Some people think the pig drank a Port a John, but considering the negative repercussions, I doubt it would have really done this.
Anticoagulants were described as being used to eradicate ground squirrels, which are a nuisance in California. This, in my opinion, is the most probable offender.
According to Glenn, they saw that no animals seemed to attempt to touch or consume the remains after they left it for around a day. The reason, however, is yet unknown.
He said that they had previously shot wild pigs on their land and that the corpses had never been blue. He also stated that they had contacted their neighbors and that none of them had reported any food dying.