Horses are far more tolerant of cold weather conditions than we tend to give them credit for. Just because we may think it is excruciatingly cold out, it does not mean that our horses agree. There is generally no need to keep a horse confined to the barn or their stable during winter, because they are adapted to survive outside in the cold.
Horses can comfortably live at temperatures of 18°F (-7°C). If they have access to shelter, they can tolerate temperatures up to -40°F (-40°C). Without shelter they can tolerate a little less than 0°F (-17°C). Cold-blooded horse breeds, like Icelandic or Yakutian horses, can tolerate -70 °F (-58°C).
Many factors affect a horse’s capacity for dealing with cold conditions. Overall body condition has been shown to play a greater role in determining how much cold a horse can endure than the breed. Horses have a variety of physical and physiological adaptations to survive even the coldest winters.
What is a Horse’s Lower Critical Temperature?
Lower critical temperature refers to the minimum temperature a horse can naturally tolerate, below which they require extra energy to maintain their core body temperature.
There are a range of factors that dictate a horse’s lower critical temperature: fur length, body size, their overall condition and whether they have been acclimated to cold conditions.
How Cold Can Horses Tolerate?
Horses with a winter coat generally have a lower critical temperature of around 18°F (-7°C). Without access to shelter, but in dry conditions with no wind, horses can tolerate temperatures a little lower than 0°F (-17°C). If they have access to a stable or shelter, they can tolerate extremely cold temperatures of up to minus 40°F (-40°C).
Horses are Adapted to Handle the Cold
Even though some breeds of horses are specially adapted to living in cold conditions, all horses, even warm-blooded breeds, are well adapted to thrive in cold weather.
There is no need to keep horses wrapped up in insulated blankets or in a toasty, warm barn all winter. They are able to regulate their own body temperature, thanks to their metabolism, their thick winter coat, and the way that their blood circulates around their bodies.
Digestion Keeps a Horse Warm
When horses eat forage, the bacteria in their gut digest the cellulose and release a large amount of energy in the form of heat. The heat of digestion helps to regulate the horse’s core body temperature.
Foods that are high in fiber, like hay and oats, release the greatest amount of heat when digested, compared to low-fiber foods like barley or corn. Thus, it is important to feed a horse lots of high fiber feed just before and during the cold winter months.
Horses Grow a Winter Coat
During autumn, horses begin to grow their winter coat. It is longer and denser than their summer coat to insulate them against cold temperatures. This is why most horses appear fluffier during winter.
Each hair on a horse’s body is connected to a tiny muscle in their skin, called the erector. When it is cold, the muscles contract, making their hair stand up straight. A layer of warm air gets trapped against the horse’s skin, buffering them from the cold.
If a horse gets too hot, the muscles relax again, and the insulating layer of air will disappear, allowing the body to cool. This mechanism is called piloerection.
Winter Fat Reserves
During autumn, horses eat a lot to put on weight and build their fat reserves. In winter, horses have an extra layer of fat under their skin that provides them with even more insulation to protect them from the cold.
Limited Blood Circulation to Extremities
Horse’s bodies are built for surviving the cold. Their legs have adapted to have very little soft tissue that needs blood supply. The result is that the vast majority of the blood in a horse’s body remains in their core.
When blood is pumped to extremities, like the tail and legs, it cools quickly, but if it remains in the trunk of their body, it stays warm.
How to Care for a Horse During Winter
Even though horse’s bodies are well adapted to deal with cold weather, there are some things that horse owners can do to keep their horses healthy and happy during the icy winter months.
- Provide shelter for horses to get out of the wind and rain. A stable or barn is not necessary; horses just need a three-sided, covered structure that will keep them dry and out of the icy wind. If a building is not an option, a line of trees that acts as a windbreak is sufficient. Having access to shelter greatly increases a horse’s cold tolerance.
- Ensure that they have plenty of unfrozen water. Horses cannot meet their water intake requirements by eating snow, and it can lead to colic or gastrointestinal problems. Horses should be provided with warm water, between 45 and 65°F (7 to 18°C), to encourage them to drink more in winter.
- Put plenty of food out for them. Horses expend a lot of energy to keep their bodies warm. Hence they need to eat more calories during winter. Provide lots of high-fiber feed, like grass, hay and barley.
- Pick snow out of their hooves daily. When there is heavy snowfall, snow and ice will gather around horse’s hooves. When the snowballs get very heavy, they make it difficult for the horse to walk, and it stresses the joints and tendons in their legs. Remove snow that packs into the hoof regularly.
- Watch out for ice in paddocks. Horses can cause themselves serious injury by slipping and falling on ice in their paddock. Spread a fine layer of wood ash over icy areas to speed up the melting.
Putting a Blanket on a Horse
Horses survived for thousands of years without the extra warmth of a blanket. Contrary to popular belief, putting a blanket on a horse at the first sign of inclement weather is not a good idea. It actually impedes the horse’s ability to acclimate to winter temperatures.
A horse’s winter coat is perfectly sufficient for keeping them warm, and if they have access to shelter and can stay dry and out of the wind, there is no reason to blanket them.
