Foot rot

It is important to clarify that Dichelobacter nodosus is not a plant pathogen. It is a gram-negative, anaerobic bacterium that acts as the primary causative agent of foot rot, a severe infectious disease affecting the hooves of sheep, goats, and cattle. This condition is a significant welfare and economic issue in the livestock industry.

The pathogenesis of the disease involves the production of extracellular proteases by Dichelobacter nodosus, which digest the hoof horn and underlying tissues. While D. nodosus is the essential agent, other opportunistic bacteria, such as Fusobacterium necrophorum, often facilitate the initial invasion of the tissue.

The environmental survival of the bacteria is highly dependent on humidity and temperature. Warm, wet soil conditions allow the bacteria to persist outside the host for an extended period, facilitating transmission across the flock. Dry conditions typically limit the survival of the organism, slowing the spread of the infection.

Clinical symptoms range from mild interdigital dermatitis to severe separation of the hoof wall. Affected animals exhibit acute lameness, visible inflammation, and a characteristic foul-smelling discharge. The pain associated with the infection leads to reduced grazing, stunted growth, and decreased production of wool and milk.

• Regular hoof trimming and inspection
• Use of footbaths with zinc sulfate or copper sulfate
• Culling of chronically infected carriers
• Strategic pasture rotation
• Isolation and treatment of newly purchased livestock

Effective management requires a combination of strict biosecurity, environmental control, and systematic treatment protocols. Vaccination is also available in some regions to control the severity of outbreaks, although it must be combined with good husbandry practices to achieve long-term success.