| | OTELIA | 1969 | 1969 |
| | OTERLO | 1978 | 2002 |
| | OTHELLO | 1874 | 1875 |
| | OTHON | 1937 | 1969 |
| | OTIS TARDA | 1884 | 1916 |
| | OTIS TETRAX | 1916 | 1916 |
| | OTTAWA MAYBANK | 1946 | 1946 |
| | OTTAWA MAYCLIFF | 1946 | 1946 |
| | OTTAWA MAYSTAR | 1946 | 1946 |
| | OTTER | 1963 | 1984 |
| | OTTERLO | 1978 | 2001 |
| | OTTIS TARDA | 1884 | 1916 |
| | OTTO | 1926 | 1930 |
| | OTTO DANIELSEN | 1978 | 1995 |
| | OTTO FISCHER | 1921 | 1923 |
| | OTTO PORR | 1930 | 1950 |
| | OTTO SCHMIDT | 1915 | 1935 |
| | OTTOLAND | 1901 | 1909 |
| | OTTOLAND | 1916 | 1939 |
| | OTZTAL | 1996 | 1996 |
| | OUADY | 1884 | 1884 |
| | OUD BEIJERLAND | 1930 | 1930 |
| | OUDE MAAS | 1918 | 1918 |
| | OUDERKERK | 1915 | 1922 |
| | OUDERKERK | 1954 | 1954 |
| | OUDEWATER | 1919 | 1930 |
| | OUDEWATER | 1937 | 1937 |
| | OUDKARSPEL | 1919 | 1919 |