Parasites and Diseases

A Field Guide


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Swollen caribou hoof with hoofrot.

What causes hoofrot?
  • This disease is caused by the bacterium known as Spherophorous necrophorous.
  • This bacterium is a normal inhabitant of the soil. It can also be found in the mouth and intestinal tract of many species of animals.
  • The bacteria often enter a susceptible host through a break in the skin directly above the hoof.

Where does hoofrot occur?
  • Caribou and reindeer are the most common hosts of hoofrot infection.
  • This disease can occur in any caribou herd. During the late 1990s, it was observed in the Mulchatna and Western Arctic herds.
  • Outbreaks of disease are most common and most severe during periods of extended rainy weather.

What are the signs of hoofrot?
  • Abscesses form directly above the hoof. The hoof may swell 2 – 3 times its normal size. The abscess contains thick, foul-smelling pus.
  • Infected caribou often limp.
  • Abscesses may also be found in other locations, such as the liver, lungs or mouth.

How can I protect myself?
  • People are theoretically susceptible to infection. However, there have never been any human cases of this disease reported in Alaska.
  • Humans should avoid direct contact with pus-filled abscesses.
  • If possible, wear rubber gloves when butchering a caribou with abscesses on the hooves.

Can I eat the meat? [cook well]
  • The meat of caribou with hoofrot is safe to eat.
  • Discard the infected leg. Cook the remainder of the meat thoroughly.

Samples to collect
  • Remove the lower leg at the first joint. Place it in a plastic bag and keep cool.
  • To report an occurrence or to submit a sample for identification/analysis, contact the DWC Wildlife Disease Surveillance reporting hotline 907-328-8354, send an email to or visit your local ADF&G office.