Scientists at the University of Arkansas (USA) said that although it is not 100% accurate, by examining the teeth, one can roughly predict the age of a horse without knowing the date of birth.
A foal is usually born with 4 incisors (2 upper jaws, 2 lower jaws). If not, after 8 days they will grow. Eight weeks later, the horses begin to teething and about 8 months old, they have enough baby teeth. After that, baby teeth gradually fall out and by about 2.5 years old, they will have permanent incisors. 5 years old, the horse will have enough permanent teeth.
Baby teeth are usually pale in color, shorter than permanent teeth. In 6-year-old horses, their incisors also often recede to look like a small cup and they fill up over time.
By about 10 years old, the gums next to the molars will grow a part called the Galvayne groove. This groove reaches half the length of the teeth by the time the horse reaches 15 years of age. Males usually have 40 teeth, while mates have only 36 teeth.
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