mare

horse

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Last updated

June 30, 2026

Quick Summary

A mare is an adult female horse, specifically one that is fully mature or of breeding age. The term "mare" originates from Old English and has cognates in other Germanic languages, indicating its ancient roots in referring to horses.12

Female equines, including mares, typically reach puberty around one year of age but are not usually bred until they are two to four years old. Domesticated horses are seasonally polyestrous, meaning they have recurring fertile periods, primarily in the spring and summer. The gestation period for horses is about 11 to 12 months, and mares can often become pregnant again shortly after giving birth, though not all matings result in foals.3

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horse
Form and function
…employed as riding horses, while mares were kept for breeding purposes only. Geldings were used for work and as ladies’ riding horses. Recently, however, geldings generally have replaced stallions as riding horses. Young horses are known as foals; male foals are called colts and females fillies.
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…employed as riding horses, while mares were kept for breeding purposes only. Geldings were used for work and as ladies’ riding horses. Recently, however, geldings generally have replaced stallions as riding horses. Young horses are known as foals; male foals are called colts and females fillies.
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livestock farming
Management
…for a large band of mares to be average. Most large horse farms employ resident veterinarians to check for abnormalities or disease before breeding and to check mares for pregnancy 40 to 45 days after breeding. Because many mares conceive only every other year, expert assistance at foaling time is…
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…for a large band of mares to be average. Most large horse farms employ resident veterinarians to check for abnormalities or disease before breeding and to check mares for pregnancy 40 to 45 days after breeding. Because many mares conceive only every other year, expert assistance at foaling time is…
Read More