The Ruminant Stomach - Online Biology Dictionary The Ruminant Stomach EUGENE M. MCCARTHY, PHD Google+ Profile Ruminant stomach The ruminant stomach is a multi-chambered organ found in ruminants (see picture at right). It is usually composed of four separate chambers and allows digestion of large quantities of plant matter that would be relatively indigestible for most other types of mammals, in particular grass and the leaves. The upper part of this stomach is where fermentation of green foliage takes place with help from anaerobic bacteria . These bacteria allow ruminants to break down cellulose , a major component of all leaves. The slow fermentation and digestive processes that occur within this complex stomach also allow better absorption nutrients as they go on from the stomach to pass through the intestines . Having a ruminant stomach is a big advantage because it makes it so easy to find something to eat (cellulose is the most abundant organic compound on earth). What are ruminants? Goat chewing cud ( Enlarge ) Ruminants are mammals that chew cud, that is, they regurgitate partially digested solids (the cud), and chew them again. They then re-swallow the cud.

This re-chewing of the cud to further break down the semi-digested food is called “ruminating.” Such animals include many members of the order Artiodactyla, such as cattle, goats, sheep, bison, yaks, water buffalo, antelope, deer, and giraffes, but not pigs, which are also artiodactyls. The stomach of a pig is simple like that of a human being, except for the presence of a small pouch or diverticulum at its cardiac end. Camelids (camels, alpacas, and llamas) are artiodactyls and ruminate, but they have three-chambered stomachs. How a ruminant stomach works A ruminant begins by chewing and swallowing its food. The ingested matter is then softened within the first two chambers of the stomach, the rumen and reticulum , which communicate freely with each other (considered as a single unit, these two chambers are called the “reticulorumen”). Microbes convert the food, particularly cellulose , into less indigestible substances. The animal regurgitates the cud, and chews it again, and re-swallows it.

The liquid portion of the material within the reticulorumen, passes on to the next chamber, the omasum . Here, water and minerals are absorbed into the blood. The remaining matter moves into the fourth chamber, the abomasum , which is equivalent to the ordinary stomach found in non-ruminants. Leaf Monkeys Hanuman Langur at Mudumalai National Park, India ( Enlarge ) Leaf monkeys, primates of the genera Semnopithecus amd Trachypithecus, also ruminate. Like other ruminants, the slow fermentation that occurs within their chambered stomachs allows them to digest high-cellulose leaves that most other types of mammals cannot, even leaves containing toxins . It also allows them to eat a wider variety of other types of foods than do other monkeys. For example, the Hanuman Langur (Semnopithecus entellus) regularly eats fruits with high strychnine content that would kill most monkeys. So leaf monkeys can not only feed off a wider variety of food items than other monkeys, but also digest those foods more efficiently than do other primates.

Some marsupials ruminate ( Enlarge Image ) Kangaroos and certain other Australian marsupials also ruminate. Marsupials are mammals in which the young emerge from the womb at a very early stage of development and attach themselves to the mother's nipples. Many, but not all, marsupials have a pouch in which development of the offspring occurs. The Virginia Opossum (Didelphis virginiana) is a well known example (though it is an American marsupial and does not ruminate). Synapsida: Why Cows Have Four Stomachs A random wander through the world of mammals Sunday, 7 August 2011 Why Cows Have Four Stomachs (If all you want to know is what animals do, and what animals don't, have a four-chambered stomach, the shorter answer is here ). The stomach is an organ found in almost all vertebrates. Although there is considerable variation among the different groups, and there are some fish that don't have one at all, in general it has two functions.

Firstly, it helps to store food for later digestion so that you don't constantly have to be eating, and secondly, it begins the digestion of food both by physically grinding it up and by mixing it with acid and digestive enzymes. Sometimes these functions are separated to some extent - for example, birds have a large crop for food storage, and a smaller true stomach below it that digests the food, and includes a muscular, grinding gizzard (a useful thing when you have no teeth). But the most complex stomachs of all are found in mammals. A cow does, indeed, have four stomachs. Or, at least, it has a stomach divided into four separate chambers, which amounts to the same thing. Nor, of course, are cows alone in this. It's a feature found throughout the cattle family, which is a fairly large group consisting of over a hundred species - most of them antelopes, although it also includes the sheep and goats. The cattle were not the first family to evolve the feature, and we know that because its also found in all their close relatives, including such animals as deer and giraffes.

