This is a CONTACT-O-MAX™ boar cart, used to move a boar in front of a sow (in a crate), for heat checking. In a modern farm, the sows are in crates. To see if they need to get AI, you move a boar in front of them, like in this Spanish farm where they raise Iberico sows in crates:
They aren't using a boar cart, so things will take more or less time, depending on the cooperation of the boar. With a boar cart, they'd start the boar at the wall and move him across the row of sows. They'd heat-check the sows and mark down the ones needing AI. Then they'd come back and AI them.
The boar cart really shows how automated meat production has become. I suspect on day we'll do away with the animals altogether and just have machines produce meat for us.