rumen

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Related to rumens: ruminant digestion

rumen

(rū'men),
The anaerobic fermentative fore stomach of ruminants that consists of anatomically and functionally indistinct chambers; important role in the predigestion of the cellulose rich diet of herbivores. In addition to the specialized anatomic pouches, a rich biodiverse population of protists, viruses, fungi, bacteria, and enzymatic cofactors mix with water and alkaline saliva (during rumination) serves as a microenvironment within which volatile fatty acid (VFA) end-products (e.g., butyric acid, valeric acid) are generated (along with by-products such as belched or eructated methane and fine textured ingesta that passes to the rear gut to complete digestion and form feces). Average rumen holds 40 gal or 160 L of ingesta. Compartments include the reticulum and rumen (proper); rumen is compartmentalized by anterior and posterior pillars. Ventral and dorsal coronary pillars divide off the ventral and dorsal blind sacs, and by longitudinal pillars, which divide the main rumen compartment into the dorsal and ventral sacs, as well as the omasum and abomasum (the latter is the true monogastric type stomach).
See also: ruminant.
[L. throat, gullet]

rumen

(ro͞o′mən)
n. pl. ru·mina (-mə-nə) or ru·mens
The first division of the stomach of a ruminant animal, in which most food collects immediately after being swallowed and from which it is later returned to the mouth as cud for thorough chewing. Also called paunch.

ru′mi·nal adj.

rumen

a branch of the oesophagus of ruminants in which unchewed food is stored temporarily and from which it is regurgitated to the mouth for chewing (see RUMINANT STOMACH). Some cellulose is digested and absorbed in the rumen and bacterial action results in the synthesis of B vitamins there. Cellulase is produced by bacteria which may number 1 billion per cm3 in the rumen.
References in periodicals archive ?
Rumen fluid was sampled twice (after the 2-week period of high forage feeding on day 14 and after the 1-week period of high concentrate feeding on day 21).
Briefly, 1 mL of rumen fluid supernatant was mixed with 0.2 mL of metaphosphoric acid (250 g/L) and held at 4[degrees]C for 30 min.
In other words, the number of lignocellulases associated with Bacteroidetes is ~10 times when compared to Firmicutes or Bacteroidetes plays an important role in lignocellulose degradation, especially in the Vietnamese rumen. In contrast to this, biogas fermenters [17] show a ratio of 2.6:1, while hay-fed cow rumens [20] show a ratio of ~1.4:1.
Again, the ratios differ between earlier studies done on other biomass degrading environments (biogas fermenter [17] and hay-fed cow rumens [20]) (Table 2).
Rumen fluid was collected from a 1-yr-old Korean native goat and Saanen hybrid raised on Timothy (Phleumpratense) hay at a private goat farm in the Cheonan City area and slaughtered at a local slaughter house.
Other distinctive bacterial species such as Megasphaera elsdenii and Prevotella bryantii have also been used as DFM to stabilize or improve rumen function.
Although growth of the rumen generally is related to age or body weight, the best predicator of rumen weight may be intake of solid food.
Goats with rumen foreign body were emaciated and usually diarrheic.
But rumen bacteria can degrade this material, enabling cattle to derive nourishment from eating grass."
Incubation of all treatments in the rumen was with 7 g DM in each number-coded nylon bag (10x20 cm) with the pore size of ca.
Various carbohydrates contained in feedstuffs are degraded by rumen fermentation, which is carried out by consortium of microorganisms, i.e., the rumen microbial ecosystem.