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A ruminant is any hooved animal that digests its food in two steps, first by eating the raw material and regurgitating a semi-digested form known as cud, then eating (chewing) the cud, a process called ruminating. Ruminants include cattle, goats, sheep, alpacas, llamas, giraffes, bison, buffalo, deer, wildebeest and antelope. The suborder Ruminantia includes all those except the camels and llamas, which are Tylopoda. Ruminants also share another anatomical feature in that they all have an even number of toes. According to the Bible, “the hare . . . is a chewer of the cud.” (Leviticus 11:6) François Bourlière (The Natural History of Mammals, 1964, page 41) says: “The habit of ‘refection,’ or passing the food twice through the intestine instead of only once, seems to be a common phenomenon in the rabbits and hares. Domestic rabbits usually eat and swallow without chewing their night droppings, which form in the morning as much as half the total contents of the stomach. In the wild rabbit refection takes place twice daily, and the same habit is reported for the European hare.” In this regard, the work Mammals of the World (by E. P. Walker, 1964, Volume II, page 647) states: “This may be similar to ‘chewing the cud’ in ruminant mammals.” This article does not adequately cite its references or sources. ... Cud is a bolus of semi-degraded food regurgitated from the reticulorumen of a ruminant. ... COW is an acronym for a number of things: Can of worms The COW programming language, an esoteric programming language. ... Species See Species and subspecies The goat is a mammal in the genus Capra, which consists of nine species: the Ibex, the West Caucasian Tur, the East Caucasian Tur, the Markhor, and the Wild Goat. ... Species See text. ... This article is about a breed of domesticated ungulates. ... Binomial name (Linnaeus, 1758) The llama (Lama glama) is a South American camelid, widely used as a pack animal by the Incas[1] and other natives of the Andes mountains. ... Binomial name Linnaeus, 1758 Range map The giraffe (Giraffa camelopardalis) is an African even-toed ungulate mammal, the tallest of all land-living animal species. ... Species †B. antiquus B. bison B. bonasus †B. latifrons † †B. priscus Herd of bison grazing in Elk Island National Park, Alberta, Canada. ... Binomial name (Linnaeus, 1758) Subspecies B. b. ... “Fawn” redirects here. ... “Gnu” redirects here. ... Genera Aepyceros Alcelaphus Antidorcas Antilope Cephalophus Connochaetes Damaliscus Gazella Hippotragus Kobus Madoqua Neotragus Oreotragus Oryx Ourebia Pantholops Procapra Sylvicapra Taurotragus Tragelaphus and others Antelope are herbivorous mammals of the family Bovidae, often noted for their horns. ... Families  Tragulidae  Moschidae  Cervidae  Giraffidae  Antilocapridae  Bovidae The biological suborder Ruminantia includes many of the well-known large grazing or browsing mammals: among them cattle, goats, sheep, deer, and antelope. ... Species  Lama glama  Lama pacos  Lama guanicoe  Vicugna vicugna  Camelus dromedarius  Camelus bactrianus The four llamas and two camels are camelids: members of the biological family Camelidae, the only family in the suborder Tylopoda. ... Families Suidae Hippopotamidae Tayassuidae Camelidae Tragulidae Moschidae Cervidae Giraffidae Antilocapridae Bovidae The even-toed ungulates form the mammal order Artiodactyla. ...

