Found this interesting NPR article about researchers growing chimera embryos by inserting human stem cells into pig embryos.

http://www.npr.org/sections/health-...e-embryos-that-are-both-animal-and-human

Here's quite the quote:
"If a male chimeric pig mated with a female chimeric pig, the result could be a human fetus developing in the uterus of that female chimera," Newman says. Another possibility is the animals could give birth to some kind of part-human, part-pig creature.