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Not only do humans suffer from the increasingly erratic weather patterns, but so do nature, animals, and, of course, our horses.

The so-called “summers of the century” with temperatures soaring well above 30°C for weeks, coupled with months of scarce precipitation, have become all too common. Occasionally, a summer that is excessively cold and overly rainy sneaks in, leaving us shivering instead of sweating.
The same can be said for winters: sometimes they don’t happen at all. Incidentally, this phenomenon is also the reason behind the surge of Mediterranean diseases in our regions. Insects, which serve as intermediary hosts for these pathogens, no longer perish due to the absence of sub-zero temperatures. And when winter does finally arrive, it often brings an excess of snow, causing roofs and trees to buckle under the heavy load.

Temperature regulation in horses

One of our favorite pastimes as humans is complaining about the weather. However, we have simple remedies at our disposal: when it’s cold, we can turn up the heating or wear a thicker jacket. And when it’s too hot, we can switch on the air conditioning or take a refreshing swim.
For our equine companions, things are a bit more complicated.
Of course, they do enjoy a broader range of temperatures within which they feel comfortable, and an even wider one in which they can adapt without issue.
Their hormonal system plays a key role in this, regulating what happens to the available energy in their bodies.
Thus, during the annual autumn coat change, their metabolism shifts into “winter mode,” releasing more energy as heat, effectively warming them from the inside out. Consequently, horses tend to be less active in winter, preferring to consume hay to convert the absorbed energy into heat rather than engaging in movement. When spring brings about a change in their coats, their internal thermostat shifts back to “summer mode.” Less heat is produced, but they can produce sweat to cool down their bodies. Just as we enjoy taking a shower on a hot summer day without immediately drying ourselves off to experience a pleasant cooling effect.

How do changing weather conditions affect horses?

Horses generally adapt well to natural temperature variations, thanks to their hormonal system and the ability of their coat to adjust to different conditions. However, the weather has become increasingly unpredictable. Some years seem to prolong winter with persistently cold temperatures extending well into early summer. During these times, the internal heating mechanisms of the horses has already turned into summer mode, their winter coats have already been shed. Accordingly, the horses start to freeze. This is often resulting in cold-related illnesses that can still afflict stables in May or June. Additionally, visits to the osteopath or physiotherapist may become necessary as horses experience muscle stiffness, a consequence of the cold temperatures. Conversely, there are summers where one day may have seen temperatures soaring to 35°C, and people sought relief in every available spot of shade. Then, seemingly out of nowhere, there is a significant temperature drop, and suddenly it’s 20 degrees colder. Horses that were sweating in the scorching heat just yesterday may find themselves shivering. This is because their hormonal system doesn’t respond as swiftly to abrupt changes in environmental conditions.

How can I help my horse cope with abrupt weather changes?

Sudden cold

First and foremost, pay close attention to your horse’s signals. They will clearly indicate when they are feeling too cold.
They may become less active, seek shelter in the stable, have extended “warm-up phases” at the beginning of riding sessions, and display a visibly unhappy or “pinched” facial expression. This discomfort is usually exacerbated by cold, rainy, and windy conditions.
Their muscles might feel stiff, as if everything is contracted. To understand what’s happening, think about how humans react when they’re cold: we hunch our shoulders, curl our arms and body, minimize our size, and seek shelter behind walls, bushes, buildings, or trees to shield ourselves from wind and rain. It’s apparent that we wouldn’t feel like going for a jog in such conditions. If you notice your horse struggling with low temperatures, consider using a blanket for a few days. It doesn’t have to be an ultra-thick, heavyweight blanket. Often, a simple rain blanket is sufficient to shield the horse from wetness and wind, allowing an insulating air cushion to form in their coat. Once the inclement weather passes, you can safely store the blanket away.

Sudden heat

On the flip side, temperatures can unexpectedly soar. This is especially tricky when it has been cold for a few days or weeks and suddenly the sun is blazing out at 30°C again. This can pose challenges for many horses’ circulatory systems. When horses are preparing to warm themselves in colder weather and suddenly encounter warmth, it can lead to circulatory issues, potentially causing colic. Signs of circulatory colic may include weakness, apathy, a desire to lie down (often without rolling), and a prolonged capillary refill time. You can check the capillary refill time by lifting the lip sideways and pressing your finger on the gum for about 3 seconds. When you remove your finger, a light spot should quickly turn pink again, usually within one second. If it takes longer, it’s considered a prolonged capillary refill time. If you’re unsure, try it on several lively and healthy horses to establish what is “normal” versus “prolonged”. This can help you gauge your horse’s condition and act accordingly.

Braunes Pferd wird mit Wasser abgespritzt
© Rita Kochmarjova / Adobe Stock

The same rule applies to circulatory colic as it does to any colic: Alert the vet immediately.

While waiting for his arrival, you can already support the circulation with caffeine. To do this, rub some soluble coffee (not the decaffeinated kind, of course!) onto the mucous membrane of the mouth. Caffeine is permeable through the mucous membrane, allowing it to enter the bloodstream directly in the mouth and stimulate circulation. It’s crucial not to delay calling the vet and take prompt action because prolonged waiting can lead to a halt in intestinal peristalsis, resulting in entirely new and severe problems. Therefore, as with any colic, it’s better to act quickly and call the vet one time too many than to risk the horse’s well-being.

Absolutely avoid: abrupt feed changes

Feeding a mash is not advisable during such weather changes.
In fact, it represents an abrupt change in the horse’s diet, which can place significant stress on the digestive system and metabolism. Mash doesn’t provide internal warmth (the largest internal heater is still the large intestine with its microbial fermentation of hay), nor does it promote more effective peristalsis when the horse is dealing with circulatory issues.

For horses that consistently struggle with such weather changes, it’s advisable to complement a species-appropriate diet and minimize stress as much as possible by regularly supporting their cardiovascular system with specific treatments. Particularly during the autumn and spring seasons when weather changes are most severe, you can aid the heart muscle by administering L-Carnitine. Nature also offers excellent natural helpers, such as hawthorn (Crataegus). You can provide it as a dried herb in intervals or plant it along the fence surrounding the paddock or trail. This allows horses to nibble on the plant, benefiting from nature’s health offerings.

It is now well-established how crucial maintaining a healthy and diverse intestinal flora, as well as a stable neutral pH in the large intestine, is in preventing many diseases, ranging from laminitis to sweet itch. Consequently, it’s imperative to avoid one-sided shifts in the large intestine microbiome caused by certain feeds.


The increasing unpredictability of weather patterns affects not only humans but also horses and their well-being. The adaptability of their hormonal system through changes in their coat allows horses to manage natural temperature fluctuations to a certain extent. However, unexpected weather extremes, such as cold spells in summer or sudden heatwaves following cold periods, can pose challenges and result in health issues for horses. To assist horses in dealing with these situations, it is advisable to engage in mindful observation, provide adequate protection, maintain appropriate feeding practices, and seek veterinary support when necessary.