The rumen, also known as a paunch, is the largest stomach compartment in ruminants. The rumen and the reticulum make up the reticulorumen in ruminant animals. The diverse microbial communities in the
Rumen of a sheep from left. 1 Atrium ruminis, 2 Saccus dorsalis, 3 Saccus ventralis, 4 Recessus ruminis, 5 Saccus cecus caudodorsalis, 6 Saccus cecus caudoventralis, 7 Sulcus cranialis, 8 Sulcus longitudinalis sinister, 9 Sulcus coronarius dorsalis, 10 Sulcus coronarius ventralis, 11 Sulcus caudalis, 12 Sulcus accessorius sinister, 13 Insula ruminis, 14 Sulcus ruminoreticularis, 15 Reticulum, 16 Abomasum, 17 Oesophagus, 18 Spleen.