Heat Stress

In summer, animals need constant access to both water and shade, as heat stress can develop extremely quickly in hot weather. Your pet must also always stay cool, hydrated and safe.

With temperatures soaring, RSPCA NSW is urging pet owners to take steps to keep their animals cool and comfortable. Just like people, pets can quickly become heat-stressed or dehydrated in hot weather, which can lead to the dangerous condition known as heatstroke.

Heatstroke occurs when an animal’s body overheats and cannot cool down, leading to a life-threatening rise in internal temperature. This is an emergency that can cause rapid organ failure and even death if not addressed in time.

While dogs often get the most attention when it comes to heat risks, all companion animals – including cats, small pets like rabbits or guinea pigs, birds, and even fish – are vulnerable to heatstroke in the right conditions. By understanding the dangers and taking simple precautions, you can protect your furry and feathered friends from the summer heat and prevent heatstroke before it happens.

Heat Stress

Why Heatstroke is so Dangerous

Heatstroke is more than just “overheating” – it’s a severe condition where a pet’s body temperature rises to dangerous levels (hyperthermia) and the body’s cooling mechanisms fail. Unlike humans, who can sweat over most of our bodies, many animals have limited ways to cool down (for example, dogs mainly cool themselves by panting). If a pet cannot reduce their body temperature, multi-organ failure can occur rapidly.

Unfortunately, heatstroke often has a high mortality rate in pets like dogs if not treated immediately.

This is why prevention is critical – once heatstroke sets in, it’s a life-threatening emergency that requires veterinary care right away.

Recognising the Signs of Heatstroke

It’s important to recognise early signs that your pet is overheating so you can act quickly. Signs of heat stress or heatstroke can vary by species, but common symptoms to watch for include:

  • Panting or rapid breathing: Most pets will pant or breathe fast when they are too hot. In dogs, you might notice constant, frantic panting and an elevated heart rate. Cats may breathe with their mouth open (a sign of distress), and birds can pant with an open beak.

  • Excessive drooling or salivating: Dogs may drool more than usual. Rabbits and some other animals might salivate or have wetness around the nose/mouth when stressed by heat.

  • Lethargy, weakness, or confusion: Overheated pets often become weak, wobbly, or unresponsive. They might appear lethargic, lie down and refuse to get up, or seem disoriented. For example, a usually active rabbit lying stretched out and limp with very warm ears is a red flag for heat stress.

  • Unusual gum or tongue colour: In dogs, the gums or tongue may turn bright red or pale/greyish as circulation is affected.

  • Vomiting or diarrhoea: Overheating can cause digestive upset. A dog suffering heatstroke may vomit or have diarrhoea, which further dehydrates them.

  • Shaking, seizures, or collapse: In advanced heatstroke, pets may experience muscle tremors or even seizures. Eventually, they can collapse, become unable to stand, or lose consciousness.

If you notice any of these signs, move your pet to a cooler area immediately. Contact a veterinarian if you suspect heatstroke – it can escalate rapidly and every minute counts.

Pets at Risk: Who is Most Vulnerable?

Heatstroke can affect any animal given the right conditions, but some pets are at higher risk. Knowing the risk factors can help you take extra precautions for pets who are more vulnerable:

High temperatures and humidity: Hot weather is a primary risk – especially during heatwaves or humid conditions where it’s harder for animals to cool off.

Small pets (“pocket pets”): Rabbits, guinea pigs, ferrets, mice, and rats are highly susceptible to heatstroke due to their small size and high metabolic rate. They retain heat easily and struggle to cool down. These animals are often confined to cages or hutches, which can become heat traps if not properly cooled.

Brachycephalic (flat-faced) breeds: Dogs with short noses like Pugs, Bulldogs, Boxers, and Boston Terriers – and even flat-faced cats like Persians – have a harder time breathing and cooling by panting. Their airway structure means they cannot dissipate heat as effectively, putting them at greater risk of overheating.

