Parasites and Diseases
Lumpy Jaw

A Field Guide


caption follows
Abscessed caribou lower jaw.

What causes lumpy jaw?
  • Lumpy jaw is caused by bacteria normally found in the mouths of healthy animals.
  • The bacteria can enter through wounds in the mouth, which can be caused by coarse feed or when teeth break through the gums during development.

Where does lumpy jaw occur?
  • Lumpy jaw can be found in ungulates such as sheep, caribou and moose throughout their range in Alaska.
  • The disease does not spread between animals.

What are the signs of lumpy jaw?
  • Infection of the jaw bone itself causes firm swellings that can be quite large.
  • Swellings containing thick yellow pus (abscesses) can also be found around the mouth and jaw.
  • Lumpy jaw may interfere with the animal’s ability to eat.
  • Other than the swelling on the jaw, animals may appear healthy.

How can I protect myself?
  • You cannot get lumpy jaw from infected animals.
  • Be careful not to cut into pus-filled swellings. If this happens, pus can be spread and contaminate other parts of the carcass.

Can I eat the meat?
  • Parts containing abscesses should not be eaten.
  • The remainder of the carcass is suitable for human consumption.

Samples to collect
  • Lower jaw and surrounding tissue
  • 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.