Yersinia infection

The Yersinia infection is usually subclinical although weaning piglets may have diarrhea.

Alternative names: Yersinia pseudotuberculosis, Yersinia enterocolitica


There are two species of this bacteria in the pig intestine, Yersinia pseudotuberculosis and Y. enterocolitica. They usually do not cause disease but they have been associated with small problems in weaned pigs.



  • It is not present.

Sucking piglets

  • It is rarely seen.

Nursery and fattening

  • Y. enterocolitica causes inflammation of the small and large intestine with diarrhea.
  • Y. pseudotuberculosis causes small abscesses along the tract.
  • Loss of appetite.
  • Mild fever.


Causes / Contributing Factors

This disease is transmitted through feces.



The main importance of this organism is that it produces a cross-reaction when blood tests for brucellosis are performed. It is likely that carrier pigs give a positive reaction. If this is the case, it is necessary to determine the point of infection during the growing period where the exposure is taking place and to break the cycle using management measures. Yersinia grows easily in the lab.



  • Systems all in / all out with cleaning and disinfection to reduce infection.
  • There is no effective treatment although antibiotics can reduce the rate of excretion.

Atlas of pathology

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