Food
Doves are typically seed eaters. There are a few species, called fruit doves, which live in tropical regions whose staple diet is fruit. There are very few of these in captivity. Since most of the doves in captivity have a staple of seeds we will talk about the seed eaters.

Unlike most pet birds (parrots, finches, parakeets, etc.), doves do not husk the seeds before eating them. They swallow the seeds whole. This is a plus for dove keepers since their is no question about the amount of food in a dish where with other birds the seed cups quickly fill up with husks making it harder to determine the amount of seed. The type of seeds eaten by doves largely depends on the species. While it is true that most doves will do quite well with an ordinary wild bird seed or canary mix from the garden or pet store, most breeders prefer to make their own combinations from various types of seeds. The most common seeds offered to medium sized doves (i.e. ringneck, senegal) are milo, wheat and millet. Small birds (i.e. diamond, cape, ruddy ground) prefer millet or canary grass seed but will often eat milo and wheat if offered. Large doves (i.e. bronzewing, red-eyed) will eat all of the above mentioned seeds as well as larger seeds like pop corn, peas and sunflower seeds. Many of the exotic doves also eat insects and berries in the wild. You may want to offer them maggots or meal worms to supplement their diet. The protein from insects is important so if your birds don't eat them when you offer them (or if they just gross you out) then you may want to offer them boiled eggs (mashed up) for the protein.

Grit
Grit should first and foremost include a calcium source (crushed egg shells, oyster shells). Other substances that may be included are; common sand (for food grinding purposes) and tiny bits of charcoal (digestion aid). You may be amazed to see your doves "eating" what seems like just little rocks. The do this for the reasons mentioned above. They need calcium for bone development and egg development. The charcoal helps in digestion and the sand helps grind up the seeds in their gullet. Grit should not be mixed with their food but offered in a separate dish. If you keep you aviary impeccably clean then you may just want to spread a handfull or two of grit on the ground occasionally. Recent studies by Dr. Wilmer J. Miller seem to conclude that sand for food grinding may not be necessary for domestic doves in captivity due to the freshness and softness of the seed that is offered. Doves in the wild require grit for food grinding because of the hard and older seeds they eat.