Research from the University of California–Davis shows that 60 percent of cows successfully treated for foot warts, also known as digital dermatitis or hairy heel warts, have a recurrence of foot warts within seven to 15 weeks. The researchers cite these three risk factors:
Environment. Hairy heel warts are associated with wet, muddy conditions.
Bacteria. The scientists have isolated three types of Treponema bacteria in hooves infected with hairy heel warts. These are anaerobic bacteria, which is probably why hooves covered in mud and manure are more susceptible to foot warts — oxygen can’t reach the hoof, and moisture adds to the problem.
Management. Frequent alley scraping and other facility and manure management techniques can help control foot warts by reducing favorable growth conditions. Proper use of footbaths helps, too, just be aware of other environmental issues associated with products like copper sulfate.
So, focus on these key areas if you want to keep foot warts from coming back. Reduce the prevalence in your herd.