if the've completely 'ring barked' the trees they will struggle but if its just a bit it should callous over, as to the roses rabbits once' pruned' mine to ground level and they came back just as good but it does depend on the variety, can you put rabbit guards on the trees in future, as to the rest of the plants I rage a contsant war with rabbits--they especially like my bedding plants in the tubs!

its as pamq says. if they have completing removed the bark in a ring around the trunk then I am afraid they may well die. they may resprout [natural coppiced] from the trunk below the ring but it is a long shot. it is a matter of wait and see.