Colitis is an infection of the large intestine mainly in pigs from 6 to 14 weeks of age. This is characterized by diarrhea without blood and with few or no mucus.

Alternative names: Spirochaetal colitis, porcine intestinal spirochaetosis, non-dysenteric colitis, Brachyspira pilosicoli


"Colitis" means large intestine inflammation. In some countries it is common in growing pigs and is characterized by diarrhea. It is not frequent in pigs fed with feed prepared in the farm. The clinical presentation is similar to swine dysentery except that is much milder.

The affected pigs are 6 to 14 weeks of age, and the disease can affect 50% of the group. It is not observed in lactating sows or adult animals. However it can be individually seen in sows. Several organisms are associated with colitis (weakly beta-hemolytic Brachyspira spp), but Brachyspira pilosicoli, an organism similar to the one causing porcine dysentery, is important. 



Sows and lactating piglets

  • No symptoms.

Weaners and growers

  • Symptoms commonly appear in fast growing pigs, from 6 to 14 weeks of age.
  • First symptoms:
    • Loose feces that look like cow’s manure, without blood and almost no mucus.
    • Pigs with normal behavior.
  • When the disease gets more serious:
    • Watery diarrhea
    • Dehydration.
    • Loss of body condition.
    • Poor growth.


Causes / Contributing Factors

  • Diet factors:
    • More common in pelleted diets.
    • Diets with high levels of soluble non-starch polysaccharide (“soluble fiber”) in grains (barley and rye).
  • Continuous flow of animals predisposes them to the disease.
  • Reservoir hosts in wild birds and rodents.



  • Clinical signs.
  • Post mortem exam with lesions restricted to colon.
  • Histochemistry with silver staining or FISH.
  • Culture.
  • PCR.
  • Rule out swine dysentery and ileitis.


  • Antibiotics administration might not always be successful.
  • The use of zinc in the diet must be considered.
  • Rodent and wild bird control.
  • All-in-all-out pig flow.

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