Horse toads: a serious condition, but not cancer

An alarming foot condition that is causing concern

Deep necrotizing pododermatitis, also known as toad's foot, is a dreaded condition of the horse's foot, characterized by its slow, painful progression and frequent recurrences. It affects the frog , sole , and sometimes the bulbs of the heel, with characteristic signs: blackish tissue, foul odor, persistent moisture, and deep cracks.

Some severe forms of hoof cancer can give the impression of a tumor due to the extensive tissue damage. Hence a common question among owners: " Does my horse have hoof cancer?"

The toad is not a cancerous tumor

It is important to reassure people: the toad is not a cancer.

• This is not a malignant tumor.
• There are no cancer cells and no risk of metastasis.
• The appearance of the foot may be alarming, but this is the result of chronic and deep inflammation, not cancer.

Hoof thrush is an inflammatory disease of the hoof , often caused by anaerobic bacteria or fungi that thrive in poorly drained tissues. Over time, this inflammation can become self-perpetuating, leading to destruction of the horny tissues, separation of the hoof wall, and collapse of the hoof structure.

An autoimmune link? Atypical forms to watch out for.

In some very specific cases, the toad-like reaction could be linked to an excessive immune response in the horse against its own damaged tissues. This is referred to as a local autoimmune component, although this remains poorly understood and difficult to demonstrate scientifically .

These cases often involve horses that:

• They experience relapses despite conventional treatment.
• They present other signs of immune dysregulation (e.g., dermatitis, sarcoids, uveitis).
• They have a foot that reacts badly to regrowth, with abnormal keratinization.

It is tempting then to suggest an autoimmune origin, that is to say an immune system which goes into overdrive and attacks the body's own cells — in this case those of the hoof.

Can an autoimmune disease be diagnosed through a blood test?

This is a common question from owners: " Can a blood test confirm an autoimmune disease in a horse?"

The answer is no. To date, there is no specific blood test in horses that allows for the formal identification of autoimmune markers as is done in humans or dogs (e.g., antinuclear antibodies).

That said, a blood test can still be useful:

• To check if there is systemic inflammation ( fibrinogen level, SAA level, etc.).
• To rule out other pathologies.
• To explore the general immune response (e.g. , hypergammaglobulinemia on electrophoresis, leukocyte count...).

But none of these tests currently allows for a formal diagnosis of equine autoimmune disease.

So what can be done to treat a deep toadstool?

Even though toadstool disease is neither a cancer nor an officially classified autoimmune disease, it requires serious and appropriate management. Here are the main points:

• Thorough cleaning and deep sanitization .
• Avoid occlusive products that prevent exudates from escaping.
• Use ozone treatments with needles or gas to disinfect, reduce inflammation and promote healthy horn regrowth.
• Adjust the trimming and free the necrotic tissues to allow ozone or natural products to penetrate.

In some horses, conventional treatments fail, andozone treatments (such as Bagging or ozonated oils) then allow for real progress, even in recurrent cases.

In summary – What you need to remember

• The toad is not a cancer, even in its deepest forms.
• This is a chronic inflammation of the hoof, sometimes aggravated by an excessive immune reaction.
• No blood test can diagnose equine autoimmune disease to date.
• A rigorous protocol of local care (ozone, cleansing, drainage) allows for complete recovery in the vast majority of cases.