Fresh hay is beneficial to rabbits in that it helps them produce heat and it helps keep hairballs from forming. Timothy, oat, or grass hay should be used. Avoid alfalfa hay as the rabbit already gets plenty of alfalfa in its regular pellets. Also, be sure not to feed straw. Straw has little nutritional value.
Rabbits enjoy treats, and they will eat most any vegetation. However, certain treats are better than others, and some treats can even be harmful. The best treats are fresh fruits and vegetables such as apple slices, baby carrots (or carrot slices), raisins, and other such treats that are not overly high in water content. Treats that are too watery (melon, lettuce, etc.) can cause the rabbit to get the runs. Other good treats are pieces of shredded wheat, pieces of wheat bread, and dried bananas.
Fresh water should be available to rabbits at all times. Do not rely on moist treats to provide enough water for a rabbit. On hot days, check the water level at least twice a day, and it is a good idea to replace it with cool water when you check the level. If the water is frozen, even if the rabbit can lick or chew on the ice, replace the ice with fresh water. Ice does not provide enough liquid for a rabbit.
The amount of feed provided depends on the age and the size of the rabbit:
Birth to three weeks
Three weeks to weaning (6 to 8 weeks)
Mother’s milk and unlimited pellets and hay
Eight weeks to twelve weeks
Unlimited pellets and hay. Very limited amounts of treats, being especially careful to restrict moist treats.
Twelve weeks to adulthood (6 to 8 months, depending on the breed)
One ounce of feed per pound of body weight is the norm. However, some rabbits have higher or lower metabolisms. If the rabbit feels a little thin, increase the feed. If the rabbit feels a little fat, decrease the feed. Provide a handful to unlimited amounts of hay each day. A treat may be given daily if the rabbit is used to it. If not, build up to the point where it can have one treat a day.