While not centered solely on pigs, Joel Salatins books go into all livestock care, including pigs. He describes how he uses them in his composting system in "You Can Farm"and "Folks, This Ain't Normal", and also has a book titled "The Marvelous Pigness of Pigs" although I haven't read that one yet. A lot of the writing is more about the abomination of the factory farming model and what we can do to move past that.
