By Emma Purnell, RVN Cert.Nut.
Animals that are small have a much lower tolerance for the extremes of temperature, as they will match the environmental changes much more rapidly. It means they can quickly become hyperthermic, even if originally from hot climates.
The ideal temperature range for several common small mammal species are listed below:
- Rabbits – 15-21°C
- Guinea pigs – 17-20°C
- Hamsters – 20-22°C
- Gerbils – 20-24°C
- Rats – 19-23°C
- Chinchillas – 10-15°C
- Degus – around 21°C
Heatstroke (or hyperthermia) is a very serious problem for any species. When body temperature rises too high, several body systems can rapidly fail, including the gastrointestinal tract and, more seriously, the brain. If the brain becomes too hot damage rapidly occurs, leading to brain damage, seizures and death. Heatstroke is an emergency – prevention is better than cure.
Outside enclosures should be out of direct sunlight and in an area, which allows for good ventilation. Outside pets, especially those, which are white (even in patches) or ‘sunbathe’ can be at risk of sunburn. Pet safe sunblock should be applied, especially to rabbit ears but follow all product instructions carefully. Using stone or ceramic tiles in the shade can be beneficial as they will always feel cool. If the pet is kept indoors, they need to be in a shaded area of the house, away from direct sunlight and in the coolest room possible. Good ventilation through the room and enclosure will keep the temperature down. Using thermometers to measure ambient temperature is useful, but it is not advised to place them in the enclosure due to the risk involved with them being chewed.
For both indoor and outdoor pets, active methods can be used to help cool them. There are solid plastic cool packs specifically designed for pets, or frozen plastic bottles of water, but both of these must be covered with a specifically designed cover or towel before being used. The pet must have plenty of space to move away, they should never be forced to be in contact with cool packs. These cool packs will also cool the environmental temperature and do not need to be in contact with the pet to be useful. If the pet begins to chew the cool pack it must be removed. Fans and air conditioning can be great to improve ventilation but should never be directly angled at the pet and any electrical cables should be well out of reach. Placing ice packs safely behind the fan can cool the air they are pushing towards the enclosure. Placing a cool, wet towel over a section of the enclosure can help to cool the air within but ensure it is not dripping water and is not able to be chewed and ingested. Using spray bottles to mist the area within the cage with cool water will help but do not directly spray the pet.
Animals can become dehydrated very quickly in hot weather so providing plenty of cool, fresh water and ensuring it is always accessible is a necessity. Increasing water intake by providing fresh fruit or vegetables (ensuring they are safe for the species) can be of use, rinsing or soaking the treat before giving it can increase the water intake further. Freezing fresh fruit or vegetables to give to small pets can be a good way to increase water intake, cool and keep them active but care should be taken to supervise them when they have treats like this.
If a pet is overheating (or hyperthermic) there are a few signs you may see. These include:
- Very rapid and shallow breathing
- Quiet or lethargic behaviour
- Ears being hot to the touch and more red than normal
- Moisture around the nose
- Salivating
- Throwing back the head and open mouth breathing
- Acting disorientated
- Seizures
If you see any of these signs then you must seek immediate veterinary attention as overheating can be rapidly fatal, but there are some steps you can take. The most important thing to remember is NOT to cool them too rapidly. Bathing is not recommended in many small animal species as it can lead to shock and this is even more of a risk if they are hot and placed in cold water. Using cool (not cold) water to dampen the ears can be helpful – they use the blood vessels in the ears to regulate temperature as they are very close to the surface so this can lead to a reduction in body temperature. Make sure they have access to cool water to drink as this will help to cool them but do not syringe or force them water – stress will only push their temperature higher.
Emma qualified as a Veterinary Nurse in 2008 and works for nutravet (UK) Ltd. She has a BSc in Zoology with Animal Ecology and an MSc in Ecology, helping to fuel her interest in more exotic species. She has a particular love of small furries and has a grade A distinction in Canine and Feline Clinical Nutrition (CertNut).
