| Ohio Babe | Rockhampton,
17-Nov-11 |
| Ohio Eagle | Thistledown,
20-Sep-24 |
| Ohio Girl | Spendthrift Australia Park,
21-Feb-21 |
| Ohio Joe | Penn National,
30-Aug-25 |
| Ohio Lady | Mahoning Valley,
16-Nov-23 |
| Ohio Munny | Mahoning Valley,
12-Mar-24 |
| Ohio Player | Thistledown,
26-Sep-24 |
| Ohio River | Mahoning Valley,
14-Feb-23 |
| Ohio Strong | Mahoning Valley,
29-Oct-25 |
| Ohiwa Sunset | Riccarton Park Synthetic,
29-Aug-24 |
| Ohiyesa | Cowra,
20-Jan-19 |
| Ohmali | Down Royal,
06-Sep-25 |
| Ohmikkiusofine | Mt Isa,
20-Apr-25 |
| Ohmygod | Hawkesbury,
13-Sep-12 |
| Ohmyviette | Naas,
29-Apr-25 |
| Ohnodonttakemehome | Plumpton,
10-Apr-23 |
| Ohnojoe | Wolverhampton,
06-Sep-24 |
| Ohope | Rosehill Gardens,
11-Oct-25 |
| Ohra Khan | Seoul,
17-May-25 |
| Ohshe'strouble | Launceston,
31-Oct-25 |
| Ohsotuf | Launceston,
08-Apr-18 |
| OHSOWISE | |
| Ohtani | Hawkesbury,
23-Oct-25 |
| Ohtwoohthreefive | Tampa Bay Downs,
21-Apr-24 |
| Ohzark | Down Royal,
06-May-24 |
| Oi Kumoyo | Ohi,
16-Jul-25 |
| Oi Oi Oi | Worcester,
24-Jul-25 |
| Oiche Chiuin | Leopardstown,
14-Jun-24 |
| Oiche Rua | Dundalk,
30-Oct-25 |
| OICHI | Quirindi,
23-Jun-11 |
| Oichinokata | Ohi,
22-Oct-25 |
| Oicho | Saga,
19-Oct-25 |
| Oide Leo | Kasamatsu,
10-Jun-25 |
| Oidemese | Nagoya,
25-Jun-25 |
| Oie De Toulouse | Mornington,
05-Sep-25 |
| Oihana | Pinjarra Park,
19-May-21 |
| Oil Can Knight | Santa Anita,
09-Jun-24 |
| OIL CAN RUBY | TRIAL Gawler,
30-Apr-12 |
| Oil Man | Horseshoe Indianapolis,
15-Aug-25 |
| OIL MONEY | Broome,
24-Jul-10 |
| Oil N Candy | Remington Park,
10-Nov-23 |
| Oil On Canvas | Tampa Bay Downs,
30-Dec-22 |
| Oiler | Thistledown,
14-Oct-25 |
| Oilisa | Ayr,
09-Oct-25 |
| Oilman | Nagoya,
30-Oct-25 |
| Oilysam | Gosford,
16-Aug-11 |
| Oimbari | Tatura,
08-Sep-25 |
| Oime Bien | San Isidro,
24-Apr-25 |
| Oinarisan | Kochi,
26-Oct-25 |
| Oink | Canterbury Park,
25-Aug-25 |
| Oirambuchi | Sapporo,
07-Sep-25 |
| Oiribukuro | Kasamatsu,
12-Jun-25 |
| Oiseau D'or | Kochi,
03-Aug-25 |
| Oiseau De Feu | Toulouse,
21-Mar-24 |
| Oishi | Colonial Downs,
02-Sep-25 |
| Oishi Ajisai | Mombetsu,
06-Nov-25 |
| Oishi Fujino Hana | Funabashi,
03-Oct-25 |
| Oishi Sakura | Mombetsu,
28-Oct-25 |
| Oishi Shakunage | Mombetsu,
16-Oct-25 |
| Oishi Teio | Mombetsu,
26-Aug-25 |