Interdigital necrobacillosis (Foul in the Foot) is an infection of the skin and subcutis between the claws with Fusobacterium necrophorum. The Fusobacterium can only enter the tissue through damaged skin, hence damage to the interdigital cleft caused by straw stubble or stony areas is a major risk factor. Wet conditions also soften the skin allowing damage to occur more easily. There is an increased incidence around calving suggesting that immunosuppression may increase the likelihood of infection.
- lameness, with claws forced apart by swelling of the skins between heels and accessory digits
- split in the interdigital skin, often with characteristic smell
- interdigital pus and necrotic tissue
- sometimes pyrexia (fever)
- systemic antibiotics - tylosin (eg Tylan 200 at 1ml/20kg intramuscular injection for 4 days)
- formalin footbaths