In barns cattle need some type of bedding in their freestalls to lie on - farms can use sawdust, straw, sand, etc. They chose a method where the bedding is produced every day by the barns' inhabitants!
In this system they scrape the barns with a vacuum sucker. It sucks the manure into a tank:
They empty the manure into a pit. They pump the manure into a machine. First the machine crushes the material and gets rid of anything hard that might have made its way onto the barn floor.
Then the manure goes through three rollers that compress all the liquid out of it. The liquid goes from a pipe into a liquid pit, and the hard material goes on a conveyor belt into a pile. Then they take that pile of dried manure and put it back in the freestalls.
Liquid squeezed out
Compression and dry matter
Mike Rassmussen and his cattle's new/used bedding
In the freestalls
It was a dry, soft-looking material. (I didn't feel it with my own hands, but I listened to Mike.) The whole process was interesting, since I'd never seen it before.
I told my brother about it, and he asked, "Do cows know they're lying in their own poop?"
According to Mike, though cows will try to eat almost any kind of bedding, including sand, he's never once seen them trying to eat this.