He points out that some stallions which have been shown at halter become very aggressive if they perceive they are being threatened or may be physically disciplined. They may have experienced some fairly strict physical discipline to get them mannered and trained to show properly. Use special care when handling these horses. He also warns that owners or handlers should not get between a stallion and another horse the stallion is interested in, regardless of the other horse's gender. When a stallion is being examined by a veterinarian, the handler should stay on the same side as the veterinarian and pay attention to the horse and its attitude, not to what the veterinarian is doing.
Stallions are easier to work on in a veterinary clinic or neutral site.
Some people, in an attempt to enhance either appearance or performance, may use anabolic steroids in either non-stallion halter or performance horses. According to Dr. Scoggins, anabolic steroids can increase a horse's aggressive, stallion-like behavior. These animals may be nearly as aggressive to handle as normal stallions and should be given the same respect. Although stallions are most aggressive during the spring and summer breeding season, they remain stallions all year round.