What thrush is
Thrush is a bacterial infection affecting the frog, the elastic V-shaped structure in the middle of the sole. The bacteria involved are anaerobic: they thrive where oxygen does not reach, that is in the deep sulci of a foot kept in a damp, dirty environment.
The horn tissue of the frog progressively breaks down, the sulci deepen and fill with blackish material. It is a common problem and manageable in most cases — but if neglected it can reach deeper tissue and become painful.
How to recognise it: the four signs
- The smell: strong, sweetish and putrid. It is the earliest and most reliable sign — anyone who has smelled it once recognises it forever.
- Black discharge: dark, moist, sticky material coming out of the sulci with the hoof pick.
- Deep sulci: the grooves either side of the frog get deeper; the pick goes in where it used to meet firm tissue.
- Crumbling frog: the horn loses firmness, frays and peels away in soft flaps.
Why it appears: almost always the environment
Thrush is not bad luck: it is the consequence of specific conditions, and almost all of them sit outside the foot.
- Dirty or wet bedding: urine and faeces create the damp, oxygen-free environment anaerobic bacteria thrive in. This is cause number one.
- Feet picked out rarely: without a daily hoof pick, soil and organic material stay packed in the sulci for days.
- Lack of movement: the foot “pumps” as the horse walks. A horse standing in a stable has reduced circulation in the foot and a less stimulated frog.
- Muddy paddocks, especially in rainy seasons and during thaws.
- Conformation and shoeing: contracted heels and narrow sulci trap more material; some shoeing set-ups reduce frog contact with the ground.
No product can beat wet bedding: the first treatment for thrush is done with the fork, not with the tub.
What to do, step by step
- 1. Fix the environment: dry, clean bedding every day, paddock drainage where possible. Without this step everything else is temporary.
- 2. Pick the foot out thoroughly, every day: hoof pick into every sulcus, brush for the residue. It takes consistency, not force.
- 3. Have the foot assessed by the farrier: broken-down horn needs to be removed so air can reach the sulci. That is their job, not one to do yourself with a knife.
- 4. Keep it dry and protected: after cleaning you need something that absorbs residual moisture and limits recontamination until the next pick-out.
- 5. Keep the horse moving: movement on dry ground stimulates circulation in the foot and helps the frog firm up again.
The role of clay in the foot
On the frog the logic is the same as for galls: not to cover, but to dry and keep clean. Clay absorbs excess moisture and discharge, keeping the frog environment drier between one cleaning and the next — which is exactly the condition anaerobic bacteria cannot tolerate.
Fettone Plus is the dedicated Miraclay treatment: a clay preparation with absorbent and natural antibacterial action, with a plastic consistency that makes it ideal as a packing under pads or with therapeutic shoes. It is used in cycles, after picking out the foot.
For daily maintenance of the foot — barefoot or shod — Cavalli Scalzi combines clay, activated vegetable charcoal and vegetable tar to strengthen horn and sole and support the natural protection of the foot.
Frequently asked questions about thrush
- How long does it take to resolve?
- A superficial case improves within 1-2 weeks of a dry environment and daily cleaning. Full reconstruction of the frog horn takes months, though, because the tissue grows back slowly: the smell disappears long before the shape returns to normal.
- Can the horse work with thrush?
- In superficial cases yes, and movement actually helps. If there is lameness, pain on pressure or bleeding during cleaning, work must stop and a veterinary assessment is needed.
- Is it contagious between horses?
- Not in the classic sense: the bacteria involved are common in the yard environment. If several horses are affected at once, the problem is not contagion but the shared condition — bedding, drainage, foot management.
- Why does it always come back in the same horse?
- Usually for two reasons: a foot conformation that traps more material (contracted heels, narrow sulci), or a cleaning routine less regular than you think. In the first case the work is done with the farrier on the shape of the foot.
- Aggressive or gentle products?
- Very aggressive disinfectants also damage healthy horn tissue and can slow down the rebuilding of the frog. The approach that holds up over time is daily mechanical cleaning, a dry environment and an absorbent product that does not attack the horn.
In short: thrush is beaten with management before products. Dry bedding, feet picked out every day, a regular farrier and an absorbent clay between cleanings resolve the vast majority of cases — and when lameness or pain appear, the call to the vet comes before anything else.