Explanation

Ruminants have a fore-stomach with four chambers. These are the rumen, reticulum, omasum, and abomasum. In the first two chambers, the rumen and the reticulum, the food is mixed with saliva and separates into layers of solid and liquid material. Solids clump together to form the cud (or bolus). The cud is then regurgitated, chewed slowly to completely mix it with saliva and to break down the particle size. Fibre, especially cellulose and hemi-cellulose, is primarily broken down into the three volatile fatty acids, acetic acid, propionic acid and butyric acid in these chambers by microbes (bacteria, protozoa, and fungi). Protein and non-structural carbohydrate (pectin, sugars, starches) are also fermented. The rumen, also known as the fardingbag or paunch forms the larger part of the reticulorumen, which is the first chamber in the alimentary canal of ruminant animals. ... This article is about an anatomical part. ... The omasum, also known as the manyplies, is the third compartment of the stomach in ruminants. ... The abomasum is the fourth and final stomach compartment of the stomach in ruminants. ... Cellulose as polymer of β-D-glucose Cellulose in 3D Cellulose (C6H10O5)n is a polysaccharide of beta-glucose. ... Volatile fatty acids are fatty acids with a carbon chain of six carbons or fewer. ... Acetic acid, also known as ethanoic acid, is an organic chemical compound with the formula CH3COOH best recognized for giving vinegar its sour taste and pungent smell. ... Propionic acid (systematically named propanoic acid) is a naturally occurring carboxylic acid with chemical formula CH3CH2COOH. In the pure state, it is a colorless, corrosive liquid with a pungent odor. ... Butyric acid, (from Greek βουτυρος = butter) IUPAC name n-Butanoic acid, or normal butyric acid, is a carboxylic acid with structural formula CH3CH2CH2-COOH. It is notably found in rancid butter, parmesan cheese, and vomit, and has an unpleasant odor and acrid taste, with a sweetish aftertaste (similar to ether). ... Wikisource has an original article from the 1911 Encyclopædia Britannica about: Protozoa Protozoa (in Greek proto = first and zoa = animals) are single-celled eukaryotes (organisms whose cells have nuclei) that commonly show characteristics usually associated with animals, most notably mobility and heterotrophy. ... Divisions Chytridiomycota Zygomycota Ascomycota Basidiomycota The Fungi (singular: fungus) are a large group of organisms ranked as a kingdom within the Domain Eukaryota. ... Pectin, a white to light brown powder, is a heterosaccharide derived from the cell wall of higher terrestrial plants. ... This article deals with sugar as food and as an important, widely traded commodity; the word also has other uses; see Sugar (disambiguation) A sugar is a form of carbohydrate; the most commonly used sugar is a white crystalline solid, sucrose; used to alter the flavor and properties (mouthfeel, perservation... Starch is a complex carbohydrate which is insoluble in water. ...

Even though the rumen and reticulum have different names they represent the same functional space as digesta can move back and forth between them. Together these chambers are called the reticulorumen. The degraded digesta, which is now in the lower liquid part of the reticulorumen, then passes into the next chamber, the omasum, where water and many of the inorganic mineral elements are absorbed into the blood stream. After this the digesta is moved to the last chamber, the abomasum. The abomasum is the direct equivalent of the monogastric stomach (for example that of the human or pig), and digesta is digested here in much the same way. Digesta is finally moved into the small intestine, where the digestion and absorption of nutrients occurs. Microbes produced in the reticulo-rumen are also digested in the small intestine. Fermentation continues in the large intestine in the same way as in the reticulorumen.

Almost all the glucose produced by the breaking down of cellulose and hemicellulose is used by microbes in the rumen, and as such ruminants usually absorb little glucose from the small intestine. Rather, ruminants' requirement for glucose (for brain function and lactation if appropriate) is made by the liver from propionate, one of the volatile fatty acids made in the rumen ^{[citation needed]}. Glucose (Glc), a monosaccharide (or simple sugar), is the most important carbohydrate in biology. ... In biology the small intestine is the part of the gastrointestinal tract (gut) between the stomach and the large intestine and includes the duodenum, jejunum, and ileum. ...

Culture

One of the requirements of kashrut for a land animal is that the animal ruminates. Look up kosher in Wiktionary, the free dictionary. ...

Other uses

The verb to ruminate has been extended metaphorically to mean to thoughtfully ponder or to meditate on some topic. Similarly, ideas may be chewed on or digested. Chew the (one's) cud is to reflect or meditate. Look up metaphor in Wiktionary, the free dictionary. ... A large statue in Bangalore depicting Shiva meditating Meditation describes a state of concentrated attention on some object of thought or awareness. ...

• Monogastric

• Digestive Physiology of Herbivores - Colorado State University