If you own mice or a hamster, or you’re considering adopting these tiny pets, you may or may not be aware of a dangerous state that mice and hamsters can enter, called torpor. 

While torpor is an important adaptation for wild mice and hamsters, it can be dangerous for pets. Pet mice and hamsters aren’t exposed to the same environmental stressors as their wild counterparts, and as a result, their metabolisms aren’t properly adapted to safely enter and exit a torpid state. 

In this article, we’ll discuss why torpor can be dangerous for pet mice and hamsters and what pet owners can do to prevent it.

What is Torpor in Mice and Hamsters?

Torpor is a temporary state of reduced metabolic activity that is commonly observed in a wide range of animal species, including mice and hamsters. 

Torpor allows animals to conserve energy during periods of food scarcity or environmental stress, and it is characterized by a decrease in body temperature, heart rate, and breathing rate. It is similar but not identical to hibernation.

When mice or hamsters enter torpor, they reduce their metabolic rate by as much as 90%, which allows them to conserve energy and survive for long periods without food. 

Torpor is typically induced by a combination of environmental cues, such as a lack of food or cold temperatures, and hormonal signals, such as changes in the levels of the hormone leptin.

How Does Torpor Work?

Torpor in mice and hamsters is a complex physiological process that involves a number of different changes in the body. 

One of the most important changes is a decrease in body temperature, which helps to conserve energy by reducing the amount of heat that is lost to the environment. 

During torpor, mice and hamsters can reduce their body temperature to as low as 12°C (54°F), which is well below their normal body temperature of around 37°C (99°F).

In addition to reducing body temperature, torpor also involves a decrease in heart rate and breathing rate. This helps conserve energy by reducing the amount of oxygen and nutrients the body needs to survive. 

During torpor, a mouse or hamster may breathe as few as one or two times per minute, and their heart rate can drop to as low as 50 beats per minute.

Is Torpor Dangerous for Pet Mice and Hamsters?

Yes, torpor is a dangerous condition for pet mice and hamsters and can lead to death. 

Torpor is not necessarily dangerous for wild mice or hamsters because they are adapted to this natural response to environmental stressors such as cold temperatures and limited food availability. 

In contrast, pet mice and hamsters are typically kept in a controlled environment with consistent temperatures and food availability, so they are not adapted to torpor.

Wild mice and hamsters have evolved physiological mechanisms to enter and exit torpor safely, such as the ability to slow down their metabolic rate and conserve energy during torpor, as well as the ability to quickly return to a normal metabolic state when environmental conditions improve. 

Wild mice and hamsters are more likely to enter torpor in response to environmental stressors that they encounter regularly in their natural habitats, and are therefore better equipped to handle the physical and metabolic changes that occur during torpor.

Pet mice and hamsters, on the other hand, are not exposed to the same environmental stressors as their wild counterparts and may not have the same physiological adaptations to torpor. If a pet mouse or hamster enters torpor, it may struggle to maintain proper metabolic function and may become dehydrated or malnourished, which can lead to serious health complications.

In summary, while torpor can be a natural and adaptive response for wild mice and hamsters, it can be dangerous for pet mice and hamsters because they are not adapted to this state and may experience negative health consequences if they enter it.

What Causes Torpor in Pet Mice and Hamsters?

Torpor can be dangerous for pet mice and hamsters, so it’s important to know what can cause this condition in a pet mouse or hamster so that you can try to avoid it. 

Here are some situations that can potentially cause torpor for pet mice and hamsters: 

Cold temperatures

Mice and hamsters are susceptible to torpor when they are exposed to cold temperatures for an extended period of time or sudden drops in temperature. They may become lethargic and unresponsive, with a decreased body temperature.

Illness

Some illnesses, such as infections or metabolic disorders, can cause mice and hamsters to enter a state of torpor as their bodies try to conserve energy to fight off the disease.

Stress

Chronic stress can also cause mice and hamsters to become torpid as their bodies try to cope with the demands of a stressful environment.

Dehydration

When mice or hamsters are dehydrated, their bodies may enter a state of torpor to conserve water.

Malnutrition

A lack of food or nutrients can also cause mice and hamsters to become torpid, as their bodies try to conserve energy until food becomes available.

Learn more: Best Food for Mice in the US

What Does Torpor Look Like in Pet Mice and Hamsters?

When a mouse or hamster is in torpor, its metabolic rate slows down, and its body temperature drops. It’s important to be able to recognize the signs of torpor in mice or hamsters if you own or are planning to own these pets in the future. 

If you are concerned that your pet mouse or hamster may be in torpor, or if it is exhibiting any other unusual behavior, it is best to consult with a veterinarian who specializes in small animals. 

We will also include some immediate steps you can take if you suspect your mouse or hamster is in torpor in a later section.

Some signs that a mouse or hamster may be in torpor include:

Lethargy: The animal may appear unusually inactive or slow-moving.

Decreased body temperature: A torpid mouse or hamster may feel cool to the touch, as its body temperature drops to conserve energy.

Reduced breathing: The animal’s breathing may become shallow or slow.

Unresponsiveness: The mouse or hamster may not respond to stimuli, such as touch or noise.

Decreased appetite and water intake: A torpid mouse or hamster may not show interest in food or water, as its body is conserving energy.

