).
Panting is a dog’s primary method of cooling off. Dogs don’t sweat like we do (except for certain small areas, like on their paw pads).
Panting works through evaporation, as heat is used to turn water in the moist mucous membranes of a dog’s mouth and nose from a liquid to a gas. Since panting relies on evaporation of water, it is important for a dog to stay hydrated for panting to be the most effective.
As a result, it is important to bring plenty of drinkable water along on any warm-weather hike to help your dog pant effectively.
It is also important to note that panting doesn’t work as well in conditions of high environmental humidity. Or for dogs who already have defects of the upper airway (which includes many flat-faced dogs). Humidity and upper airway defects increase the work of respiration and result in respiratory muscle activity generating more heat.
Letting your dog wade and swim in water can also utilize the power of evaporation cooling, as once your dog gets out of the water the heat (both environmental and that produced by your dog’s body) will evaporate the water on your dog’s fur before it begins heating your dog’s core body temperature up again.
Many dog gear products intended to help your dog stay cool on a hike are created to utilize evaporative cooling principles.
Examples of these type of cooling vests include Ruffwear’s Swamp Cooler and Jet Stream Vest, as well as Hurrta’s Cooling Vest.
The Ruffwear Swamp Cooler provides protection from the sun and cooling through evaporation. In warm climates, dogs typically stay cool by seeking shade during the heat of the day and moving around in cooler temperatures. The Swamp Cooler allows dogs to perform in hot climates. To activate the Swamp Cooler, soak in water, wring out and place on your dog. The light-colored fabric reflects solar radiation, while evaporative cooling pulls heat from the dog.https://ruffwear.com/products/swamp-cooler-dog-cooling-vest
Below are images for Ruffwear’s Swamp Cooler (left) and Jet Stream Vest (right). Both images are links to Amazon. (I am an Amazon Affiliate and earn from qualifying purchases).
Hurrta’s cooling vest and cooling harness, also both work via evaporative cooling. Only the cooling vest is available on Amazon currently. The image below is an Amazon link.
There is a little debate about how well these cooling jackets/vests actually work, but evaporation is a scientifically proven cooling method. For a brief overview of how well cooling vests work for dogs, check out this article by Vet Help Direct.
The second most common way dogs cool off is by conduction. Conduction occurs when heat transfers from one object another. When dogs are hot, they often lay with their abdomen (which has the lowest density of fur) against a cool surface. This allows heat from their body to transfer to the cool rock or grass beneath them.
If your dog is seeking shade to lay in during a hike, let them take some time to rest in the shade.
Water can also be a way for dogs to cool off via conduction. If the water is colder than the air temperature and your dog’s body temperature, a dip in the water can increase the conduction of heat away from your dog.
Conduction is made more effective in a warm dog, as the body moves more blood towards the body surface where it can be cooled more easily (this is called peripheral vasodilation). A well-hydrated dog will be better able to move their blood to the arteries and veins nearer the surface of their skin. Dehydration reduces a dog’s ability to do this. Yet another reason to keep your dog well hydrated while hiking.
And there is also gear that is made with the intent of staying cool against your dog’s skin (and blocking the heat of the ambient air against your dog’s body). One of these fabric technologies is Jade Cool. By infusing nano particles of jade (yep, the stone/rock) into clothing, theoretically your dog can stay cooler. Jade has a low thermal conductivity meaning that it absorbs heat slowly and takes a long time to heat up.
Insect Sheild makes a permethrin-treated dog tank-top with Jade Cool technology. We just received one of these from Insect Shield to try out this summer. Glia heats up easily from solar radiation (her black coat soaks up a lot of sunlight), so she would really benefit from some conductive cooling. The tank is also a bright pink which will hopefully reflect more light than her black fur. We will let you know how it works in a future blog post.
Convection occurs when air moves over a dog’s body to disperse heat. You can choose to hike on a windy day to increase convection, but you probably aren’t going to bring a fan along to increase convective cooling for your dog. Just like conduction, convection is more effective when warm blood is moved from internal organs to the blood vessels near the surface of the skin.
Cooling by radiation occurs when heat from the body dissipates into the environment. This is how solar radiation warms your dog – heat from the sun (which is so much hotter than either ambient air or your dog) dissipates into the environment. Cooling by radiation becomes less and less effective when ambient temperatures near your dog’s body temperature. Which is part of why higher temperatures can be dangerous for your dog to hike in.
What are the early symptoms of heatstroke?
The first symptoms of heatstroke are signs that your dog is trying to cool off. Panting that is increasing in intensity, shade seeking behavior, or water seeking behavior are all signs that you might need to slow down your hike. This is also a perfect time to offer your dog some water and give them a chance to cool off in the shade.
At this point, your dog is likely in a state of heat stress. His or her body temperature will be normal, but there is some discomfort and physiologic strain.
If you continue hiking or otherwise exercising your dog when they begin to experience heat stress, you risk your dog developing heat exhaustion and heat prostration. Your dog’s body temperature will begin to elevate, and you will start to see symptoms classically associated with heatstroke in dogs.
The most common signs of heatstroke reported by dog owners are excessive panting and inability or unwillingness to rise. Some dogs have vomiting and/or diarrhea, especially after drinking large amounts of water. Dogs may also exhibit hypersalivation (drooling), difficulty walking, muscle tremors, loss of consciousness, and seizures.
At this point, if you can’t cool your dog off quickly, your dog could die from heatstroke as their body temperature rises above 106 ° F. (For reference normal body temperature in a dog is between 99.5 to 102.5 ° F).
How can you start treatment for heatstroke on the trail?
Unfortunately, it is much easier to prevent heatstroke than it is to treat heatstroke in dogs. But here are some things you can do to try and cool your dog off as rapidly as possible.
- Get your dog wet! Lukewarm water is best, as ice-cold water can cause the vessels near the skin to constrict and reduce the ability for cooling via the methods discussed above. Make sure your dog’s paws and abdomen stay as wet as possible, as water will evaporate away from the non-furred areas the fastest.
- Get your dog out of the sun to reduce increased heating via solar radiation. If you have a cool surface to lay your dog on while transporting them, try to get your dog’s lightly furred abdomen resting against the coolest surface.
- Try to get a breeze moving over your dog to increase convective cooling.
- Then get your dog to a veterinarian as soon as possible. Emergency treatment is needed in cases of heatstroke to lower your dog’s body temperature back below 103 ° F. It may also be needed to treat complications that can develop after your dog develops heatstroke.
Heatstroke in Dogs
Quick recognition and prompt care can save your dog’s life, but the best treatment is prevention. All dog owners should be educated on heatstroke prevention and symptoms in dogs. For more information on heatstroke in dogs, check out the following resources (which we reviewed before typing up this blog post).
- DVM 360: “Heatstroke in Dogs”
- Today’s Veterinary Practice: “Heatstroke in Dogs”
- “Pathophysiology of heatstroke in dogs” research article by Y. Bruchim, M. Horowitz, and I. Aroch
- Urban Search and Rescue Veterinary Group: “Heatstroke in Dogs”
And for some related reading on Pawsitively Intrepid, check out our review post of different dog water bowls made for use on hiking trails. These are great to bring along to keep your dog hydrated on the trail.
Happy Hiking Everyone!
Kate and Glia