courtesy of OSU Extension
A successful breeding program depends on having a happy, healthy stallion who is willing to do his job. Good stallion managers have mastered the art of keeping their horses happy, confident and well behaved, which involves considering each horse as an individual.
Stallions are seasonal breeders, therefore longer daylight and warmer temperatures will begin the process of readying the stallion for breeding season. Stallions should enter the breeding season in optimal health and body condition. Ideally, the stallion enters the breeding season in a BCS (Body Condition Score) of 5 or 6 to help support his increased energy demands. While the act of breeding itself may not require a substantial amount of additional energy, stallions typically show more overall excitement and activity. Monitor weight throughout the season and adjust feed intake accordingly.
Another important consideration is the stallion’s soundness. Pain or discomfort can manifest itself in undesirable behaviors as the stallion experiences frustration between something that he finds desirable but elicits pain. If a stallion exhibits either aggressive behaviors or disinterest, it is important to first rule out pain, before starting any other behavioral management strategies.
Housing can also affect stallion behavior. Stallions are often housed and handled much differently than what they would experience in a natural setting. Stallions are often isolated from other horses to ensure the safety for them and other horses. Stallions kept in barns away from other horses may actually decrease libido in some cases. In nature, young stallions congregate together in bachelor bands, in contrast to the stallion with access to mares, known as the harem stallion. Stallions which are around only other stallions show decreased testicular size, thus, lower libido. This strategy allows them to live together with less conflict, but may adversely affect breeding stallions. Housing stallions around mares may help horses who are disinterested or reluctant breeders.

Some stallions may not show interest in mares due to their past handling. It is common in performance stallions to discourage or punish them from showing sexual interest during their careers. Stallions are often punished for “dropping” the penis or performing masturbation activities. While stallion managers may not have control over a horse’s past experiences, this practice should be discouraged in horses intended to be breeding stallions. Stallions should be allowed to exhibit normal breeding-related behaviors.
The mare used for breeding should also be considered for a stallion that is a reluctant breeder. While some stallions may do quite well with an ovariectomized mare (one with ovaries removed and provided synthetic estrogen) used for semen collection, most stallions do prefer a mare in natural estrus. A reluctant stallion may be more interested in a mare closer to ovulation versus early estrus. Allowing mares to exhibit the most natural behavior that is safely allowed will encourage a reluctant or novice breeder. For example, mares that are hobbled and twitched will not be able to show the same posture which shows acceptance to the stallion. Some stallions may even have color preferences in mares. Paying close attention to stallion preference can lead to success in the breeding shed.
Consider the breeding shed environment as well. Some stallions can be distracted by any extra noise or movement that may occur. If using a phantom or breeding dummy, check that it is firmly in place and does not rattle or make other sounds when mounting. Have only the required personnel present for safe handling of the mare and stallion. Extraneous people can be distracting for some stallions.
Selection and/or training of stallion and mare handlers is important. Sexual behavior in horses often can be intimidating to novice handlers, which can quickly lead to poor handling decisions. Overly timid behavior by the handler or excessive punishment for what is actually normal stallion behavior is likely to cause an increase in bad behavior. Vocalization, nipping and striking are all normal behavior for stallions. Good stallion handlers remain calm and do not overly punish or act punitively to punish the stallion for even adverse frustration behaviors.
The vast majority of stallions have learned to accept a variety of handling and breeding methods that may not mimic their natural breeding state. However, some stallions may show abnormal behaviors that may be either dangerous or otherwise unwanted.
In human-controlled horse reproduction, stallions may exhibit overly exuberant behavior such as charging, serious biting and rearing, which are not seen in natural breeding conditions. From the stallion’s perspective, hand breeding and artificial collection are far removed from natural breeding, where the mare’s receptivity guides his behavior. Simply put, mares would not tolerate such unacceptable behavior. In the stallion’s world, he is always right – as a trip to the shed means he will have the opportunity to breed. He may also have limited contact with mares on a day-to-day basis, and very little interaction with them before breeding. Coupled with overly harsh treatment, stallions can become conflicted by fear, while driven by a desire to breed.
Individuals who work with stallions should evaluate their own ability to safely handle them. If stallion handling causes fear, anxiety or anger in the handler, it may be best to seek qualified handling intervention. The best handlers do not let their emotions get involved and are able to separate a stallion’s breeding shed behavior from their day-to-day barn behavior.
Overall, remember that most poor stallion behavior is human induced. Systematically examine all handling procedures, and set fair and reasonable expectations for the stallion. Remember to pay attention to your stallion and what he needs for success. Normal sexual behavior should be allowed and provide the most predictable, comfortable routine possible. Most importantly, ask for professional help if needed.
