| Equid | Horse Name ▲ | Breed | Age | Gender | Color | Discipline | Owner |
|---|---|---|---|---|---|---|---|
| 273818C | Ophiuchus | Quarab | SY16 (11yo) | Stallion | Bay Tobiano | TC | Rhianon |
| 054518B | Oppositional | Irish Sport Horse | SY18 (9yo) | Mare | Palomino | EV | Rhianon |
| 122712C | Optical Illusion | Thoroughbred | SY12 (15yo) | Stallion | Silver Perlino Overo | JP | Lissa |
| 058316S | Optimus Primo | Lusitano | SY16 (11yo) | Stallion | Classic Champagne | WE | Manders |
| 166111C | Opulence | Arabian Pony | SY11 (16yo) | Mare | Chestnut | EV | Lissa |
| 498424B | Oracle SW | Holsteiner | SY24 (3yo) | Mare | Chestnut | EV | Shanny |
| 155618C | Oraculo | Lusitano | SY18 (9yo) | Stallion | Grulla | WE | Merry |
| 205722C | Orange Odyssey | Quarter Horse | SY22 (5yo) | Stallion | Chestnut | SR | Jewel |
| 125413C | Orange U Glad I Didnt Say Banana | Knabstrupper | SY13 (14yo) | Mare | Palomino Leopard | EV | Jen |
| 331521B | Orbital | Thoroughbred | SY21 (6yo) | Mare | Grey | CC | Rhianon |
| 270622B | Oregon Optics | Thoroughbred | SY22 (5yo) | Mare | Grey Overo | FR | Lissa |
| 148013C | Oregon Trail | Thoroughbred | SY13 (14yo) | Mare | Palomino | CC | Lissa |
| 472518S | Orgullo | Lusitano | SY18 (9yo) | Stallion | Grey | WE | Merry |
| 327119C | Oriol | Hispano Arabe | SY19 (8yo) | Stallion | Grey | WE | Athene |
| 273417C | Orion | Morab | SY17 (10yo) | Stallion | Chestnut | TC | Rhianon |
| 313322C | Orpheus | Thoroughbred | SY22 (5yo) | Stallion | Smoky Cream | EV | Morrigan |
| 483817C | Oskar | Arabian | SY17 (10yo) | Stallion | Grey | EN | Lorelei |
| 165119C | Osmosis | Connemara | SY19 (8yo) | Stallion | Palomino | DG | Lissa |
| 155518C | Ostara | Lusitano | SY18 (9yo) | Mare | Grey | WE | Merry |
| 145520B | Ouija SW | Danish Warmblood | SY20 (7yo) | Mare | Black | CC | Shanny |
| 314321C | Ourense | Andalusian | SY21 (6yo) | Stallion | Black Pearl | WE | Athene |
| 472818S | Ouro | Lusitano | SY18 (9yo) | Mare | Palomino | WE | Merry |
| 108820B | Out Of Order | Thoroughbred | SY20 (7yo) | Mare | Grey Sabino | FR | Lissa |
| 141921C | Outback Legend | Thoroughbred | SY21 (6yo) | Stallion | Bay | FR | Jewel |
| 148313C | Outlaw | Thoroughbred | SY13 (14yo) | Stallion | Black | CC | Lissa |