Many people incorrectly think that Miniature Horses and the Falabella breed are actually dwarf horses, which is false. Miniature horses and Falabellas are bred to be small and through selective breeding have developed into their own breeds that breed true to small, usually well-conformed horses. However, it is true that dwarf horses have been used in the development of the Miniature Horses bred by disreputable breeders resulting in a greater likelihood of dwarf offspring from Miniature Horses. This short cut to developing the smallest possible Miniature Horses has had disastrous results. Falabella horses, only being bred by one family, have had fewer problems with dwarfism as the breeding herd was comprehensively managed. Full sized or "normal sized" horses of any breed will very rarely produce a dwarf offspring, but this is extremely uncommon. Some pony breeds, especially in remote areas of the world where the breeds have been very isolated and have inbred continually, dwarfism is a serious concern to the continuation of the breed.
Dwarfism is caused by a genetic malfunction or degeneration of the genetic make-up of the foal that is inherited from either the dam or the sire. There are actually 320 different types of dwarfism that have been identified in horses and these can be mild and almost unobservable, but will often result in health problems or internal malformations. The dwarfism that is most obvious may range from a mild distortion of the physical appearance of the horse through to horrible deformations that cannot be treated or corrected. Dwarf horses should not be bred and many will be infertile or unable to reproduce due to malformations of the reproductive system.
Brachiocephalia is a dwarf condition that is characterized by a very small body with a disproportionately large malformed head. Typically there are limb disfigurements as well, usually short, very stocky and bent legs are present. Often these horses have pushed in faces that restrict the horse's ability to breath, graze or chew. Many of the brachiocephalic foals are destroyed at birth as the deformations are too severe to be corrected surgically or to allow the foal to live a normal life. In mild cases the nostrils can be enlarged surgically and reconstructive operations can be performed if needed to allow breathing and eating.
Diastrophia is a dwarfism that results in twisted and deformed limbs with skeletal malformation of the spine. Usually these dwarfs will have an arched back and mild to moderately deformed limbs, some which can be corrected with shoes and surgical procedures.
Achondroplastic dwarfisms is the least problematic for most horses and results in very short legs with a normal sized body and head. Often the ears of these dwarf horses are also very small, but overall these horses are healthy and can live a normal life.
Although dwarfism often results in deformations, not all are serious or debilitating to the horse. There are dwarf horses adoption centers and rescues across North America to care for both miniatures and dwarf horses that are always looking for loving homes for these wonderful animals. If you are interested in adopting a dwarf or miniature horse contact the rescue in your area.