Typically, undesirable behaviors in horses refer to those that an owner or handler finds irritating, destructive, damaging, unsafe towards humans, or a health or safety risk to the animal. Treating undesirable behaviors can be tricky, especially because not all undesirable behaviors are abnormal for horses.

Examples of undesirable behaviors in horses include:

• Pawing and striking;
• Rearing and bucking;
• Bolting or shying;
• Refusing to move;
• Biting or bite threats;
• Stereotypies (repetitive behaviors that appear to have no purpose); and
• Self-injurious behaviors.

“These behaviors can be exhibited due to underlying pain, fear, fear of pain, anxiety, frustration, conflict, confusion, underlying untreated medical conditions, inappropriate management, and even poorly applied training and handling,” said Sharon Carroll, MS, of the University of Queensland’s School of Veterinary Science, in Australia.

Undesirable behaviors put both horses and handlers or riders at risk of injury, pose welfare issues, and contribute to wastage in (horses exiting) the equine industry, said Carroll, who with colleagues recently published a review study on the subject.

“Many behaviors that owners find concerning are actually normal responses; however, they may still need to be modified to improve human and horse safety and reduce the rates of relinquishment, rehoming, or euthanasia,” said Carroll.

Often, behaviors that are normal are viewed as undesirable because horses are large animals with quick reactions and neophobic (irrational dislike of the unfamiliar) and claustrophobic tendencies, she added. “Their natural traits can be at odds with common human expectations for compliance in a range of settings, including confined areas, and highly stimulating environments.”

One of the major contributors to behavior problems in horses is pain. Carroll said pain should always be investigated as a potential cause of undesirable behavior, especially if the behavior has a sudden onset. Once the horse is no longer experiencing pain, the behaviors might immediately diminish or can be eliminated through the implementation of a targeted behavior modification plan.

Behavior modification strategies include reinforcing desirable behaviors by either adding a pleasant stimulus after the desired behavior or removing an aversive stimulus in response to the horse performing the desired behavior. Behaviorists refer to these as positive and negative reinforcement, respectively.

In most instances behaviorists consider reinforcement of desirable behaviors preferable to punishing undesirable behaviors, she said.

“When behaviors are punished, the goal is for the horse to experience pain, discomfort, or an unpleasant consequence after performing an undesirable behavior,” Carroll explained. “In contrast, reinforcement provides a pleasant consequence after performing desirable behaviors. Focusing on creating more of the desirable behaviors allows the undesirable behaviors to be replaced with a more desirable alternative.”

Although both positive punishment and negative reinforcement involve applying an aversive stimulus, handlers typically apply positive punishment to horses with no warning.

“This can induce fear and anxiety and, commonly, the severity of the aversive also causes pain,” said Carroll. “The aversive stimulus used in negative reinforcement (such as use of a whip) is applied ahead of the behavior and does not need to be applied rapidly or with any severity. There is no need for fear or pain, only enough pressure to induce the desired behavior and then the aversive stimulus is immediately removed, thus reinforcing the behavior.”

Carroll emphasized that in many cases, the undesirable—but not abnormal—behaviors might need modification to not only improve human safety but also strengthen the horse-human bond.

“Behavior issues can best be addressed by treating physiologic issues such as pain, altering the horse’s handling/training/management, and, where needed, undertaking more targeted behavior-modifying training,” said Carroll.

The study, “Understanding and treating equine behavioural problems,” was published in the June-July edition of Veterinary Journal.