Horse Hoof Thrush: Causes and Treatment

Thrush is a bacterial infection of the horse's frog and sulci that causes foul-smelling discharge, tissue destruction, and significant lameness if untreated.

Key Facts

Thrush is caused by anaerobic bacteria including Fusobacterium necrophorum that thrive in wet, dirty conditions
The frog and deep clefts of the hoof are the primary infection sites, producing a characteristic black, malodorous discharge
Horses kept in wet, poorly drained, or infrequently cleaned environments are most at risk
Deep-seated thrush can invade sensitive laminar tissue and cause significant lameness
Treatment involves debriding affected tissue, applying topical antiseptics, and improving hoof care and environment

Welfare Considerations

Thrush causes genuine discomfort and can progress to severe lameness. Horses with advanced thrush may show pain on hoof pressure even before lameness develops. The condition is largely preventable through basic management, making it a welfare issue closely tied to owner education and husbandry standards.

What You Can Do

Pick and clean hooves daily, removing manure and debris from frog clefts
Ensure turnout and stable areas have adequate drainage and are not chronically wet or muddy
Apply topical thrush treatments to affected areas and expose clefts to air where possible
Consult a farrier or vet if thrush has penetrated deeply or is causing lameness