Not hit a deer, but you get plenty at Thetford legging it in front of you, as well as Hares and badgers.
A mate had to emergency avoid a badger that bumbled out in front of him…..
I ran a squirrel over once by accident, but it scampered off before I could really see what happened. Hopefully I didn’t crush all it’s bodily insides….!
When I lived in Bavaria I was a bit lost & popped out of a bit of forest into a grassy field. While skirting around the edge of it, a herd of around 20 large deer flew out of the forest (not literally flew) across my path and I almost ran into them. They were large roe deer; probably taller than I was sat on the bike. Shat me up a bit. Once I gained my composure I carried on, only for another group about half the size to do the same bloody thing around 50m or so up the field!