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Observation
What you see. The starting point for addressing any equine health related issue is your observation.

YOU ARE OBSERVING

Tissue Protruding from Anus or Rectum

Summary

It is not uncommon after a horse defecates for a small ring of red rectal lining tissue to evert from the anus for a second after manure is passed, but then almost immediately disappear. It is abnormal for this to persist any longer than a second after the fecal ball is passed. If this sign is particularly prevalent in a horse, it could indicate that the manure is especially fibrous or dry and it might warrant an assessment by your vet.

Horses that strain to defecate for prolonged periods may force rectal tissue out through the anus. Severe abdominal pushing and straining can occur as a response to chronic diarrhea, constipation, and especially after prolonged labor (dystocia). This turning inside out (eversion) of the rectal tissue is known as rectal prolapse. Prolapsed tissue quickly becomes a swollen and will look like a firm red ball. Severe rectal prolapse of large amounts of tissue (more than a softball size) can be fatal.

Any persistent mass of tissue at the anus will require veterinary care to resolve. In rare cases, a red mass at the anus is a tumor, abscess or other condition.

When dealing with mares, keep in mind that tissue can also protrude from the vagina (usually in pregnant mares or those that have just foaled), so be sure that you know which orifice the tissue is coming from.

Gruesome aside: Rectal prolapse in a dead horse is also not uncommon. Dead horses bloat and the pressure inside the belly forces the rectum to turn inside out. The presence of this finding does not say much about the cause of death, although horses with intestinal obstruction may bloat more.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
    • If there is persistent abnormal tissue visible at the anus.
  • Code Green

    Contact Your Vet to Obtain Useful Advice & Resources
    • Tissue disappears immediately after defecation.
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your role

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What To Do

Call your vet immediately. If this is a rectal prolapse, the longer the tissue protrudes, the more swelling develops and the more tissue damage occurs. If you were forced to manage a rectal prolapse yourself, start by keeping the horse as calm as possible. With a helper holding the head of the horse, you can try to keep the tissue moist with a wet towel until your vet is able to examine the horse. Be careful not to be kicked. You may be able to begin to shrink the swollen tissues by applying sugar to the tissues, wrapping the mass in the wet towel, and gently compressing the tissues with the flat of your hand over the towel. However, only do any of this if your vet agrees it is indicated or you are not able to secure veterinary assistance.

What Not To Do

Do not mistake rectal prolapse with a prolapse of the vagina or uterus in a mare. That said, all are veterinary emergencies.

Do not attempt to replace the tissue yourself, without vet guidance. It is easy to perforate the tissue, potentially causing severe complications.

Do not assume that because a dead horse has protruding tissue from the anus, that this was the cause of death. This is a fairly common post-mortem finding.

your vet's role

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Your vet evaluates the tissue protruding from the anus, and determines the nature of the tissue and it's cause. Part of this evaluation is an assessment of the horse's general health. For momentary eversion of rectal lining, either no treatment is necessary, or your vet may advise feed or management change to change consistency of manure. For a persistent mass: Once the nature of the problem is determined, treatments can be considered. If this is rectal prolapse, vets often use sedation and sometimes spinal epidural anesthesia to facilitate replacing the rectal tissue. The factors that caused the prolapse will need to be considered and managed too.
Questions Your Vet Might Ask:
  • What is the horse's age, sex, breed and history?
  • When did you first notice this?
  • How is the horse's attitude and appetite?
  • What is the color and appearance of the mass?
  • What is the size, shape and feel of the mass?
  • Have you noticed that the horse has had diarrhea?
  • Is this a mare that has just had a difficult foaling (dystocia)?
  • What are the results of the Whole Horse Exam (WHE)?

Author: Doug Thal DVM Dipl. ABVP