In the United Kingdom, this term also applies to a field for a general automobile racing competition, particularly Formula 1.
Larger paddocks may have grass maintained in them, but many are dirt or a similar natural surface.
In the American West, such an enclosure is often called a corral, and may be used to contain cattle or horses, occasionally other livestock.
However, high-value stallions are rarely used for breeding in this manner, as uninterested mares may severely injure them.
[1] In Australia and New Zealand the word paddock is used instead of field to describe a section of farmland, regardless of size.