Rearing: shifting weight to hind legs and lifting both front legs, standing (1, 2)
Striking: kicking out with one or both front legs, often seen during rearing; may hear a squeal or snort during the strike (1)
Rearing and Striking can be seen at all ages, in the wild or domestically, in stallions, geldings, and mares, and in all breeds (1, 2). Rearing creates a vulnerable position for the horse's belly, exposing it to the threat, which is where the strike helps. It is most commonly seen between two stallions fighting over mares, but it can also be seen during play between friends or during a pain or stress event (1, 2, 3, 4).
Stall Housing and Restraint
Restraint and confinement can increase a horse's stress levels while providing no outlet for excess energy, so bringing them out for handling may trigger some unwanted behaviors like rearing and striking (3, 5).
Herd Dynamics
Rearing/Striking can be used between horses to establish a relationship to later decrease conflict and minimize aggression (1, 6, 7).
Rearing/Striking are also used between horses during play as a form of exercise and to practice fighting skills (1).
Social isolation can affect a horse's social development, leading to increased aggression and possibly rearing and striking (8).
Pain/Discomfort
Rearing/Striking could be a triggered fight response due to some kind of pain or stress (3, 4).
Ill-fitting tack can contribute to Rearing (3).
Stress
Increased stress levels could cause the horse to be on edge and close to being pushed past threshold, causing Rearing/Striking if it feels the need to defend itself (3, 4).
Training
As mentioned above, ill-fitting tack may contribute to Rearing frequency (3).
Stress in training may also trigger Rearing/Striking (3, 4).
Trauma
If a horse has gone through a traumatic event, it may hold onto it and think about that event when it is in similar situations later on (9, 10).
For example: If a saddle is pinching a horse's back, and a rider attempts to mount, causing the saddle to pinch more, the horse can rear from the pain. The memory of that event might trigger the horse to later rear during mounting, even with a fitted saddle.
Maximizing turnout will allow the horse to get its energy out spread out throughout the day, decreasing its need to "explode" on turnout.
Rearing and Striking are perfectly normal play behaviors, so allowing horses the opportunity to interact and play with others is essential.
Because Rearing and Striking can indicate pain or some kind of high stress, a vet or farrier might be able to locate the issue and recommend treatment.
Understanding Stress & LIMA
Rearing and Striking are reactions to some kind of trigger or stressor.
Learn to identify the smaller behaviors that lead up to Rearing, so you can preemptively calm the horse to prevent Rearing.
In the event of Rearing and Striking, release all pressure and give the horse time to decompress. Increasing pressure or punishing can escalate the situation and cause injury to you or the horse.
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