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How to tell a horse's age by its teeth
Look a the color of the horse's teeth.
The color of a horse's teeth provide a general clue as to horse's age. The milk teeth are white, and the permanent teeth (which erupt at 2 to 5 years of age) that replace them are cream-yellow.

Choices: I. Check the teeth surface if you don't already have them (all horses have their teeth! ). A horse with a milk tooth disease should have the teeth checked by a vet. II. With increasing age they turn brown (20 years plus). Examine the shape of the chewing surface. III. The teeth that subside at 2 weeks are green and plump while the permanent teeth return at 4 to 7 days of age. Older horses' teeth will not have any white portion. IV. The teeth on a milk horse tend to look darker than those on a pony's teeth. Avoid this important factor when considering the age of your animal.
II.