One of the fawns two tails had to be amputated after the fight, during which it became separated from its mother.
Vets treating the animal say that its extra limbs are the result of an identical twin that did not fully develop in the womb.
The fawn has two distinct pelvises, and uses one leg from each pelvis when it walks.
It is really an anomaly, said Dan Pate of the West Rome Animal Clinic in Rome, in the US state of Georgia.
Somehow it has a fairly normal gait, although the centre legs seem to get in the way."
The deer was brought in for treatment after being attacked by dogs belonging to walkers Melissa and Alan Dunagan.
"It wasnt until after we put the dogs back in the house and were about to release the fawn that we realised it had six legs, Mrs Dunagan said.
Vets expect the deer to recover completely, after which it will likely be taken to deer facility at the University of Georgia.
