My interest in pig sex began over drinks at a bar in Burley, Idaho. My friend Becky was telling me that she couldn’t stand her job at a big hog farm outside of town. Each day she faced an unending line of sows filing into the room where she worked. Occasionally one of the 200-pound pigs broke ranks, knocking Becky down.

“Sometimes they get nervous when you stimulate them,” she said.

I set down my beer.

“Stimulate?”

“Yeah, for artificial insemination. Usually if you bring a boar around they’ll get in the mood. But if not you just have…