An Iowa hog farmer was found guilty of first-degree murder this week in the rage-fueled corn-rake slaying of his wife, who was reportedly having an affair.

Todd M. Mullis, 43, was convicted Monday in the November slaying of Amy Mullis, 39, at their farm about 40 miles west of Dubuque.

Jurors came to their verdict after about 7½ hours of deliberations spanning two days.

Prosecutors charged that Todd Mullis had wanted to kill his wife for four years and was fuming that she was having an affair. He worried that he’d lose his farm if she divorced him.

That claim was backed up by Jerry Frasher, who testified during the trial that he was having an affair with Amy Mullis.

“I know she wasn’t happy,” said Frasher, a hog farm field manager. “She said she felt like a slave or a hostage around there. She said she was wanting [to leave Todd]. One time, she said if he ever found out [about the affair], she would disappear.”

Authorities initially reported that Amy fell and landed on the corn rake.

Todd told investigators that the couple’s son found Amy impaled on the four-pronged rake, which he removed before driving her to the hospital, where she was later declared dead.

But in December, an autopsy revealed that the woman had six puncture wounds — not four — and her death was ruled a homicide.

Police also revealed that Todd searched disturbing topics online, including “organs in the body,” “killing unfaithful women” and “what happened to cheating spouses in historic Aztec tribes.”

But during the trial, Todd’s attorney suggested Amy startled someone in the farm’s shed — prompting that person to impale her in the back while Todd worked in a nearby barn.

The jury clearly sided with the prosecution.

The first-degree murder conviction requires Todd to spend the rest of his life in prison, without parole.

With Post wires