Foot rot is a common bacterial infection primarily affecting the hooves of livestock like sheep, goats, and cattle. This debilitating condition causes lameness, pain, and discomfort, significantly impacting animal welfare and productivity in agriculture. Effective management and control are important.
Defining Foot Rot
Foot rot is a contagious hoof infection caused by the synergistic action of specific anaerobic bacteria. The primary bacterial agents involved are Dichelobacter nodosus and Fusobacterium necrophorum. F. necrocrophorum often initiates the infection by causing inflammation of the interdigital skin, creating an entry point for D. nodosus. D. nodosus then produces enzymes that degrade the connective tissue between the hoof horn and the underlying sensitive tissues, leading to separation and decay.
These bacteria thrive in wet, warm, and unsanitary environments, which soften interdigital skin and promote bacterial growth. Injuries to the interdigital skin from rough surfaces or prolonged moisture also predispose animals to infection. While F. necrophorum can survive in soil for extended periods, D. nodosus persists for a shorter time in the environment but much longer in the hoof.
Identifying the Symptoms
Animals with foot rot typically display lameness, often the first observable sign. This can range from a slight limp to an inability to bear weight, sometimes causing them to graze on their knees. The skin between the toes may appear reddened, swollen, inflamed, and moist.
A characteristic foul odor often emanates from necrotic lesions between the claws. As the infection progresses, the hoof horn can separate from underlying soft tissues, starting at the heel and spreading across the sole and wall. In advanced cases, this underrunning of the hoof causes significant pain and reluctance to move, impacting feeding, weight gain, or milk production.
Treatment and Prevention Strategies
Treating foot rot involves a multi-faceted approach. Hoof trimming removes infected tissue, exposes bacteria to air, and facilitates topical treatment penetration. Foot bathing with solutions like 10-20% zinc sulfate or 5-10% copper sulfate disinfects hooves and controls bacterial spread. Zinc sulfate is preferred for sheep due to copper sensitivity.
For severe infections, systemic antibiotics like penicillin, oxytetracycline, or ceftiofur are administered, particularly when the disease has progressed into deeper hoof structures. Prompt treatment leads to rapid recovery. Beyond immediate treatment, prevention focuses on creating an environment less conducive to bacterial growth. Maintaining dry, clean animal living areas, especially around feed bunks and water sources, is important, as wet and muddy conditions promote infection.
Regular hoof inspection and trimming identify issues early, preventing injuries that allow bacterial entry. Quarantining new animals for several weeks before introduction prevents infected individuals from entering the main herd or flock. Strategic culling of chronically infected animals also reduces the infection source. Vaccines, such as Footvax for sheep and Fusogard for cattle, aim to reduce foot rot incidence and severity.