Foot abscess (also called interdigital abscess or bumblefoot) is a significant cause of lameness in sheep, causing acute pain and welfare compromise. Distinguishing foot abscess from footrot and other lameness causes is essential for correct treatment and welfare outcomes.
Causation
Foot abscess typically results from puncture wounds to the coronary band or interdigital space, or from Fusobacterium necrophorum infections that penetrate deeper structures. In some cases, infection tracks from the white line or sole. Unlike footrot, foot abscess is not primarily caused by Dichelobacter nodosus and does not spread as contagiously.
Clinical Signs
Affected sheep present with acute, severe lameness often involving a single limb. Swelling above the hoof (at the coronary band) is characteristic. Pus may be visible tracking from the coronet. The sheep is reluctant to bear weight and may adopt tripod posture. Systemic signs (fever, inappetence) can occur in severe cases.
Diagnosis
Clinical examination distinguishing coronary band swelling (abscess) from interdigital tissue damage (footrot, CODD) is essential. Paring the foot under safe restraint identifies the pus-filled cavity. Bacteriology can confirm causative organisms but is rarely required in field settings.
Treatment
- Pare and drain the abscess carefully under clean conditions
- Systemic antibiotics (procaine penicillin, amoxicillin) for 3–5 days
- Non-steroidal anti-inflammatory drugs (e.g., meloxicam) to reduce pain and inflammation
- Foot bandaging to protect the wound during healing
- Housing on clean, dry bedding during recovery
Welfare Priorities
Early detection and prompt treatment are critical — affected sheep should never be left untreated as foot abscess causes severe acute pain. NSAID analgesia should accompany all treatments. Farm recording of lameness cases enables identification of management factors (rocky terrain, wet conditions, overcrowding) contributing to incidence.
Prevention
Minimising trauma to feet (avoiding rocky, frozen, or debris-strewn surfaces), maintaining clean housing and pasture conditions, and prompt treatment of any foot lesion reduce foot abscess incidence. Footbathing with zinc sulphate targets footrot but has limited direct effect on abscess prevention.