- Parts of the horse.
Depending on breed, management and environment, the domestic horse today has a life expectancy of 25 to 30 years. It is uncommon, but a few animals live into their 40s and, occasionally, beyond. The oldest verifiable record was “Old Billy”, a 19th-century horse that lived to the age of 62. In modern times, Sugar Puff, who had been listed in the Guinness Book of World Records as the world’s oldest living pony, died in 2007, aged 56.
Regardless of a horse’s actual birth date, for most competition purposes an animal is considered a year older on January 1 of each year in the northern hemisphere and August 1 in the southern hemisphere. The exception is in endurance riding, where the minimum age to compete is based on the animal’s calendar age. A very rough estimate of a horse’s age can be made from looking at its teeth.
The following terminology is used to describe horses of various ages:
- Foal: a horse of either sex less than one year old. A nursing foal is sometimes called a suckling and a foal that has been weaned is called a weanling. Most domesticated foals are weaned at 5 to 7 months of age, although foals can be weaned at 4 months with no adverse effects.
- Yearling: a horse of either sex that is between one and two years old.
- Colt: a male horse under the age of four. A common terminology error is to call any young horse a “colt”, when the term actually only refers to young male horses.
- Filly: a female horse under the age of four.
- Mare: a female horse four years old and older.
- Stallion: a non-castrated male horse four years old and older. Some people, particularly in the UK, refer to a stallion as a “horse”.
- Gelding: a castrated male horse of any age.
In horse racing, these definitions may differ: For example, in the British Isles, Thoroughbred horse racing defines colts and fillies as less than five years old. However, for Australian Thoroughbred racing, colts and fillies are less than four years old.
(Adapted from Wikipedia)