When horse owners think about laminitis, most picture lush spring grass.

But surprisingly, winter can also be a high-risk time for horses prone to metabolic laminitis.

Cold weather brings together two important risk factors that many owners don't realise can occur at the same time:

• Fluctuating sugar levels in winter pasture, and
• Reduced blood flow to the hooves caused by cold temperatures. 
  

For horses with Equine Metabolic Syndrome (EMS), insulin resistance or PPID (Cushing's disease), this combination can be enough to tip the balance.

It's Not Just Spring Grass

Many people assume winter pasture is "safe" because it isn't growing rapidly.

Unfortunately, that's not always true.

Cold, sunny days can allow grasses to accumulate sugars, particularly when overnight temperatures are low. Those sugars may remain elevated throughout the day, making winter pasture capable of triggering insulin spikes in susceptible horses.

This is why metabolic horses should still be carefully managed throughout winter, even when the paddocks don't appear particularly lush.

 

Cold Weather Changes Blood Flow

Winter affects horses in another important way.

When temperatures fall, horses naturally reduce blood flow to their legs and feet to conserve body heat. This process—called vasoconstriction—is completely normal in healthy horses.

However, horses with metabolic disease often already have compromised circulation.

Reducing blood flow even further means the delicate tissues inside the hoof may receive less oxygen and fewer nutrients, potentially increasing the severity of laminitis.

Some studies have even found that although fewer horses may develop laminitis during winter in certain regions, those that do are more likely to experience severe disease.

Why Blood Flow Matters

Healthy hoof tissues rely on an excellent blood supply.

Blood delivers:

• Oxygen
• Nutrients
• Hormones
• Cells involved in tissue repair 

When circulation is compromised, the hoof's ability to maintain healthy lamellae may also be affected.

This is one reason why maintaining healthy circulation is an important part of managing horses at risk of laminitis.

 Jiaogulan and Healthy Circulation

One herb that has attracted considerable interest is Jiaogulan (Gynostemma pentaphyllum).

Its naturally occurring compounds, known as gypenosides, have been shown to stimulate the production of nitric oxide within the lining of blood vessels.

Nitric oxide is one of the body's most important natural vasodilators. It encourages blood vessels to relax, allowing blood to flow more freely through the circulation.

It also acts in opposition to endothelin-1, one of the body's strongest blood vessel constrictors. Endothelin-1 has been found to be elevated in horses with endocrine-related laminitis, making vascular support an area of growing interest in metabolic horse management.

While Jiaogulan is not a treatment for laminitis, it may provide valuable nutritional support for healthy circulation, particularly during periods when cold weather naturally reduces blood flow to the extremities.

More Than Just Blood Flow

Jiaogulan is also classified as an adaptogen.

Adaptogens are herbs that help the body adapt to physical and environmental stress by supporting normal regulation of the stress response.

Because stress hormones such as cortisol can influence insulin regulation, maintaining a healthy stress response may be another useful consideration for metabolically challenged horses.

Winter Management Tips

If your horse has EMS, insulin resistance or PPID, winter management is just as important as spring.

Consider:

• Restricting access to frosty or high-sugar pasture
• Feeding a balanced, low-sugar forage diet
• Maintaining appropriate mineral balance
• Encouraging regular movement where comfortable
• Supporting healthy hoof circulation

The Take Home Message

Winter laminitis is often overlooked, but cold temperatures and changing pasture sugars can create the perfect storm for susceptible horses.

Supporting healthy circulation, maintaining excellent nutrition and carefully managing pasture access are all important parts of a comprehensive winter management plan.
For horses with metabolic disease, laminitis prevention isn't just a spring conversation—it's a year-round commitment.