They will if they have stomach upset. I've seen pigs on antibiotics actively seek out the poop of healthy pigs (much to the dismay of the healthy pig sometimes!) It helps to replenish needed gut flora that are killed by the antibiotics.I think caecotrophs are squishier and have a different smell to them than normal poos. They must feel it or smell it or something. If we want to make it even grosser, I wonder if a piggy would ever take someone else's poop LOL