Atresia ani

Anal atresia is a congenital condition in which piglets are born without the outer hole of the rectum. These pigs have an abdomen that increases in size with age. The condition is difficult to repair and therefore these piglets must be euthanized.

Alternative names: Atresia of the anus, no anus, no rectum


Piglets are born with a blind rectum, 5-10 mm to the exterior and without anus. Do not try to repair it with surgery. The incidence in very old farms is usually below 0,5%. It is an inheritable condition, but of little incidence. The abdomens of the affected piglets increase in size and they usually die, although some survive several weeks after weaning. The affected pigs should be eutanized. Data collection may indicate whether any particular boar is involved. 




  • Distended abdomen.
  • Lack of feces.



Causes / Contributing Factors

  • Suspected genetic contribution.



The diagnosis is based on clinical visualization and visual confirmation of  lack of the anus.





Atlas of pathology

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