Rabbits are mammals, and they are warm-blooded animals like all mammals. It means that their body temperature does not fluctuate in response to changes in the ambient temperature. It occurs in cold-blooded animals such as fish, which can withstand the freezing temperatures of the seas and oceans because their body temperature changes in tandem with the temperature of the seawater. But that’s not the case with warm-blooded mammals.
Rabbits and humans are both warm-blooded; thus, they both experience cold. The only difference between ourselves and them is that rabbits are better at withstanding cold temperature extremes than humans are. This is because nature has endowed these wild creatures with temperature-regulating capabilities that enable them to withstand extremely cold temperatures. But! There will undoubtedly be a temperature that is beyond their tolerance. To learn more, read the article below.
What Cold Temperatures Can Rabbits Tolerate?
Rabbits look like small animals who are extremely innocent, fragile, and sensitive. Yes, they are, but they are quite tolerant of cold temperatures. They can easily tolerate temperatures of about 40 degrees Fahrenheit (4 degrees Celsius). They can even tolerate extreme temperatures drop, even 28 degrees Fahrenheit (-2 degrees Celsius).
How Do Rabbits Tolerate Temperature Drops?
Rabbits are warm-blooded animals with a constant body temperature of 102 to 103 degrees Fahrenheit (38 to 39 degrees Celsius). Well, doesn’t a question arise, how do the rabbits retain their body heat in such cold weather? The answer relies upon the mechanisms they utilize for thermoregulation of their bodies. Some of the major mechanisms are as follows:
Thick Fur Coat
Rabbits have fine insulating skin. It can be evidenced by a study showing the thermal properties of rabbit skin robes and blankets. They turned out to be warmer than ordinary wool. On top of such warm skin, rabbits have a furry coat. It is quite thick and contributes to maintaining the body temperature by not letting the outside cold air come in contact with the body.
Many people wonder what the newborn baby bunnies would behave that have no fur on them. Until 12 days of their age, when they start growing fur, healthy adult rabbits shed their fur from the sides and the lower portion of the abdomen and place them in the nest box (wild rabbits place them in their warren) to keep the infants warm. Moreover, baby bunnies have brown fat just under the skin that plays a major role in keeping them warm.
Rabbit’s body has adapted numerous ways to maintain the temperature. Piloerection turns out to be one of them. To understand it in easy words, we can also call it goosebumps. It is a state in which the hairs on the surface of the body become erect in response to a number of stimuli that cause the underlying muscles to contract. The erected hairs then trap the air in between them and form a layer of air between the skin and the outside cold environment. Air is an excellent insulator that neither lets the body warmth leave the body nor lets the outside freezing temperature disturb the internal system.
Rabbit ears also help them stay warm in the winter months. This is because they employ a mechanism named vasoconstriction. It is referred to as the narrowing of the blood vessels. As they narrow down, their exposure to the outside environment reduces, resulting in decreased heat loss. Though this mechanism happens in other body parts, too, it is the most obvious in their ears.
The opposite of vasoconstriction occurs when the temperature is too hot. The blood vessels dilate mainly in the ear and in the other parts of the body too. The surface area for heat exchange increases, and more body heat is lost to the outside environment. This mechanism is called vasodilation.
When rabbits are suddenly exposed to extremely cold weather, they start shivering just like humans. One doesn’t need to worry about it as it is a normal cold temperature response. The constant vibration of the muscles breakdown the energy molecules of the body, producing heat and keeping the rabbit warm.
Release of Adrenaline
Adrenaline is a hormone that is secreted by the adrenal glands situated about the kidneys. This hormone produces a “fight or flight” response in the body and enables the rabbit to cope with all types of stresses, including temperature extremes. Whenever the rabbit’s body temperature will alter due to the extremely hot or freezing temperature in the surroundings, adrenaline will try to normalize it. In cold stress, adrenaline will cause constriction of the blood vessels, thus retaining the body heat due to the reduced blood flow towards the skin. Moreover, it will increase the breakdown of glycogen into glucose in the liver. As a result, more glucose will be broken down in respiration, and hence more metabolic heat will be generated in the body.
What Temperature Is Considered Too Cold for Rabbits?
Rabbits can tolerate temperatures up to 25 or 30 degrees Fahrenheit, but they cannot tolerate temperatures as low as 20 degrees Fahrenheit (-6 degrees Celsius). This temperature is too low for rabbits to tolerate. Therefore, these animals need a proper hutch to keep them safe from the harsh weather in such temperatures.
