5.2. Rumination Process
Dairy cattle typically graze for about 8 hours daily, swallowing grass with minimal chewing. When resting, they engage in rumination (chewing the cud), where semi-fluid material from the rumen or reticulum is regurgitated into the mouth for further chewing.
This process breaks down plant fibers, enhancing microbial action in the rumen and reticulum.
Initially, fungi attach to food particles, secrete enzymes, and weaken the fibrous structure, making it easier for bacteria and protozoa to invade.
This cooperative breakdown of forage ensures efficient digestion. Heavier, moister material gradually moves from the reticulum into the omasum.
Meanwhile, regurgitation, re-chewing (mastication), and re-swallowing (deglutition) occur every 1–2 minutes during rumination.
On average, each bit of dry matter consumed is regurgitated and chewed twice before continuing through the digestive tract.