Foot rot is an infectious condition that causes swelling, heat and inflammation in cattle’s feet, resulting in severe lameness. Swelling and lameness can appear suddenly, with the animal walking normally one day but limping the next day. Lame cattle can lose weight quickly if they’re reluctant to travel to feed and water.

J. Dustin Loy, veterinary diagnostic microbiologist in the University of Nebraska’s Veterinary Diagnostic Center, says the microbes associated with foot rot are mainly anaerobes, meaning they thrive in an environment without oxygen.

“The most common is Fusobacterium necrophorum. We usually find one or more of several other anaerobic bacteria associated with it, including Prevotella and Porphyromonas. They’re all gram-negative anaerobes. We often find one that used to be called Arcano-bacterium pyogenes and is now called Truperella pyogenes. It forms pus and helps induce the anaerobic environment for other bacteria by reducing oxygen in the tissues,” he explains.

Andrew Niehaus, Ohio State University College of Veterinary Medicine, says the anaerobic bacteria are symbiotic. “One of them enters the break in the skin, and another comes along and helps perpetuate the infection,” he says. The bacteria multiply and further damage and destroy tissue, which leads to more anaerobic conditions as the tissue dies, which further facilitates the infection.

Many of these bacteria are normally found in feces. “The animals are always exposed to them, so there must be a predisposing factor such as a break in the skin — in the space between the toes,” Loy adds.

Once bacteria are introduced, it takes about a week for the bacteria to set up the anaerobic conditions needed to multiply rapidly and secrete toxins that cause tissue damage. Then the animal goes suddenly lame. The pain and lameness are due to immune responses that create inflammation and swelling.

Matt Miesner, clinical associate and a professor in Kansas State University’s College of Veterinary Medicine, says it’s hard to know why incidence varies from one year to the next. Perhaps it’s a variation in the pathogenicity of the strain of bacteria, but it may involve environmental factors.

“Maybe we had a wet spell and the feet become soft and more easily damaged. It doesn’t take much of an opening for bacteria to get started,” Miesner says. Just walking on gravel or sharp ice can create nicks and abrasions.

“Once you get a few cases, bacteria may be spread from draining lesions, putting a higher concentration in the environment. Once you have it, this tends to amplify it,” he says.

Kathryn Bach, a Colorado State University livestock intern, says foot rot may occur more frequently after a period of rain. “Cattle may congregate under shade trees where they defecate or urinate and their feet are wet,” she says. When tissue between the toes is softened by moisture or damaged by acid in manure, it’s more easily scraped or punctured.

foot rot in cattle