| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| 3900-6 Acanthus | d.-bay | f | 2001 | Kris S | Alyssum | Thoroughbred | USA | |
| Acapella | bay | f | 2013 | Majestic Warrior | Kettle's Sister | Thoroughbred | USA | |
| Acarina | f | 1968 | Thoroughbred | Germany | ||||
| Acaroid | c | 1978 | Big Spruce | Thoroughbred | USA | |||
| Acatenango | chestnut | c | 1982 | Surumu | Aggravate | Thoroughbred | Germany | |
| Accada | f | Esclavo | Akita | Thoroughbred | ||||
| Accelerate | chestnut | c | 2013 | Lookin At Lucky | Issues | Thoroughbred | USA | |
| Accepted | br. | f | 1922 | Thoroughbred | Great Britain | |||
| Accessories | bay | f | 2003 | Singspiel | Anna Matrushka | Thoroughbred | Great Britain | |
| Accipiter | bay | c | 1971 | Damascus | Kingsland | Thoroughbred | USA |