| Name | Color | Sex | Year of birth | Microchip | Sire | Dam | Breed | Breeder |
|---|---|---|---|---|---|---|---|---|
| Unperturbable | bay | f | 1964 | Victoria Park | Sphinxlike | Thoroughbred | Canada | |
| Unpredictable | d.-bay | c | 1979 | Tri Jet | Capricious Girl | Thoroughbred | USA | |
| Unpriced Gift | d.-bay | f | 2017 | не введен | 1144-5 Plum Drop | 2805-5 Aneka | Thoroughbred | Mr Kolpokchi A.A. |
| Unreal Baby | chestnut | f | 2014 | Flatter | Flowerette | Thoroughbred | USA | |
| Unreal Zeal | d.-bay | c | 1980 | Mr. Prospector | Quick Nurse | Thoroughbred | USA | |
| Unreality | f | 1974 | In Reality | Starstrand | Thoroughbred | USA | ||
| Unromantic | d.-bay | f | 1962 | Hasty Road | Elsewhere | Thoroughbred | USA | |
| Unsociable | d.-bay | f | 1969 | Never Bend | Vassar Grad | Thoroughbred | USA | |
| Unsuspected | bay | f | 1972 | Above Suspicion | Chevanstell | Thoroughbred | Great Britain | |
| Unter Officer | chestnut | c | 2021 | 643099200013036 | 1736-7 A Bit Fire | 4849-6 Urbana | Thoroughbred | Mr. Kolosov S.P. |