In fact, the only truly cloven-hoofed animals that don't have four stomachs are the pigs and peccaries - which is why they aren't kosher . In fact, we can group all the mammals that have this four-chambered stomach together. This group are called the "pecorans". Why not just "ruminants"? We'll get onto that later. Animals with four-chambered stomach in blue. For the sake of simplicity, the above chart excludes the chevrotains, which do have the four-chambered stomach, but probably branch off even before the giraffes. For the same reason, I have also grouped multiple related families together. For example, peccaries are grouped in with pigs (since they probably have a common ancestor) and pronghorns in with giraffes. And the "etc." for hippos is a surprisingly large one that I'll leave for another day! So, why bother with four stomachs, when most other animals do perfectly well with just the one? In a word: grass.

Well, not just grass, although that is the major culprit; many other leaves also play a part, as is obvious from the wide range of different animals included in the Pecora. One thing they do all have in common, though, is that they are all herbivores. The problem with being a herbivore is that many leaves, and grass in particular, are not especially digestible or nutritious. You have to eat a lot of them to get enough nutrients, which is why big, herbivorous animals spend a lot more time grazing than animals like lions do hunting. If you really must eat plants, the easiest option is to eat fruit, or at least soft, young leaves, and there are a number of mammals that do that, especially among primates. But there is only so much fruit to go round, especially if you aren't a forest-dwelling animal, so the big grazing animals had to come up with some way of extracting the maximum amount of nutrition from the relatively poor quality food they are left with. Which is where the four stomachs come in. The first stomach - or first chamber - is the rumen.

This is a large chamber, often with a rather complex shape, that helps to store the food after it is eaten. It has no digestive lining, and strictly speaking, like the crop of birds, is just an extension of the oesophagus, or gullet. However, while it can't digest food itself, it does contain numerous bacteria, protozoans, and even some fungi, all of which help to ferment the food, so that that the animal can digest it later on. This fermentation produces a lot of gas, and ruminants do, indeed, belch a lot of methane as a result. The liquid resulting from this process trickles down into the second chamber, the reticulum, where further fermentation occurs, but the solid food is partially regurgitated up into the mouth for a second round of chewing. This, of course, is "chewing the cud", and it helps to further break down the food. The reticulum is a spongy organ, but otherwise very similar to the rumen, and is the source of the food known as honeycomb tripe . The chewed cud, along with the fermented liquid, however, then passes straight on to the third chamber, the omasum.

Like the first two chambers, the omasum has no digestive glands, and it mainly serves to continue to mash up the food between its many folds. It probably also absorbs at least some of the nutrients that have already been released by fermentation, but it is the smallest of the three chambers, and soon passes the food on to the fourth and final chamber, the abomasum. It's here that the digestive glands are located, secreting acid and enzymes to break the food down, just as the stomach of any other mammal does. Indeed, the abomasum is the only "real" stomach; everything else is just part of the oesophagus. From here on, digestion is fairly normal. It may not have escaped your attention, however, that, wide though the group of "pecorans" is, they aren't the only large grazing animals. Pigs aren't really grazers, they get by by eating a wider range of more digestible food, but what about camels or horses, for example? If they don't have four-chambered stomachs (and they don't), how do they extract nutrients from grass? Well, firstly, the pecorans are not the only ruminants.

Camels, llamas, and their kin also chew the cud, and they have a three-chambered stomach that does look rather like that of cattle, only without the omasum. Again, only the last chamber is the real stomach, and this similarity meant that, for a long time, it was thought that the pecorans had evolved from camel-like animals by the addition of an extra chamber between the reticulum and abomasum. But we now know that can't be right, because pigs and hippos - which have a relatively normal stomach - are closer to cattle than they are to camels. Which means that camels evolved their three "stomachs" entirely separately from the pecorans evolving their four. It is viable, however, to ferment the food without chewing the cud. Kangaroos do this; they have a really large stomach, suitable for fermentation, but it only has one chamber, so they can't separate the cud out to chew it - which is less efficient, but somewhat quicker than, the ruminant process. Horses, however, take a completely different approach.

