Animals in this group of ruminants select plants and plant parts high in easily digestible, nutrient dense substances such as plant starch, protein, and fat. Concentrate selectors are very limited in their ability to digest the fibers and cellulose in plant cell walls. The rumen is sometimes called the “paunch.” It is lined with papillae for nutrient absorption and divided by muscular pillars into the dorsal, ventral, caudodorsal, and caudoventral sacs. The rumen acts as a fermentation vat by hosting …