Horses are mammals like people, yet their ability to withstand much colder temperatures makes them ideal companions. Their thick winter coat helps retain heat when necessary while their internal furnace can create warmth when needed.
Horses generally can survive most winter weather provided they remain metabolically healthy, receive enough calories and shelter. However, certain factors could pose challenges.
The Fur Coat
Winter fur coats provide horses with protection against cold temperatures and snowfall, made up of two distinct kinds of hair: longer, stiffer guard hairs and a softer undercoat that trap air for insulation purposes. Furthermore, this natural oil coating repels water while sheding raindrops; therefore it is wise not to bathe or brush your horse too frequently in winter as too much brushing strips away these protective oils that repel raindrops and shed raindrops.
Hairs have a special structure that enables them to stand up, or piloerection, when resting, helping increase thickness of haircoat and provide insulation. At cold temperatures, metabolic rates increase to produce energy and heat that dissipates through respiratory tract and legs/tail/ears/hooves; legs below knee/hock have less muscle to keep warm than muscle therefore require less energy than keeping warm via muscle. Furthermore, their legs have blood-shunting mechanisms which divert circulation toward hooves/head when resting to avoid frostbite.
Healthy horses typically can tolerate cold temperatures and deep snow as long as they’re out of the wind, typically reaching down to -40 degrees Fahrenheit when dry; wet snow presents greater difficulties, often causing them to shudder and even cause health problems in some cases.
As such, it’s vital that your horse has some form of shelter on days with precipitation. Shivering caused by cold and wet weather is not caused by hunger; rather, it is simply their reaction to feeling cold.
Your horse should only require blanketing if the temperature falls well below freezing, when their coat provides enough protection from the elements to provide insulation against colder climates. A breathable blanket may offer additional insulation against harsh elements.
The Hooves
Horses have thick winter coats to keep themselves warm in cold temperatures. Even so, their hooves still experience freezing due to being made mostly from tendons and bone which do not hold as much insulating moisture than muscles do; when their lower extremities get cold it causes their hooves to freeze up too fast, potentially weakening them or exposing their inner structure to fungal infection.
Therefore, it is vitally important to closely inspect hooves during cold weather to make sure they remain in good shape. Horses who spend all year out tend to better tolerate the chilly climate than those housed indoors; nonetheless, both types should still have plenty of high quality hay available and protection from wet snow and ice.
To maintain body heat, horses generate internal heat and send blood away from its extremities to its core. Horses that are in poor body condition or suffering from laminitis may not produce enough of this internal heat and experience symptoms of cold weather on their feet; for healthy horses this should rarely become an issue.
As horses adapt to cold weather conditions, their bodies begin to produce more sweat than usual, leading to damp and wet skin which fosters the development of fungi that will eat away at their hoof material and deteriorate it further. If they’re blanketed up as well, this extra sweat could potentially create damp skin conditions that promote mold growth on blanketed horses’ coats, potentially encouraging it to ferment into hoof fungus that destroys hoof growth and causes further issues with hooves and hoof condition deterioration resulting in hoof erosion and degradation of hoof material which will then feed back onto keratinous material on hoof walls creating damp areas under blankets where mold forms an infestation occurs in turn creating damp skin conditions which then promotes mold to grow eat away at its base material slowly over time affecting hooves which in turn promotes further damp and wet which promotes further damp and wet which then encourages mold growth that further promotes this process further and contributes further damp and wetness that causes damp skin to become damp causing damp skin to become damp resulting in damp environments which encourages fungus which causes degradation to keratinous material within hoof structure which leads to its destruction keratinous material that makes up its base material to get exposed due to overexposure over time and ultimately harm the hoof surface due to being covered up from moisture leakage through gaps created when being covered up from both side and wet environments which lead to it getting exposed.
Hoof trims should be carried out regularly on horses to prevent potential issues like laminitis and sole sensitivity from developing, while extra moisture from rain and sleet may soften its structure and expose it to potential microbial invasions.
At times, horses may experience frostbite on their ears, tails and other extremities if exposed to cold temperatures or plant toxins such as ergot or endophyte-infected fescue grasses that hinder circulation to these parts. Therefore, it is crucial that horses receive enough iodine through either trace mineral salts or an iodized grain supplement in order to prevent hypothermia and cold intolerance.
The Muzzle
Equine muzzles are filled with blood and do not freeze like human noses can. Their ears are also protected due to thick fur around their ears that protects against frostbite; and an ample thermoneutral zone makes horses particularly well adapted for cold temperatures as long as they can access enough food and water.
The hindgut of an equine acts like an enormous furnace, burning grass into energy that fuels their bodies while simultaneously warming them from fermentation. This steady supply of energy allows a horse to remain warm in extreme winter weather as long as there is adequate hay or fibrous feed available to them. Unfortunately, restricted horses who cannot graze slowly often inhale large quantities of sugars faster than their bodies can manage, leading them down the path toward colic and laminitis, or even unexpected sugar overloads that leave them vulnerable against colic or laminitis symptoms.
As they eat, horses consume large amounts of water along with their food, creating heat as the digestive process works to break it down and burn calories to digest it.
As long as horses can use something to drain this excess moisture from their bodies, it should be no problem – wet snow can provide just such an avenue, soaking into their fur coat and helping them shed heat more efficiently.
One important consideration when it comes to winter horse care is recognizing that long, dense haircoats may prevent halters and bridles from fitting as comfortably as in summer when horses shed their warmer coat. This may cause discomfort and irritation to both horse and rider as the incorrect fit may irritate or rub in undesirable places on the animal’s body.
The Ears
Horse ears can also become uncomfortable due to the cold. Hairs around their ears may tuck under ice or snow and create an air pocket, leaving the horse’s core cold despite feeling warm underneath. This may give the illusion that their core temperature has become lower.
Before returning horses back into their winter stalls, it’s wise to let them shed. This will help avoid this happening and keep their ears warmer.
As well as fat reserves, horses develop thick winter coats to provide insulation. This usually indicates they are eating enough, however due to lack of calories or digestive issues some horses are unable to develop an appropriate winter coat and must be blanketed during this season.
As soon as a horse encounters cold temperatures, their instinctive reaction is to seek shelter from wind and rain or gather with other animals for warmth. When foraging is interrupted due to cold temperatures, eating more hay will help retain heat within their bodies and keep shivering to a minimum – another natural response which helps generate heat while protecting muscles from becoming cold.
Horses will use piloerection to increase the thickness of their winter coat. Horses also restrict blood flow to their extremities to help minimize heat loss while secreting thyroid hormone that increases metabolism and internal body heat production.
Assuming a horse has access to adequate shelter, energy reserves, good condition and has developed a thick winter coat, it should have little difficulty in weathering a harsh winter without needing extra support such as extra blankets or water sources. However, in certain situations more assistance might be necessary and this might include extra blankets or extra hay/water supplies.
A horse’s nutritional needs depend on their size, condition, temperature, diet, exercise regimen and breed. Always provide clean, fresh ice-free water at all times to promote proper hydration and ensure adequate water intake during cold weather months. Monitoring hydration levels closely will also aid with water intake.