Here, the large intestine is greatly expanded, and contains fermenting bacteria, so that it can act just like the first two chambers of the ruminant stomach. Indeed, this structure is usually much bigger than the stomach itself, just as the fourth chamber of the pecoran stomach is smaller than the first one. We see this hindgut fermentation system, not just in horses, but also in rhinos, tapirs, koalas, rabbits, and a whole host of other herbivores. Having the fermentation chamber positioned behind the stomach makes chewing the cud impossible, but it does mean that the animal can process food more quickly, and that it's already partly digested by the time fermentation begins, which does have some advantages. On the downside, the very fact that it's quicker means that it isn't quite as efficient as rumination, and that you do have to keep eating to keep food moving through your digestive tract. A way to get the best of both worlds is, rather than passing fermented food back up to the mouth from the stomach, to ferment it in the hindgut, pass it out through your back end, and then eat it again.

It's much the same idea as chewing the cud, if rather less pleasant from a human perspective, and it is, of course, what rabbits do. Humans only have one stomach, and no large fermenting chamber in our hindguts. We are not herbivores; if anything, apart from our teeth, our digestive system looks more like that of a pure carnivore than that of an omnivore. Yet, obviously, we can survive perfectly well on a vegetarian diet. This is because we, unlike any other animal, have invented cooking. If you tried to survive on a diet of nothing but uncooked leaves, nuts, and so on, you would quite possibly die, and you certainly would if you tried to live off grass. Having said that, the fact that humans did not evolve to be herbivores is a pretty poor argument against vegetarianism. We did not evolve to live in houses, either, and yet we do that. We are sentient beings, capable of choosing how we live, and we don't have to be slaves to our evolutionary history if we don't want to be. But that's a whole different debate.

Giraffes: WhoZoo Habitat:ï¿½ Dry, tree-scattered terrain south of the Saraha Status:ï¿½ Not threatened Diet:ï¿½ Acacia tree leaves, grass, and low laying bushes Diet in the Zoo:ï¿½ Herbivore diet Location in the Zoo:ï¿½African Savannah Physical description: Average male height 17 feet (5.3 meters), Weight averages 1800 pounds (800 kg).ï¿½ The hoofed animals have chestnut brown blotches on buff colored fur.ï¿½ The spots on the fur darken as the animal ages.ï¿½ Giraffes have very long, flexible tongues and lips to go along with their long slender necks. The male giraffe's neck continues to grow after sexual maturity has been reached, whereas the females' neck stops growing when maturity is reached at about 10 years of age. Giraffes have seven vertebrae in their necks, just as humans do. They have very large eyes on the sides of their head, atop a periscope like neck, that give them wonderful eyesight.

Also on the top of their head, they carry 2-4 stubby horns that lie under the skin. Their 8 inch ears give them a good sense of hearing. ï¿½ ï¿½ The size of these giraffes can really be appreciated when they are seen standing next to these zebras.ï¿½ Photo courtesy of Africam General information: Giraffes tend to travel in herds that vary from as few as 3 to as many as 15 in number.ï¿½ The females tend to stick together in family groups while they lose some of their young males to all-bachelor groups.ï¿½ These herds may separate to graze for the day, but they always stay within hearing and vision range of each other.ï¿½ A large male may consume up to 75 pounds of food every 24 hours.ï¿½ Their stomach is like a cow's stomach, having four chambers that require the animal to chew its cud, fist sized balls of unchewed food that are regurgitated. These animals are thought to be very intelligent.

