10/28/2025
🙌 Winter laminitis…. What is this all about? 🙌
FACT - Research has indicated that 80-90% of laminitis is caused by endocrine (hormone system) disease (link to research in comments).
While there are many disease pathways to laminitis, if a horse has autumn and winter laminitis in the northern hemisphere, I immediately consider two of the most common underlying causes:
1. Endocrinopathic or hormonally driven laminitis, and
2. Mechanical/trauma driven laminitis
Laminitis = disease of the lamellae resulting in a lack of healthy attachment between the coffin bone/inner foot and the outer capsule. These two causes are often connected due to hoof care failing to optimise welfare in horses, leading to hormone imbalances, however a horse with ideal hoof welfare parameters can succumb to endocrinopathic laminitis simply due to what is called the seasonal rise in ACTH (hormone) levels.
Why winter? Because of the following facts:
1. ACTH, a hormone, rises in late summer to late autumn, called the ‘seasonal rise’ and this results in insulin and glucose fluctuations in both normal and those with an PPID/Equine Cushing’s disease. Horses can develop laminitis during August to December including horses on a very consistent diet (eg, hay only, no changes in fructans in grass for example)
2. Rising ACTH hormone levels can stimulate the production of cortisol, the ‘stress’ hormone - produced naturally during periods of excitement, pain, exercise, fear, trauma, and when there are infections - think of the situations this might manifest?
3. Higher cortisol makes veins less responsive to vasodilators, which can trigger foot pain if there is impaired circulation.
4. Higher cortisol, if production is high and sustained, can impair immune function, induce insulin resistance (or make it worse if already present), create electrolyte abnormalities, and reduced protein utilization.
5. High insulin which can accompany insulin dysregulation is a known risk factor for laminitis
6. Poor hoof morphology is associated with poor posture and development, pain, lameness, and altered blood supply to the hoof, therefore at higher risk of BOTH endocrinopathic AND mechanical laminitis
7. Cool temperatures and frosty grass can trigger laminitis connected to hormone changes increasing the risk due to high sugars in frosty grass and impared circulation in the hoof
Identifying vulnerable horses at risk…
1. Age - older horses naturally have higher ACTH levels, although PPID has been diagnosed in horses younger than 10 year of age
2. Horses with hooves with less than ideal hoof morphology (form and function), therefore less than ideal welfare parameters (see photo and background research and studies) which will have altered circulation, sometimes permanently.
3. Horses with unhealthy and compensatory posture and development and therefore less than ideal welfare parameters (see photos and background research and studies) which will result in altered load and circulation to the hooves, and associated lack of ideal hoof morphology. A negative cycle can develop between hoof and body, body and hoof.
4. Horses with a genetic predisposition for endocrine disease (esp PPID/Cushing’s EMR - equine metabolic disorder - and IR - Insulin Dysregulation)
5. Horses with higher than ideal ACTH, all year round or during the seasonal rise
6. Horses given an inappropriate diet, management, and welfare states
7. Horses with hoof care imposed on them which perpetuates or causes sub optimal welfare state, identified via externally verifiable objective evidence of physiology, postural and behavioural welfare parameters
8. Horses in chronic pain, chronic stress, or sub optimal regulation of the autonomic nervous system - this might be recognised as sub optimal behavioural welfare parameters and is perhaps more prevalant in the population that you think!
I recommend horse owners test ACTH levels in any horse considered at risk, at least once a year. Pergolide/prascend is a drug which helps control ACTH levels and can help promote healthier homeostasis or regulation of all the horses systems, and reduce laminitis risks.
To help prevent seasonal rise laminitis or laminitis at any time of the year, hoof care and horse care which promotes optimum welfare in horses is advised. This typically involves:
1. Species and welfare focused management which allows for the expression of natural behaviour and optimises neuro-muscular health and healthy homeostasis
2. Diet which best meets nutritional needs and welfare of horses in all stages of their life
3. Informed decision making and advocacy for horses which supports welfare, and includes appropriate exercise, training, interaction, hoof care and other necessary interventions of domestic horses to meet welfare needs.
4. Avoiding stress or interventions which may challenge homeostasis
5. Avoid frosty grass and high carb diet
6. Protect hooves from low temperatures
As an evidence based, welfare focused integrated hoof care provider, my role is to help owners provide the best HOOF and HORSE care to support optimum welfare state in their horse.
This is why I base my assessment AND gauge the impact of management and other interventions imposed based on current welfare and changes in welfare parameters over time; indicating the overall welfare state of an individual equine.
While this post cannot unravel and explain everything about this complex topic, my hope is that it causes pause for thought, and careful consideration of horses during the seasonal rise of ACTH.
Vulnerable horses especially need extra careful consideration of hoof health during this time.
The most disturbing statement I hear (often) after a consult is this:
“I wish I had known this sooner… I would have changed my hoof care for my horse beforehand”…
Most horses are lame. This is established in studies (see details for some in the comments), and in my considered experience, from my own documentation and opinion, this is increasing the risk of laminitis and other welfare issues, which for most, can be either avoided altogether, or minimised in their impact on welfare.
You may believe your hoof care provider is optimising welfare, but they may not. Question everything, seek objective evidence of welfare parameters, and ask “can we do better for his horse?”.
To take accountability, requires one to actually be accountable. Don’t believe everything you hear or read about laminitis. Fact check, apply critical thinking and reach out to established organisations and professionals with a proven track record of supporting optimal welfare parameters and laminitis.
Please, for the love of horses, take extra care of your horse, and those in your care, not only during the seasonal ACTH rise, but all year round 💚
Www.holisticequine.co.uk - supporting and promoting compassionate equestrianism for the benefit of all 💚🙏🐴