How to Design a Hutch for Outdoor Rabbits?
When the temperature is below freezing, there are greater chances of rain and snowfall during winter. Rabbit cages made out of wood would not be a great idea to keep outside. Wood gets wet easily and takes time to dry. If you want to keep the rabbits outside the home in the winter season, it would be great if the cage is made up of plastic by placing bricks underneath to give it support. Plastic or other waterproof material will also protect the rabbit from many diseases as many wet conditions can cause diseases like pneumonia in them. To give the rabbit a clear vision of the outside and to let the natural light enter the hutch, you can use clear perspex on one side of the hutch. A hutch made of cardboard box won’t be able to suffer a harsh storm, so never opt for it.
The water bottle kept in the hutch can get frozen due to the extremely low temperature. It would be a great idea to replace the previous water bottle with fresh water after a few hours.
The ground will be cold and outdoor bunnies might not sleep properly at night or during the middle of the day. So it would be better to place an old blanket on the ground, which would be soft to snuggle on and give warmth to the pets. But remember, the blanket should not replace the hay bedding.
How to Design a Hutch for Indoor Rabbits?
Some bunny owners want to keep their rabbits inside the house. To keep the rabbit indoors, you can opt for one of the following two ways; you can either buy a cute little hutch or sacrifice one of your rooms for the rabbits. As the body temperature of the rabbits is almost close to that of the humans, the temperature of the home maintained through a passive heating system, heaters, or a fireplace would be enough to keep you and your bunnies warm inside the house.
Remember that a rabbit cannot survive excessive heat. You might be feeling extremely cold and want to spend your entire day by a fireplace, but your rabbit might not want it. Don’t force him to accompany you in a room in which they might feel hot.
If you think your rabbits are shivering or feeling too cold, you can provide them with some heating pads, but usually, there is no need for that. To maintain a natural environment, you can let some of the fresh air in by letting the window open for some time; they can surely survive a cool breeze. But they might not survive suffocation or unnecessary warmth in the room.
Do I Need to Change the Food?
You don’t need to change their food like hay, vegetables, and leaves that are perfect. All you need to do is provide them with some extra food. It will help the rabbits produce more energy in their body to cope with the cold weather.
Moreover, hay is used for making the bedding for bunnies. Not only do rabbits eat their bedding, but it also keeps them warm. Hence, providing a lot of hay as bedding can help rabbits stay warm.
Hypothermia in Rabbits
As the name indicates, hypothermia is a condition in which the temperature of the body falls below normal. Though the normal body temperature of bunnies is close to 102 and 103 degrees Fahrenheit, they are efficient at a body temperature of 60 to 65 degrees Fahrenheit too. The temperature below this range is too cold for rabbits and becomes the cause of hypothermia. It may occur if the rabbit’s body becomes wet due to rain or moist wind and is not given proper care.
Signs of Hypothermia
Bunnies start shivering to keep their body warm. But exposure to cold temperatures for a prolonged period of time makes them lose their energy, and in severe conditions, they might stop shivering or might show no movements at all. They show no coordination at all, and the lips and the gums turn pale.
Frostbite in Rabbits
If a rabbit is left in a chilly environment for a long period of time with little or no shielding from the wind, frost, and water, he may show the signs of frostbite. The major injury due to frost is usually seen on the tips of the rabbit’s ears. But, in addition to these, frostbite can affect other areas of the skin, especially the feet of the rabbit if they are sparsely furred.
If your bunny gets soaked from the rain and accidentally experiences temperature drops below freezing, he will most likely suffer from frostbite and hypothermia. Extremely low-temperature shock, especially in baby bunnies, can sometimes lead to numbness of the body and can be fatal in such cases.
Yes, a rabbit does feel cold, but it can tolerate a great temperature drop. Wild rabbits and other healthy adult rabbits kept as pets can endure temperatures from 60 degrees Fahrenheit to as low as 25 degrees Fahrenheit. Temperature close to 20 degrees Fahrenheit or lower than this is too cold for rabbits.
The Winter season that makes everything frozen or brings rain or moist cold wind with it is fatal for bunnies. If a rabbit is exposed to such harsh weather for a long period of time, it can cause hypothermia or frostbite in them. Both the conditions can be fatal if left unchecked.
Take proper care of the bunnies in cold weather, whether indoors or outdoors. Insulate the house rabbits live in and give them a lot of food to eat.