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


Vaginal or Vulvar Discharge (White, Yellow or Reddish) Non-Pregnant Mare


White or yellow vaginal discharge in a non-pregnant mare can be a sign of uterine or vaginal infection, or inflammation from a variety of causes. White or cloudy semen-containing discharge may be present shortly after breeding, which is normal. Mares in heat (estrus) often have a clear or mucous discharge.

Reddish discharge in a mare that recently foaled or aborted is considered normal for at least 7 days post-foaling. However, a post-foaling mare should always be bright and have a good appetite. After foaling, longer term white or yellow discharge could indicate an infection or chronic inflammation.

Keep in mind that mare urine often contains whitish green crystals that can accumulate as a whitish paste on the vulvar lips and be confused with vaginal discharge.

  • Code Orange

    Call Your Vet at Their First Available Office 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.
    • Any colored vaginal discharge should prompt an examination by your vet.
  • Code Green

    Contact Your Vet to Obtain Useful Advice & Resources
    • If the results of the Whole Horse Exam (WHE) suggest the horse is otherwise normal.
    • If the mare has a reddish discharge for up to 10 days after foaling.

your role


What To Do

Assess your mare's general health using the Whole Horse Exam (WHE) and consider this observation within the context of the scenarios described above.

If your mare is showing any other sign of illness (especially a fever), or if she is presumed pregnant, contact your vet immediately to discuss your findings and concerns.

your vet's role

The approach your vet takes depends on the mare's reproductive history. If your vet is concerned about infection or inflammation then rectal palpation, ultrasound, and other uterine diagnostics are used to determine the diagnosis, best treatment plan, and prognosis.
Questions Your Vet Might Ask:
  • Did the mare recently foal?
  • Are you trying to breed the mare?
  • How old is the mare?
  • What is the color and quantity of the discharge?
  • To your knowledge, is the mare pregnant?
  • Does the discharge have a noticeable odor?
  • When did the mare have her last foal?

Diagnoses Your Vet May Consider

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

Very Common
Less Common
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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)

Very Common
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Author: Doug Thal DVM Dipl. ABVP