http://cotrancorp.com/cattleequipment.htm
A slaughter-house HR manager interviewed in Gig (wishlisted to me by the delicious Rebekah Jude!) said that at her work everything’s recycled, including the cow magnets. Cow magnets? Apparently, they’re fed to cows to collect the pieces of scrap wire they ingest (which would otherwise slice open their stomachs). (More on cow magnets.)