Overweight or large breeds: Overweight pets overheat faster and have reduced capacity to cool down. Large, heavy breeds can also struggle in the heat, especially if they have thick fur.

Very young or senior animals: Puppies and kittens, as well as elderly pets, cannot regulate their body temperature as efficiently.

Underlying health issues: Pets with heart or respiratory problems, or those on certain medications, might be less tolerant of heat.

Exercise and overexertion: Physical activity generates body heat. A dog that loves to play fetch non-stop or a rabbit hopping in the sun can overheat if exercise exceeds their ability to cool off.

Poor ventilation or confinement: Any animal kept in an area with insufficient airflow or ventilation is at risk.

Being left in a car: One of the most dangerous scenarios is a pet left in a parked car on a warm day. Temperatures inside a car can skyrocket in minutes, even with windows cracked.

Keeping Pets Cool: General Tips for Hot Weather

Preventing heatstroke is far better than treating it. Here are some essential ways to keep your pets safe:

  • Provide plenty of fresh water at all times, keeping it in the shade and refilling frequently.

  • Offer shade and cool retreats for outdoor pets, and bring them inside during extreme heat.

  • Avoid the midday heat by walking dogs early in the morning or late in the evening.

  • Never leave pets in cars, as temperatures inside can reach dangerous levels in minutes.

  • Watch out for hot surfaces, as asphalt and concrete can burn paw pads.

  • Help your pet cool off with paddling pools, mist sprays, or frozen treats.

  • Keep pets well-groomed, brushing out loose fur to improve air circulation.

  • Use pet-safe sunscreen on exposed areas of light-coloured pets to prevent sunburn.

  • Ensure small pets and birds have ventilation, cool surfaces, and frozen water bottles to regulate their temperature.

First Aid: What to Do if Your Pet Shows Signs of Heatstroke

If you suspect heatstroke, act fast:

  1. Move your pet to a cool, shaded area immediately.

  2. Apply cool (not ice-cold) water to their fur, focusing on the belly, groin, and paw pads.

  3. Increase airflow with a fan or air conditioning.

  4. Offer small sips of water, but do not force them to drink.

  5. Contact a veterinarian immediately.

In summer, animals need constant access to both water and shade, as heat stress can develop extremely quickly in hot weather. You pet must also always stay cool, hydrated and safe.

Here are some tips to help your pet cool down during summer: 

  1. Provide extra bowls of water in case one is accidentally knocked over. 
  2. Give outdoor dogs takeaway containers filled with beef or chicken stock which has been frozen overnight. 
  3. Freeze half a bowl of water overnight and add half a bowl of cool water before giving it to your pet. 
  4. Provide extra shade areas in your backyard using shade cloths and shade umbrellas. 
  5. Let your pet play in paddling pools filled with water. Just make sure she’s always supervised. 
  6. Never leave your dog in the car, even with the windows down. She could die in as little as six minutes, as temperatures in a vehicle can rise to dangerous levels, even on mild days. Leaving the windows open, parking in the shade and tinting do not help to reduce the inside temperature significantly. 
  7. Always walk your dog in the early morning or late evening when it’s cooler. 
  8. Ensure your pet always has easy access to shade and water throughout the day. 
  9. Spray your pet bird with a mist pump spray bottle (only if she likes it!) or install a bird bath. Just make sure she’s always supervised. 
  10. If you have a small cat or dog, cool a ceramic tile or oven pan in the fridge or freezer, and put it out for him to lie on. 
  11. Give your pocket pet a little bag of ice wrapped in a small, wet towel. 
  12. Allow your outdoor animals to come inside the house to share the air conditioning or electric fan.

If you think your pet is suffering from heat stroke, please call an RSPCA veterinary hospital or your local veterinarian immediately. 

From routine health checks to specialised surgeries, our veterinary hospitals can help you provide your pet with emergency treatment and critical support.