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This is caused by the bacteria, Actinobacillus suis and Actinobacillus equuli. The first of these is present in most herds and lives in the tonsils of older pigs, particularly sows. It usually only affects piglets.


  • Rarely applicable.
  • Sudden death.
  • Discoloration of skin (blue).
  • High fever.
  • Coughing.
  • Pneumonia.
  • Skin lesions (not to be confused with Erysipelas).
  • Arthritis.
  • Lameness.
  • Septicaemia.
Weaners & Growers
  • Rarely seen.
  • Symptoms as for piglets

Causes / Contributing factors

  • It can be precipitated by PRRS.
  • Teeth clipping .
  • De-tailing.
  • Scrubbed knees.
  • It may enter the piglet via the respiratory system or via cuts and abrasions.
  • It occasionally multiplies in the blood stream and settles out in various parts of the body, particularly the lungs and the joints. Here it produces multiple small abscesses.


Post-mortem and laboratory examinations to demonstrate characteristic lesions and the presence of the organism. It has to be differentiated from meningitis, acute E. coli infection, erysipelas, clostridial diseases and piglets that have been laid on.

Further Reading

Click on the links below to find out more about this disease, including treatment, management control and prevention information. The top link is the main article on this disease.