Do reindeer eat mistletoe

They will eat the berries of the mistletoe plant, but not the mistletoe leaves itself.

Mistle thrushes are known to be very territorial birds and will actually defend mistletoe bushes in their territory from other birds by chasing them away or pecking at them. It is especially common to see in winter, a mistle thrush pecking at the neck or wings of another bird two or three times bigger than itself until the bird flies away from the bushes.