Reindeer are the only deer to be widely domesticated. They’re used for labor, meat, milk, and hides & tools. Some people even ride on them like horses. [https://youtu.be/XO1O9WFlQmA](https://youtu.be/XO1O9WFlQmA)
[nat geo doc on domesticated deer](https://youtu.be/XX6VB-y9_Pk)
So it’s possible it’s just not widely seen in the rest of the world because cows, pigs, sheep and goat are more readily available and more thoroughly developed with specific breeds for specific needs.
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