Polo is played with mares instead of horses, this in principle is because it has more advantages. In case the horse suffers an accident, the mare will be able to continue with her breeding life. On the other hand, there are some international specialists who assure that mares are more intelligent than males.
When we talk about high handicap polo, they have reproductive logistics where they use the best stallions with mares of great quality for this sport. Nowadays, in order to have the best quality horses, mares have started to be cloned, a clear example of this is Adolfo Cambiaso who is breeding exceptional horses.