ï¿½ Giraffe herd pausing at a water hole at night courtesy of Africam The birth of a giraffe is the most dangerous time in its life.ï¿½ Almost half of all newborns are killed by predators within the first few minutes.ï¿½ A newborn calf, weighing between 120-150 pounds and standing 6 feet tall, usually stands within several minutes and begins nursing within an hour.ï¿½ï¿½ The mother hides her calf for the first month trying to keep it safe from predators.ï¿½ Affection and protection is shown by the mother by rubbing, touching, sniffing, and licking her baby.ï¿½ The calves begin playing in "nursery" groups at about 2 months of age, learning necessary survival skills. Young giraffe nursing USATODAY.com - Horses have only one stomach 02/26/2002 - Updated 06:12 PM ET Horses have only one stomach Q: I know that cattle have four compartments in their stomachs. Since horses have the same diet do they also have four stomachs? Corel Horses have only one stomach but a long gut.

A: No, they only have one and a small one at that. Horses aren't ruminants like cattle, pronghorns, giraffes, okapis, deer, chevrotains, antelopes, sheep, and goats. Most of these animals do have four-chambered stomachs and can bolt their food down in a hurry. Later, perhaps when a threat is gone, they can regurgitate from the first chamber and chew their cud to break down the difficult-to-digest grass cell walls (cellulose). The other chambers digest the food further with the help of microorganisms that live in the stomach. Horses, on the other hand, have a small stomach (only 8.5 % of the whole digestive system, compared with 71 % for an ox) but a long digestive tract for breaking down cellulose. By the way, stomachs are really different among different species. Birds have a three-chambered stomach whereas a rodent has only one. Many rodents have to eat their food twice. A starfish can turn its stomach inside out and then push it part way out of its body to capture the soft contents of clams, for example.

Camels and llamas regurgitate and spit cud at enemies. (Answered by April Holladay, science correspondent, Feb. 27, 2002) More Wonderquest Giraffe | San Diego Zoo Animals & Plants San Diego Zoo Animals & Plants SPECIES: camelopardalis ABOUT Hello up there! Why do so many people look up to giraffes—besides the obvious reason? The long and short of it is that they are a wonderful example of nature’s creativity. Giraffes are the tallest land animals. A giraffe could look into a second-story window without even having to stand on its tiptoes! A giraffe's 6-foot (1.8-meter) neck weighs about 600 pounds (272 kilograms). The legs of a giraffe are also 6 feet (1.8 meters) long. The back legs look shorter than the front legs, but they are about the same length. A giraffe's heart is 2 feet (0.6 meters) long and weighs about 25 pounds (11 kilograms), and its lungs can hold 12 gallons (55 liters) of air! Its closest relative is the okapi.

Giraffes have a small hump on their back and have a spotted pattern similar to that of a leopard. For a long time people called the giraffe a “camel-leopard,” because they believed that it was a combination of a camel and a leopard. That's where the giraffe's species name camelopardalis comes from! Although a recent study of giraffe genetics published in the scientific journal Current Biology concluded that there are actually four distinct species of giraffes—said to be as different from each other as polar bears are from brown bears—one species is currently recognized, with nine subspecies. The subspecies have different coat patterns and live in different parts of Africa. Giraffe coat colors vary from light tan to practically black. The differences occur due to what the giraffes eat and where they live. Each individual giraffe’s markings are as individual as our fingerprints. Masai giraffes, from Kenya, have patterns that look like oak leaves. Uganda or Rothschild's giraffes sport large, brown splotches separated by thick, beige lines. The reticulated giraffe, found only in northern Kenya, has a dark coat with a seeming web of narrow white lines.

Some researchers now believe that reticulated giraffes are so genetically different from the other subspecies that they should be reclassified as a separate species. How many bones are there in a giraffe's neck? Just like humans, giraffes have seven neck vertebrae. For giraffes, however, each one can be over 10 inches (25.4 centimeters) long! Both male and female giraffes have two distinct, hair-covered horns called ossicones. Male giraffes use their horns to spar, throwing their neck against each other. As a male matures, calcium deposits begin to form on his skull to protect it when he head-butts with other males. These calcifications can be quite pronounced, giving the strange appearance of a three- to five-horned giraffe. Giraffes are so big that they really don't need to hide from predators. There is safety in numbers! It’s hard to pick out one giraffe from another when they form a tight group. Besides humans, only lions and crocodiles hunt them. If they have to, giraffes defend themselves with a deadly kick, karate-style.