One should only blanket a horse under the following conditions:
- If a horse is body clipped, they no longer have their winter coat and should be covered with a waterproof turnout blanket if they are going to be spending a cold winter day in the paddock. After exercise, they should also be covered with a quilted blanket, but only after they have been dried of sweat.
- If a horse is not yet well acclimated to the cold and there is a sudden drop in temperature, it will benefit from the extra warmth a blanket provides. The blanket will need to be changed every day and at night according to the fluctuation in temperature.
- If it is raining hard and they are struggling to stay dry. Moisture causes the hair to stick to the skin and does not allow the hair to trap a warm layer of air to insulate the horse. Dry the horse thoroughly before putting a banket on to avoid trapping the moisture on their skin.
- If a horse is underweight and has a low body condition score, they will benefit from a blanket, because they do not have enough fat reserves to maintain a warm enough body temperature.
Cold Weather Horse Breeds
Warm-blooded Arabians, Saddlebreds, Quarter Horses, and Thoroughbreds need extra pampering during chilly winter months. But there are some horses that have been bred specifically for living in very cold conditions.
Icelandic horses are one of the oldest breeds in the world. The Vikings introduced them to Iceland when they settled there late in the 9th century.
They are a small breed of horse, generally standing between 12 and 14 hands high, weighing between 730 and 840 pounds (300 to 380 kilograms). Due to their small size, robust bone structure, and thick double coat these horses are extraordinarily hardy and cold tolerant. They can withstand freezing winds and snowstorms with temperatures as low as minus 22°F (-30°C).
Originating from the Yakutia region of Siberia, which is well known for its harsh, deep winters, Yakutian horses not only survive but thrive in temperatures that plunge to minus 70 °F (-58°C) It is often around minus 13°F (-25°C) in mid-winter.
Yakutian horses arrived in the region around 800 years ago, between the 13th and 15th century, when the Yakut people migrated there. They are not direct ancestors of the Neolithic horses that evolved in Siberia. However, it is remarkable that Yakutian horses have adapted to survive in these extreme conditions in only 8 centuries – a very short time span in evolutionary terms.
They are short and stocky in stature (13 hands tall on average), with a very thick, dense winter coat that reaches 8cm in length. Their fur traps a thick layer of warm air against their skin to insulate them from the cold. Yakuts also have the ability to locate green, edible vegetation under deep snow.
Their metabolisms are adapted to the seasons in Siberia. In autumn, they develop their fat reserves, and during winter, their metabolic rate slows. It increases again in spring when there is vegetation to feed on.
This breed was developed in the Ural Mountains of Russia, where winter temperatures can get as low as minus 40°F (-40°C) in the south and minus 76°F (-60°C) towards the north.
Like the Icelandic and Yakutian horses, Bashkir horses are a small breed, standing on average 14 hands high. They have a unique curly coat that grows longer and thicker during winter but sheds in summer to allow the horses to survive the very hot summers in the Urals.
Finn horses, as their name suggests, were bred in Finland. These horses are cold hardy to withstand the freezing Scandinavian winter months where temperatures get to minus 60°F (-51°C)
A small breed, standing 15 hands tall, on average, they have strong, muscular bodies, covered in a thick coat of fur to keep them warm.
Horses have always been central to Mongolian culture and daily life. Mongolian horses are a short, muscular breed that generally stands between 12 and 14 hands tall. They weigh between 500 and 600 pounds (226-272 kilograms).
These horses are not kept in pastures with shelters and are extremely cold tolerant. Temperatures during Mongolian winters regularly drop to minus 40°F (-40°C) and the horses can easily tolerate this.
Can Horses Die from Cold Weather?
Even the most cold-tolerant horses can succumb to extremely cold weather conditions. Some winters near the Arctic are much harder and longer than others, and these bitter winters can cause hundreds, if not thousands of horses to perish.
During the winter of 2009 and 2010, over 180 000 horses died of exposure on the Mongolian steppe. A combination of wet and windy conditions, and deep snow that kept horses from finding food, caused this mass death. There is very little that herdsman can do to save horses in these extreme conditions.
If a horse is exposed to heavy rain and wind, its fur soaks all the way through, and it loses its ability to trap a warm layer of air close to its skin. If this happens and a horse is not able to forage due to deep snow, it will not be able to regulate its core body temperature. This puts a horse at risk of dying.
There is no need to pity horses that live outside during the cold winter months. Horses can tolerate extremely low temperatures that we could never imagine being outside in. They have a thick winter coat that traps a layer of warm air against their skin.
Horses’ lower critical temperature is 18°F (-7°C), meaning that at temperatures less than this, they use extra energy to maintain their body temperature. If they are dry and there is no wind, horses can tolerate temperatures of 0°F (-17°C) without shelter. With a shelter available, they can tolerate up to minus 40°F (-40°C).
Certain breeds of horses are even better adapted to dealing with extreme cold. Icelandic, Yakutian, Mongolian, Bashkir and Finnish horses are known as cold-blooded breeds. They have been recorded to survive temperatures as cold as minus 70 °F (-58°C).
If a horse’s coat gets soaking wet from rain or sleet, it compromises its ability to thermoregulate. Strong winds also decrease the insulating ability of their winter coat. Owners should only blanket their horses if it is completely necessary.