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


Irritability, Moodiness, or Aggression Toward People


These sorts of behavioral problem are unfortunately quite common, especially in intensively stabled horses. Irritable behavior includes ear pinning, teeth grinding, head shaking, attempting to lunge toward a handler, trying to bite, and many others. More extreme behaviors include actual biting and kicking.

Genetics, and current and past handling (horsemanship) are the biggest contributors to a horse's attitude. Undetected chronic pain, low grade illness, poor handling, limited turnout, high carbohydrate feeding, and intense show and training schedules - any single one of these or combination also can contribute to this and other behavioral problems.

Taken alone, this observation is usually too broad a sign to help your vet narrow down the problem. However, this behavior is often accompanied by other abnormalities that, taken together, assist your vet in choosing appropriate diagnostics, reaching a diagnosis, and suggesting treatment options. By being an astute observer of your horse, you may notice additional signs that help determine the need for veterinary intervention.

  • Code Orange

    Call Your Vet at Their First Available Office Hours
    • If you feel the problem is severe or has come on suddenly.
  • 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.
You also might be observing
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your role


What To Do

If you notice that your horse is irritable, moody or aggressive that is a good starting point for additional observation. Take some time to carefully watch your horse and assess their environment for any other problems.

Notice when this behavior occurs. Does this behavior arise at a particular time or during a particular activity? What attempts have you made to resolve this behavior, if any? Assess your horse's general health using the Whole Horse Exam (WHE), looking for any abnormalities.

Share your findings and concerns with your vet.

What Not To Do

Do not take chances handling the horse if you are not confident in doing so.

Skills you may need

Procedures that you may need to perform on your horse.

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your vet's role

Your vet will seek to rule out pain-causing and physical disorders, and may make management or dietary recommendations. Then, efforts can be made in behavioral modification.
Questions Your Vet Might Ask:
  • When did you last notice the horse behaving normally?
  • How is the horse managed?
  • Do you notice other behavioral changes?
  • Is the behavior associated with handling?
  • Is the horse eating, drinking and behaving normally otherwise?
  • How is the horse fed?
  • What are the results of the Whole Horse Exam (WHE)?

Diagnostics Your Vet May Perform

Figuring out the cause of the problem. These are tests or procedures used by your vet to determine what’s wrong.

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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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further reading & resources

Author: Doug Thal DVM Dipl. ABVP