In cows, goats, sheep, and other ruminants the stomach is composed of multiple chambers: the rumen, reticulum, omasum, and abomasum. This design facilitates the break down of the thick cell walls of plants and the digestion of cellulose in a multi-step process involving the formation of regurgitation of cud. Ruminant digestion is also heavily dependent on symbiotic bacteria and protozoa that inhabit the stomach. Rodents are not ruminants, but similar to those species usually reingest material that was already partially digested. Instead of cud, however, rodents ingest their own fecal pellets in order to obtain a larger proportion of the nutrients available in the plant food they typically consume.

This widefield image of a rat stomach tissue section was produced by probing the specimen with Alexa Fluor 488, Texas Red, and Hoechst 33342. The Alexa Fluor dye was conjugated to phalloidin, targeting the cytoskeletal F-actin network, and Texas Red was conjugated to WGA in order to localize a red fluorescent tag to the Golgi complex. The nuclear counterstain Hoechst 33342 was employed to visualize cell nuclei. Images were recorded in grayscale with a 12-bit digital camera coupled to a Nikon Eclipse 80i microscope equipped with bandpass emission fluorescence filter optical blocks. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.