In addition to the formulated diet, you can feed a good variety of fresh vegetables to make up about 25% of the pig's diet. Foods such as celery, cucumbers, peppers, carrots, potatoes and some greens are good choices (but try to limit the starchy vegetables like potatoes). Some fruits can be fed as well, but only in moderation due to the high sugar content. Most pigs love treats like apples, grapes and raisins, but these are good to reserve as treats to be used in training. Extra fiber can be provided by feeding hay (e.g. alfalfa) and some experts recommend adding bran to the diet.
Pigs should also be allowed opportunity to root in soil and graze on grass (not treated with chemicals or fertilizer). Pigs are susceptible to selenium deficiency but in most areas if they are allowed to graze and root in the soil they will get enough. If you live in an area with soil deficient in selenium you may need a mineral supplement. Check with your local pot bellied pig veterinarian for advice on this.
Reprinted from About.com
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