I had a horse named Henry .... sweetest guy. For stall bedding I would get loads of wood chips/shavings from a local logging mill. For whatever reason, I switched to straw for a while. Henry would be in a clean stall, fluffy straw up to his knees when I said ‘good night’. The next morning, the only straw in Henry’s stall was a spot of wet & poopy straw in the middle of his stall - the rest was gone ... he’d eaten it! Straw is not that appealing - most horses won’t eat it. He had hay & grain (which was gone) so maybe the straw was dessert! After a couple of mornings, finding him with no clean straw, he got changed back to shavings & only the brood mare got straw.
Yeah - THAT’S not right, LOL!
I wonder if it was oat straw.