Pig
Pigs are an excellent source of meat and can be treated as a 'walking larder' in preparation for winter, as they represent meat that will never rot. A pig costs 38 meat cuts (2 cuts and 2 wooden bowls - this information maybe dated since wooden bowls get downgraded in value; in Version 3.14 a pig costs about 42 torches), the same as a sheep or a ram.
When culled, it produces about 109 cuts (pounds) of meat, 3 pounds of skin and about 0.2 pounds of fat. The skin takes 1 day to be tanned, becoming leather. Small pigs can carry 79 lbs.
Wild Pigs/Boars
Wild pigs (wild boars) can be found, and they are usually solitary, shy animals (sometimes found in groups of 3-5). They provide the same amount of meat, fat and skin as their domesticated counterparts, although they are very rare.
They usually will flee from the player, but sometimes, if you get too close (or just random) they will attack you.