This BBC news article reports that a farmer was eaten by his pig:
Authorities are investigating how a farmer in the US state of Oregon was devoured by his pigs.
Terry Vance Garner, 69, went to feed his animals last Wednesday on his farm by the coast, but never returned.
His dentures and pieces of his body were found by a family member in the pig enclosure, but the rest of his remains had been consumed.
I do know that hogs are omnivorous animals, but I doubt if there are any such behavioural traits/instincts that would make a pig eat a person. It is unnatural for an animal, which has been domesticated for centuries, to exhibit such behaviour.
Is there any evidence to support or disprove this? For example, any other documented reference of a pig actually eating a person? Also are there any other cases apart from pigs, where unexpected domestic animals have preyed or scavenged on human beings?