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


Manure has Blood in It, or Bleeding from Anus


Blood in a horse's manure can be a sign of many conditions. Bright red blood or blood clots often originate in the rectum or anus, and are most likely caused by a bleeding tumor or mass within the anal canal, rectum or lower colon.

Rectal tears caused by veterinary rectal palpation or other traumatic injury can also cause this type of bleeding. Horses could have blood in their manure after colic surgery if the intestine is surgically opened and there has been some bleeding into the intestine.

Manure containing dark red (almost black) blood generally means that the blood originates upstream in the intestine. Horses with clotting problems can bleed into their intestine, and this appears as dark or light red blood in the manure.

  • Code Red

    Call Your Vet Immediately, Even Outside Business Hours
    • If the results of the Whole Horse Exam (WHE) in the resting horse indicate fever (Temp>101F/38.3C), or heart rate greater than 48 BPM.
You also might be observing
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your role


What To Do

If you see blood in your horse's manure or coming out from their anus, assess the horse's general health using the Whole Horse Exam (WHE), and contact your vet with your findings and concerns.

your vet's role

Your vet rules out conditions that could cause this sign. That usually starts with a general physical exam to assess body-wide health. In some cases, we look for trace amounts of blood in the manure using special sensitive tests to identify blood components.
Questions Your Vet Might Ask:
  • Has the mare recently been bred or has she foaled?
  • Has anyone recently taken your horse's temperature?
  • Has the horse had colic surgery recently?
  • How is the horse's attitude and appetite?
  • Has the horse had a rectal palpation by a vet recently?
  • Do you notice melanomas around the anus?
  • Is the horse gray?
  • What are the results of the Whole Horse Exam (WHE)?

Diagnoses Your Vet May Consider

The cause of the problem. These are conditions or ailments that are the cause of the observations you make.

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Treatments Your Vet May Recommend

A way to resolve the condition or diagnosis. Resolving the underlying cause or treating the signs of disease (symptomatic treatment)

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Author: Doug Thal DVM Dipl. ABVP