Most rabbits should have free access to pellets at all times, unless you are directed otherwise by your veterinarian. A daily handful of hay aids in the mechanics of digestion and helps prevent many intestinal disorders. Legume hays, such as alfalfa and clover, are high in protein and most appropriate for young rabbits. Older and overweight rabbits can be offered grass or oat hays. Rabbits enjoy treats, but knowing what treats to give and how much to give are very important.
Rabbits have very delicate digestive systems, and too much of some foods can have dire consequences.
Fresh fruits and vegetables can be offered in small to moderate amounts. At the first sign of diarrhea, cut back. Do not give lettuce, cabbage or spinach. Also be careful of houseplants. Although you do not intend these as food, your rabbit may see it otherwise, and many are poisonous to rabbits.