Mycoplasma suis

Mycoplasma suis causes anemia and agalactia in swine. Formerly referred as Eperythrozoonosis disease.

Alternative names: Eperythrozoonosis, Eperythrozoon suis, Mycoplasma suis, Mycoplasma suis


Mycoplasma suis is a mycoplasma that infects erythrocytes causing anemia. Previously this disease was called Eperythrozoonosis and was thought to be caused by a rickettsia called Eperythrozoon suis adhering to erythrocytes. Thanks to technical advances, this organism has been reclassified as a mycoplasma. Clinical disease is more commonly seen in lactating and growing pigs, but can also cause reproductive problems. This organism is capable of crossing the placenta and be responsible for the birth of weak and pale piglets and a high pre-weaning mortality. It is widespread and can be detected in both healthy and diseased animals.


Acute disease:

  • Anorexia
  • Fever of 40-42 ° C.
  • Anemia.
  • Increased breathing.
  • Anestrus.
  • Pale skin (jaundice).
  • Agalactia.
  • Abortion.
  • Increased returns.
  • Reduction of conception rate.
  • Reproductive failure.

Lactating piglets:

  • In severe cases it can cause jaundice.
  • Secondary infections tend to occur.
  • More chronic cases that result in slow growth and pigs that do not thrive.
  • Pigs are pale and anemic.

Nursery and fattening:

  • Anemia.
  • Pale pigs (jaundice).
  • Low or variable growth.
  • Pigs are in bad condition, wasted, hairy.

Causes / Contributing Factors

  • Biting insects
  • Internal parasites.
  • Lice or scabies.
  • Cannibalism / Vices (abnormal behavior).
  • Vaccination of several sows with the same needle.
  • When performing tail docking, teeth clipping and when giving iron injections to the piglets.


  • PCR.
  • Blood smear with Wright dye (not as accurate as PCR).
  • The presence of the organism does not confirm the clinical diagnosis.
  • Serological tests have so far been unreliable although improving.


Consider the following treatments and consult your veterinarian:

  • Tetracyclines and organic arsenicals have been used with success.
  • Some organisms are intracellular making them difficult to treat.
  • Disinfect piglets’ processing equipment.
  • Frequent change of needles for vaccination or injections.

Atlas of pathology

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