They are, but their meat isn’t in as high demand and they’re more expensive and difficult to manage than cows, sheep and pigs.
Pigs are an easy one, they grow fast, do well in sheds, eat most of anything and don’t require a lot, cows and sheep are herd animals, easy to muster and relatively easy to fence while growing large and meaty fast.
Deer are more difficult to muster, running faster and more prone to splitting up, they can also jump high requiring taller and more expensive fencing.
People are missing the point of domestication. It’s not that deer run and jump better than pigs, cows or sheep. It’s the lack of herd structure that allows for a human to dominate and be recognized as the leader. Yes, their athleticism makes it difficult, but it’s the lack of tame-able (couldn’t decide how to spell it lol) traits that stick generation to generation that prevent it from being domesticated.
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.
They’d be a decent option if they couldn’t jump over fences. Most of the other domesticated herd animals prior to domestication would avoid trying to jump over a fence, so they could be corralled relatively easily. Even horses that have the capacity to jump would rather not. Deer jump as a primary way to escape predators…which doesn’t fare well for trying to corral them.
We tendes to domesticate creatures that are easy and offer a good yield.
Herd animals are easier to manage, we also needed to sustain them in captivity.
It’s why we domesticated dogs, rather than bears, or chickens instead of elephants. If we wanted deer meat we could hunt them, but you would not want to forage for wild chicken eggs, or milk goats in the wild, so it’s easier to bring them inside.
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