Their speed, the way they move, and their body designs also help them to escape predators if they need to. Giraffes have a way of moving, or gait, in which both the front and back legs on one side move forward together, then the other two legs on the other side move forward. It’s called "pacing." Giraffes can run very fast—around 35 miles (56 kilometers) per hour for short distances. You might think watching out for lions and spending 16 to 20 hours a day eating would all weigh heavily on a giraffe. Surprisingly enough, giraffes only need 5 to 30 minutes of sleep in a 24-hour period! They often achieve that in quick naps that may last only a minute or two at a time. Giraffes can rest while standing, but they sometimes also lie down with their head resting on their rump. That’s a vulnerable position for a giraffe, though, so usually one herd member stays on guard. Many people think that giraffes have no voice, but they do make a variety of sounds, including moos, roars, snorts, hisses, and grunts.

They just very rarely do so. One sound giraffes make when they’re alarmed is a snort. Threats—such as lions nearby—may warrant a snort. Giraffes are often the early warning signal for other savanna animals: if a giraffe herd starts to run, everyone else does, too! Studies suggest giraffes vocalize below the level of human hearing and perhaps use this sound for long-distance communication. It’s easy to understand why giraffes top the list of so many people’s favorite animals. Their elegant stride, outrageous eyelashes, and calm expression give them an air of refinement. HABITAT AND DIET Blending right in: In a zoo, giraffes look conspicuous. But think of giraffes' presence in their African habitat, where their coat patterns actually serve as camouflage, blending with shadows and leaves. Giraffes are well adapted for living on the open, tree-dotted African plains. While other African herbivores compete for grass and small plants to eat, giraffes have the high branches with tender, young leaves all to themselves. It takes a lot of leaves to fuel such a large animal.

Giraffes may eat up to 75 pounds (34 kilograms) of food per day. They spend most of their day eating, because they get just a few leaves in each bite. Their favorite leaves are from acacia trees. These trees have long thorns that keep most animals from eating them. But those thorns don't stop the giraffes! They simply use their 18-inch (46-centimeter) tongue and prehensile lips to reach around the thorns. It is thought that the dark color of their tongue protects them from getting sunburned while reaching for leaves. Giraffes also have thick, sticky saliva that coats any thorns they might swallow. At the San Diego Zoo and the San Diego Zoo Safari Park, giraffes eat a variety of fresh acacia leaves hung high in artificial food “trees,” as well as hay, carrots, and low-starch, high-fiber biscuits. Giraffes are ruminants and have a stomach with four compartments that digests the leaves they eat. When giraffes aren't eating, they're chewing their cud.

After giraffes swallow the leaves the first time, a ball of leaves travels all the way back up the throat into the mouth for more grinding. Acacia leaves contain a lot of water, so giraffes can go a long time without drinking. When they do get thirsty, giraffes have to bend a long way down to drink from a lake or stream. When they're bent over, it is easier for a predator, like a crocodile, to grab hold of the giraffe. So, giraffes go to a watering hole together and take turns watching for predators. If water is easily available, like in zoos, they can drink 10 gallons (38 liters) a day. FAMILY LIFE When a giraffe baby, called a calf, is born, it comes into the world front feet first, followed by the head, neck, and shoulders. Its entry is like a slow-motion swan dive! Because the umbilical cord is only about 3 feet (1 meter) long, it breaks midway through the birth, allowing the newborn to drop to the ground. The fall and the landing don't hurt the calf, but they do cause it to take a big breath.

The calf can stand up and walk after about an hour, and within a week, it starts to sample vegetation. Sometimes the mother leaves the calf alone for most of the day. The youngster sits quietly until she returns. When a calf gets older, the mother leaves her youngster together with other calves in a "nursery." One of the moms stays to babysit while the others go out to eat and socialize. In the nursery, the calves develop physical and social skills through play. Under the watchful eye of the designated babysitter, the youngsters explore their surroundings throughout the day. The young giraffes can eat leaves at the age of four months, but continue to nurse until they are six to nine months old. AT THE ZOO Giraffes have drawn long looks from San Diego Zoo guests since 1938. Lofty and Patches were the Zoo’s first giraffes, arriving from Africa with much fanfare. Loading their crates off the ship and onto the truck for the long journey from New York to San Diego was quite a production, and upon their arrival here 10 days later, the giraffes refused to leave their traveling crate. Finally, someone offered them onions, and these veggies accomplished what nothing else could do.

