| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Action Francaise | d.-bay | f | 1985 | Nureyev | Allez France | Thoroughbred | USA | |
| Action Music | d.-bay | f | 1993 | Seattle Song | Abloom | Thoroughbred | USA | |
| Action This Day | bay | c | 2001 | Kris S | Najecam | Thoroughbred | USA | |
| Actium | bay | f | 1893 | Abonnent | Thoroughbred | Austria | ||
| Activar | bay | f | 1981 | Naskra | Speed On | Thoroughbred | USA | |
| Activate | bay | f | 1946 | Thoroughbred | Great Britain | |||
| 2774-5 Active Lemon | chestnut | f | 2006 | 643094100000822 | Lemon Drop Kid | Autumn Creek | Thoroughbred | USA |
| Active Voice | bay | f | 1977 | Pretense | Mellow Marsh | Thoroughbred | USA | |
| Ad | chestnut | c | 1979 | 3018 Dar | 3214 Afrodita | Thoroughbred | Voskhod Stud | |
| Ad Altiora | grey | f | 1953 | Labrador | Ultima Ratio | Thoroughbred | France |