Digital Dermatitis (Mortellaro's Disease): Comprehensive Welfare Guide

Key Facts

• Digital dermatitis affects 70-80% of dairy herds globally and is the single most common cause of cattle lameness
• Active lesions (M2 stage) are intensely painful strawberry-like ulcers at the skin-hoof junction
• The bacteria form deep biofilms that make complete eradication from a herd very difficult
• Oxytetracycline spray applied to clean, dry lesions has good efficacy in early stages
• Foot bathing 2-4 times per week with formalin, copper sulfate, or lincomycin controls but does not eradicate the disease

Welfare Considerations

Digital dermatitis causes immense global welfare suffering — with 70-80% of dairy herds affected and multiple cows per herd showing active lesions at any time, the total pain burden is extraordinary. Active M2 lesions are acutely painful: cows lift their feet, are reluctant to walk, and show obvious lameness scoring 2-3 on a 5-point scale. Welfare-centered management requires prompt identification of active lesions through regular foot inspection, immediate topical treatment, and follow-up to confirm healing. Farms with high DD prevalence must review their hoof bathing frequency and hyperkeratosis trimming protocols, as these provide the substrate for Treponema entry.

What You Can Do

• Implement regular foot inspection — ideally monthly — to detect and treat active M2 lesions promptly
• Apply oxytetracycline spray to all active lesions after cleaning and drying the foot
• Use foot bathing 2-4 times per week as standard disease management — increase frequency during high incidence periods
• Record all lameness events with DD stage coding to track herd prevalence over time
• Consult a hoof health vet to develop a digital dermatitis action plan targeting a herd prevalence below 10%