To this day, onions serve as a special treat for our giraffes! The Zoo currently has a small herd of Masai giraffes that shares the exhibit in Urban Jungle with the much smaller Nubian Soemmering’s gazelles, adding interest for the animals and our guests. The Zoo has giraffe feeding opportunities. When you visit, be sure to check out the giraffe feeding times! The Safari Park is home to reticulated and Uganda giraffes; they share their field exhibits with a variety of antelope and rhinos, among other species, just as they might in the wild. Six-foot-tall (1.8 meters) feeding stations are ideal for giraffe calves—they can reach the food, but their antelope and rhino neighbors can’t. One of the Safari Park’s keepers says, “Telling the giraffes apart is like cloud watching. The longer you look at them, the more you’ll notice unique shapes in their spot pattern. And that’s how we tell them apart.” As the Safari Park has a large herd of Uganda giraffes (currently 16!), keepers photograph unusual characteristics of each one and keep the photos in a book in their keeper truck for easy reference.

Several years ago, it was suggested that, in their native ranges, many giraffe subspecies had begun to hybridize due to shrinking habitat—including the Uganda and reticulated subspecies, the two types we have at the Safari Park. Although some zoos chose to allow the two subspecies to crossbreed, we decided to keep ours separate. Now, the International Giraffe Group recommends not mixing the two subspecies; as Uganda giraffe populations dwindle, it’s important to preserve their genetic diversity in zoos. CONSERVATION In many African countries, giraffe populations are slowly decreasing because of habitat loss and the overgrazing of resources by livestock. As a result, the future of giraffes is dependent on the quality of the habitat that remains. Their numbers have decreased in the past century, and two giraffe subspecies, the West African or Nigerian giraffe Giraffa camelopardalis peralta and the Uganda or Rothschild’s giraffe G.c. rothschildi are endangered. While it has historically lived in western Kenya, Uganda, and southern Sudan, the Uganda giraffe has been almost totally eliminated from most of its former range and now survives in only a few small, isolated populations in Kenya and Uganda.

The Nigerian giraffe is found in just one area of Nigeria, and it is considered the rarest of the giraffes. The population of reticulated giraffes G.c. reticulata has dropped by an alarming 80 percent in just 10 years, most likely due to poaching. They are no match for humans with guns; giraffes are shot or snared for their meat, hide, bone marrow, and tail hair. The rest of the giraffe species have not become endangered for a number of reasons. Fortunately, Kenya is starting a giraffe conservation program for the three subspecies found there: reticulated, Uganda, and Masai giraffes G.c. tippelskirchi. San Diego Zoo Global supports a community conservation effort in northern Kenya that is finding ways for people and wildlife to live together. At the San Diego Zoo, we have a giraffe-feeding patio where high-fiber biscuits can be purchased and fed to the giraffes. The money raised through the sale of the giraffe biscuits funds the community conservation initiatives we support in Africa. You can help us bring giraffes back from the brink by supporting the San Diego Zoo Global Wildlife Conservancy .

Together we can save and protect wildlife around the globe. LIFE SPAN Sheep 101: Ruminants Source: Sheep Production Handbook, 2002. Young ruminants At birth, the lamb's rumen and reticulum are not yet functional. As lambs begin to nibble on dry feeds, these two compartments become innoculated with microorganisms. As the microbes multiply and begin to digest feed, they stimulate the growth and development of the rumen and reticulum. The lamb's rumen and reticulum are usually functional by the time the lamb is 50 to 60 days old. Because lambs are not born with a functioning rumen, supplemental feeds, such as creep feed, need to be highly digestible. Creep rations typicaly consist of feedstuffs that have been cracked, rolled, ground, or pelleted. Creep feeding enhances development of the rumen in the young lamb. The rumen in creep-fed lambs will develop quicker than the rumen in lambs that are fed strictly a forage diet.

