The wet sheen of cud is a quiet rebuke to the cartoon of a cow as a single oversized stomach. Grass enters not one vat but a four-room biological factory: rumen, reticulum, omasum, and abomasum. Each chamber changes the bargain between animal and pasture. Nothing about it is simple.That division is less a curiosity than agriculture's hidden transaction. In the rumen, microbes ferment cellulose, a ...More