1. Grass is mixed with saliva, chewed forming cud and swallowed
2. Cud enters the rumen, the first chamber of the stomach. Cellulose digesting bacteria produce cellulase, breaking down cellulose in the grass into glucose. This ferments into organic acids and these are absorbed into the bloodstream. The process produces a lot of carbon dioxide and methane which is expelled
3. Fermented cud from the rumen enters the second stomach chamber, the reticulum. The cud is regurgitated from here back into the mouth to be rechewed
4. Rechewed cud is swallowed and enters the third chamber of the stomach, the Omasum. Water absorption occurs here
5. From the omasum food enters the fourth and final chamber of the stomach, the abomasum. Protein digestion occurs here
6. The products of digestion are absorbed into the blood in the small intestine