my neighbor has grapes muscidines growing all over her yard. i havent seen the dogs bother with them. if you keep them up where they cant get them and stuff they should be fine.

hers arent even fenced off. they run under the vines and everything.

if you need to you can get like mesh fencing to put around the bottom just in case some fall on the ground.

Yes, I'll be pruning so the grapes are out of reach. I'm thinking I'll only need to worry about it when the grapes are ripening. I don't know how easily they fall off of the vines.