[4]: 25  The I was depicted in the traditional Đông Hồ paintings of Bắc Ninh province as a symbol of happiness, satiety and wealth.

The I entered the United States from Canada in the mid-1980s, and by the end of the decade the "pot-bellied pig" was being marketed as a pet.

It has a pronounced sway back and a large sagging belly, which in pregnant sows may drag on the ground.

It is particularly well adapted to the marshy and muddy terrain on which it usually lives: it has plantigrade feet, with weight borne on all four toes of each foot.

[2]: 616 Two principal types are recognised within the breed: the I-mo or Fatty I is the typical small short-legged pig, with small upward-pointing ears and a short snout; the I-pha or Large I is taller, has longer legs and a longer snout, with bigger ears held horizontally.