How to Prevent Torpor in Mice and Hamsters

Mouse and hamster owners can take a number of steps to prevent torpor. First, it is important to provide mice with a clean and spacious cage that is kept at a consistent temperature. 

Here are some tips for preventing torpor in pet mice and hamsters:

Maintain a consistent temperature

Mice and hamsters are sensitive to changes in temperature, so it’s important to keep their environment at a consistent temperature. The ideal temperature range for pet mice and hamsters is between 65-75°F (18-24°C).

Provide plenty of food and water

Mice and hamsters need a steady supply of food and water to maintain their metabolism and avoid torpor. Make sure to provide fresh food and water daily, and monitor your pet’s food and water intake to ensure they are getting enough.

Provide ample bedding 

Mice and hamsters need a comfortable and clean place to sleep, so provide ample bedding in their enclosure. For mice, the bedding should be changed frequently to prevent the buildup of waste and bacteria. Hamsters rarely need complete bedding changes.

Give your pet plenty of exercise

Mice and hamsters are active animals and need plenty of exercise to maintain their metabolism and avoid torpor. Provide toys and structures for your mouse to climb and play on, and give them plenty of space to run around. Make sure that your hamster or mice have a wheel to exercise on at night. 

Monitor your pet’s health

Regularly monitor your mouse for signs of illness or discomfort, such as lethargy, loss of appetite, or weight loss. If you suspect your pet is experiencing health problems, seek veterinary care as soon as possible.

Learn more: Diabetes in Small Pets: Know the Risks and the Signs

What to Do if Your Mouse or Hamster Enters Torpor

If you suspect your pet is in torpor, it’s important to act quickly to help them recover. 

As soon as you can, call your veterinarian and ask what you should do next. You might need to take your pet in for an exam and health check, even if they appear to come out of torpor. 

Here are some steps you can take if you think your mouse or hamster has entered a state of torpor: 

Gradually warm your pet

If the mouse or hamster is in a cold environment, move it to a warm location and gradually warm it up by providing a heat source, such as a heating pad set to a low temperature or a warm water bottle wrapped in a towel. 

Do not expose the mouse or hamster to sudden changes in temperature, as this can be stressful and potentially harmful!

Tip: It’s a good idea to keep a microwavable pet heating pad on hand in case of emergencies like torpor and illness.

Provide fluids

A torpid mouse or hamster may not feel like drinking water, but it is important to keep them hydrated. Offer room-temp water in a shallow dish or dropper, and provide small amounts frequently. 

You can add a small amount of salt and a small amount of sugar to the water to provide additional hydration. If needed, use a syringe to administer fluids, but make sure to do so carefully to avoid choking.

You can also offer high-water-content foods, such as fruits and vegetables, to help hydrate the mouse or hamster. Make sure that any foods and fluids you offer are not cold. 

Provide nutritious foods that are rich in protein

Offer your mouse high-protein treats such as mealworms, scrambled eggs, chicken, or dog kibble. This can help restart your mouse or hamster’s metabolism and bring them out of torpor. 

Monitor your mouse or hamster during and after torpor

Keep an eye on your pet’s behavior and physical condition, and consult with a veterinarian if you have any concerns. If the mouse or hamster does not show signs of improvement after several hours or if it appears to be in distress, seek veterinary care immediately. 

Keep your pet with you and in a warm, safe environment until they begin eating and drinking on their own.

Provide a quiet and stress-free environment

Reduce noise and disturbances in the mouse or hamster’s environment to help it feel calm and comfortable. Offer a cozy nest box or hiding place to provide a sense of security.

Make changes to the enclosure

Try to identify what caused your pet to enter torpor. Often, this is an environment that’s too cool. We recommend keeping a thermometer and humidity monitor next to your pet’s cage or tank to monitor their living conditions. 

Make sure your pet’s enclosure has plenty of bedding and spots to nest. If you notice that the area around the enclosure is consistently too cool, place a space heater in the area or attach a tank heating pad if you’re using a glass tank. Use a heating pad with a thermometer attached to control the heat coming from the heating pad.

Torpor in Mice and Hamsters is Important to Understand

Torpor is a crucial adaptation for wild mice and hamsters, but it can be dangerous for pets. Mouse and hamster owners can prevent torpor by providing them with a clean and spacious cage, a balanced diet, and a consistent temperature. 

Monitoring pet mice and hamsters for signs of torpor and providing appropriate care is also vital for preventing health problems related to torpor. With proper care and attention, pet owners can help their pet mice or hamster to stay healthy and active.

Sources: 

Hrvatin S, Sun S, Wilcox OF, Yao H, Lavin-Peter AJ, Cicconet M, Assad EG, Palmer ME, Aronson S, Banks AS, Griffith EC, Greenberg ME. Neurons that regulate mouse torpor. Nature. 2020 Jul;583(7814):115-121. doi: 10.1038/s41586-020-2387-5. Epub 2020 Jun 11. PMID: 32528180; PMCID: PMC7449701. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7449701/

Gavrilova O, Leon LR, Marcus-Samuels B, Mason MM, Castle AL, Refetoff S, Vinson C, Reitman ML. Torpor in mice is induced by both leptin-dependent and -independent mechanisms. Proc Natl Acad Sci U S A. 1999 Dec 7;96(25):14623-8. doi: 10.1073/pnas.96.25.14623. PMID: 10588755; PMCID: PMC24486. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC24486/