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


Groin Swelling in Mare or Gelding


In stallions swelling of the groin may relate to testicular conditions. Obviously, this is not a concern for mares or geldings.

As with any swelling, it is important to consider what anatomic structures exist in the area and which of them might be involved. In mares, this includes the mammary gland. Geldings occasionally develop sarcoids and other skin tumors in the groin area.

Abscesses occur in this area, but are difficult to diagnose without ultrasound. Puncture wounds to the area can cause infection and severe swelling and sometimes seal over quickly and thus might be hard to detect. Traumatic injury can result in hematoma or seroma formation here.

Complications from castration can persist chronically, or appear later. A hydrocele is a fluid accumulation within the remnants of the scrotal sac after castration.

  • Code Orange

    Call Your Vet at Their First Available Office Hours
    • If you feel the problem is severe or has come on suddenly.
    • 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.
  • Code Yellow

    Contact Your Vet at Your Convenience for an Appointment
    • If you consider this a chronic and relatively mild problem that is not changing rapidly.
    • If the results of the Whole Horse Exam (WHE) suggest the horse is otherwise normal.
You also might be observing
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your role


What To Do

Assess your horse's general health using the Whole Horse Exam (WHE), and feel the area carefully. Look for swelling both higher up on the abdominal wall and down the leg because swelling in other areas can spread to this area.

Gently press on the swelling and look for a pain response, but be careful not to be kicked. Does the swelling seem hard or soft? Is there moisture or drainage in the area? Carefully look under the rest of the belly for signs of hair loss or swelling. Is the horse lame at the walk or does the swelling appear to affect the horse's ability to move?

Contact your vet with your findings and concerns.

What Not To Do

Do not attempt to lance or open a swelling in this location! There are very large blood vessels in the groin region.

Do not attempt to assess the swollen area if it causes your horse undue stress or pain because you can easily get kicked.

your vet's role

Your vet will perform a physical exam and examine the affected area (often using ultrasound), in order to identify the underlying cause of the swelling.
Questions Your Vet Might Ask:
  • What is the horse's age, sex, breed and history?
  • Is the swelling getting better or worse?
  • How is the horse's attitude and appetite?
  • When did you first notice the swelling?
  • Do you notice any abnormalities of the penis or sheath?
  • Do you notice any swelling of the sheath?
  • Does the horse show any signs of lameness or resistance to move?
  • Does pressing on the area cause pain to the horse?
  • What does the swelling feel like?
  • 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