ONWARD ROYAL c. 2001
ROYAL ACADEMY (USA) - CABARET QUEEN (USA), by GONE WEST (USA)

OP ART (BRZ) f. 1966
- , by

OPAL BAY (BRZ) f. 1993
ROI NORMAND (USA) - DEREIA (BRZ), by EGOISMO (BRZ)

OPERA (BRZ) f. 1954
WATER STREET (IRE) - DAMBORA (BRZ), by FORMASTERUS (FR)

OPERA-BALLET (BRZ) f. 2001
JULES (USA) - TRICKY BALLERINA (USA), by NUREYEV (USA)

OPERALOVER (BRZ) c. 2008
KNOW HEIGHTS (IRE) - HALEINE (BRZ) , by SKI CHAMP (USA)

OPERETA (BRZ) f. 1949
MARANTA (GB) - FINESSE (BRZ) , by FORMASTERUS (FR)

OPINIAO (BRZ) f. 1982
KURRUPAKO (BRZ) - OP ART (BRZ), by

OPLAND (BRZ) f. 1988
MILLENIUM (GB) - OLIVE (---), by

OPS f. 1949
HIGH SHERIFF (GB) - ELLIPSE (BRZ) , by FORMASTERUS (FR)