Animal HealthDiseasesFoot and Mouth DiseaseSigns and Symptoms

Foot and Mouth Disease (FMD) Signs and Symptoms

A list of clinical signs the animal may or may not display.

Blisters followed by erosions in the mouth or on the feet and the resulting slobbering or lameness are the best known signs of the disease. Blisters may not be observed because they easily rupture, leading to erosions.

Some of these other signs may appear in affected animals during an FMD outbreak:

  • Temperatures rise markedly, then usually fall in 2-3 days
  • Ruptured blisters discharge clear or cloudy fluid, leave raw areas surrounded by ragged fragments of loose tissue
  • Sticky, foamy, stringy saliva is produced
  • Consumption of feed is reduced because of painful tongue and mouth lesions
  • Lameness with reluctance to move is often observed
  • Abortions often occur, and conception rates may be low
  • Milk flow of infected cows drops abruptly
  • FMD can lead to myocarditis (inflammation of muscular walls of the heart) and death, especially in newborn animals. Animals do not normally regain lost weight for many months. Recovered cows seldom produce milk at their former rates.

Animal Health Bureau

Helpful Links


Contact Information

Department of Livestock
Animal Health Bureau
PO Box 202001
Helena, MT 59620-2001
Email Us