Lameness: Heel Warts
Dairy Cattle Disease

Disease description: digital dermatitis (heel warts)

Digital dermatitis, also called heel warts or hairy foot warts, is one of the leading causes of lameness in dairy cattle. Lesions, which usually occur just above the heels on the rear feet, develop finger-like projections and are extremely painful to the animal. Treponema spp., which are invasive corkscrew-shaped bacteria, are the primary cause of disease. They colonize the outer layers of non-living skin and invade living tissue.

The disease is spread easily among animals, especially where there is overcrowding, poor drainage, accumulation of manure and urine on floors, rough flooring, or dirty, wet or uncomfortable bedding areas. The constant exposure of animals to the invasive bacteria makes this disease very difficult to manage.

High-risk animals include cows in early lactation and replacement heifers from off-premises.

Disease costs

Each case of hairy heel warts costs producers $150 or more, due to:

• Lower milk production
• Premature culling
• Extra days open
• Antibiotic and hoof wrapping expenses

Clinical signs

Lesions most commonly occur on the rear feet (less commonly on front feet), just above the heels, and are the primary clinical sign. Reduced milk production and difficulty walking can also be observed.

Disease prevention

In the past, to reduce the incidence of digital dermatitis in their herds, producers have used chemicals like formaldehyde and copper sulfate as well as antibiotics like tetracycline in footbaths. These chemicals and antibiotics can represent significant environmental, worker safety and milk quality hazards.