Cause: Blood smeared on the sides of pigs is often an indication that there is a pig with a prolapsed rectum in that pen. A prolapsed rectum occurs because excessive abdominal pressure pushes the rectum out through the anus. This can be due to coughing, diarrhea and straining, or cold weather that makes pigs pile on top of each other. Rectal prolapses may also occur in pigs whose tails have been cut too short causing damage to the nerve supply to the anus. If the anus lacks a good nerve supply it relaxes and may allow the rectum to protrude when the pig defecates. Baby pigs should only have two-thirds of their tails removed.
Treatment: Occasionally a small prolapse will spontaneously return to its normal place, but usually when a prolapse is observed it will remain outside the pig. A prolapse the size of the one shown in the image on your screen definitely will not return to normal on its own. A pig with a rectal prolapse should be moved to the hospital pen to protect it from pen mates that will chew on the protruding tissue. The pig should be given a unique ear tag that immediately identifies it as a prolapse pig and be injected with procaine penicillin at recommended treatment rates. When left alone, the protruding rectal tissue will eventually dry up and fall off.