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 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, 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, with ad libitum feeding and high density diets.
  • 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: The disease can be observed with any kind of diet, but is more common in pelleted ones. It is believed that the pelleting process may have an effect on the fat present at the diet thus triggering digestive alterations in the large intestine.
  • It is more frequent in high energy + high protein diets (14,5 MJ DE/kg, 21% protein).
  • Some ingredients can also be associated.
  • It is frequent in diets where fat is used to keep the pellet together.
  • Continuous flow of animals predisposes them to the disease. 



Based on clinical signs and the elimination of other causes of diarrhea, particularly swine dysentery. It is necessary to perform a feces analysis together with a post mortem examination and laboratory analysis of an untreated pig presenting the typical symptoms. Porcine enteropathy may also be involved. 


  • Antibiotics administration might not always be successful because it depends on the presence of primary or secondary bacteria, but the following products used in the feed have given positive results in farms that present the problem.
    • Lincomycin
    • Monensine
    • Oxytetraciclyne
    • Salinomyicin
    • Tiamutin
    • Tylosine
  • To treat pigs individually, it might be helpful to inject them in a daily basis with tiamutin, lincomycin, tylosin or oxytetracycline.
  • The use of zinc in the diet must be considered, at a dosage of 2 to 3 kg/ton, because two weeks after the withdrawal of zinc used to prevent enteritis produced by E. coli at weaning, colitis may appear.

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