how much time would it take for a dog's vibrissae to be seen growing if they are plucked out?

Answer 1

I had a handler a couple years ago that SHAVED my dogs OFF. They started growing back within a week or so. Plucking, it may take longer.

Answer 2

Since dogs can retract them up to about a quarter of an inch when trying to pluck, it may seem as though they re-grow immediately. I agree with the answer above, and the show people I know shave about once a week, but don't recommend plucking because the dogs hate it (imagine that!).

Shaving weekly would be reasonable, as you'll probably see some growth within a week. Plucking will take longer, though probably not significantly longer, maybe 10 days to 2 weeks.