I agree with the previous posters, wild rabbits do not need any help. Your backyard is a giant buffet table to them, and the grass etc. that they normally eat is much healthier and better for them than any man-made food is. Plus the fact that if they overeat on what you are giving them, they may even get overweight and have a harder time getting away from predators. If you have been feeding them for a while, the best thing to do is to slowly reduce the amount you are putting out to get them to adjust again to their natural diet.