What Kind Of Dwarf Pigs Do I have?

Question
I have several miniature pigs in my care that are not
Pot Bellies. Do you have any suggestions about how I
could find out what breed they are or at least narrow
the possibilities? Some are all black, some are all white,
some are spotted, and some have saddles. All look just
exactly like full size farm pigs except they are all
under 50 lbs. full grown. Many are under 30 lbs. as
adults. I'm really interested in finding out more about
these pigs. People ask me all the time and I get tired
of telling them, "Oh, they're just miniature pigs." They
don't have pushed in faces or wrinkles all over like Pot
Bellies do. Also, their backs are very parallel to the
ground and their bellies don't almost drag the ground
like Pot Bellies. I would appreciate any help you could
give or at least point me in the right direction to find
out.

Thank you much,

Angie. ( : !


Answer
Your pigs, like most small pet pigs in the US, are probably a mix of several strains of Asian miniature pigs, along with a little feral.
Most US feral pigs are descended more or less from European boars, and have the straight snout and back. The babies are spotted. Most wild feral babies loose the spots in the first year, but when domesticated ferals are bred with other miniature pigs, the babies may retain their spots.
Swedish White pigs (this strain was imported to the US from Sweden) have long, almost wrinkle free snouts and straight backs. The original pigs were white or white with black spots or markings. But by the early 90s they were crossed with other strains to produce all black or black and white pigs. So there's a possibility your pigs may be predominantly Swedish White. But without breeding records or registration papers, the best that anyone can do is guess.
NAPPA www.petpigs.com and NCOPP www.ncopp.com are the only two organizations that I know of that are still maintaining breeder registries. They may or may not be able to help you identify your particular pigs.
The University of Oklahoma has a web page with photos and descriptions of many breeds of pigs, at http://www.ansi.okstate.edu/breeds/swine/