Grazers by design Though ruminants can digest grain (starch), their more natural diet is forages: grass, weeds, browse, hay, and silage. If too much grain is consumed at one time or the diet is switched too quickly to grain, a large amount of lactic acid is produced in the rumen and the pH of the rumen drops. This can be a fatal condition to the ruminant animal. Grain must be introduced slowly to the diet of ruminants to give the rumen time to adjust, which it can easily do. Not too much grain Sheep "love" the taste of grain. It's like "candy" to them. They will overeat if grain consumption is not regulated. If grain is slowly introduced to the ruminant's diet, grain can be supplemented and in some cases replace some of the forage in the diet. Whole grain is better for sheep because it requires them to do their own grinding of the grain. Digestive upsets are less common with whole grain as compared to processed grains (ground, rolled, or cracked). Some forage should always be fed to ruminants to keep their rumens functioning properly and to keep them content.

Sometimes, if a sheep doesn't get enough forage in its diet, it will pick at another's wool. Read article The truth about feeding grain to sheep and goats=> Greenhouse gases An environmental impact of ruminant livestock production is that when ruminants belch (burp), they emit methane, one of the greenhouse gases. A small amount of methane is also produced by their manure. Methane accounts for only 8 percent of greenhouse gases. Ruminant livestock account for less than 40 percent of methane emission, and cattle account for 95 percent of that. Less methane is produced in intensive livestock systems as compared to more extensive, pastoral systems. Scientists are studying other ways to reduce methane production from ruminant livestock. For example, livestock fed certain plants produce less methane. Genetics also affects the amount of methane that a sheep emits. Australian scientists are testing a vaccine to reduce methane emissions. Giraffe Facts & Photos Giraffe Facts & Photos By Alina Bradford, Live Science Contributor | October 28, 2014 10:18pm ET MORE Giraffes tower over Africa's plains.

These tall animals are identified by their long necks, equally long and spindly legs, and spotted coats. Most giraffes have a tan, white or yellow coat that is spotted with brown, square shapes. Tallest animal Giraffes are the tallest living animals in the world, according to the Smithsonian National Zoological Park . A giraffe's neck alone is 6 feet (1.8 meters) long and weighs about 600 lbs. (272 kilograms). The animal's legs are also 6 feet long. In full, females grow up to 14 feet (4.3 m) tall and weigh up to 1,500 lbs. (680 kg), while males grow up to 18 feet (5.5 m) tall and weigh up to 3,000 lbs. (1,360 kg). With such a massive body, it makes sense that the giraffes' organs and other body parts are equally huge. Their tongues are a substantial 21 inches (53 centimeters) long, and their feet are 12 inches (30.5 cm) across.

According to the San Diego Zoo , a giraffe's heart is 2 feet (0.6 m) long and weighs about 25 lbs. (11 kg). Their lungs can hold 12 gallons (55 liters) of air. In comparison, the average total lung capacity for a human is 1.59 gallons (6 liters). Every giraffe has two hair-covered horns called ossicones. Male giraffes use their horns to playfully fight with one another. They also spar by swinging their heads at one another and entwining their necks, which is called "necking." [ Images: Animals' Dazzling Headgear ] Giraffes have unusually skinny legs for such large animals, but specialized bone structure allows them to support immense weight. Credit: EcoView/Fotolia Where do giraffes live? Giraffes live in savannas throughout Africa. They like semi-arid, open woodlands that have scattered trees and bushes, making the savannas perfect for these animals. Giraffes are so social that they don't have territories. A group of giraffes is aptly called a tower, according to the U.S. Geological Survey.

Towers typically have 12 to 15 members and are led by an older male. The other members in the tower are females, their young and young males. Giraffes only sleep around 20 minutes or less per day, according to PBS Nature. Staying awake most of the time allows them to be constantly on alert for predators. They usually get their sleep in quick power naps that last just a couple of minutes. Diet Giraffes are herbivores, which means they eat only plants. Their long necks allow them to reach leaves, buds and branches high up in mimosa and acacia trees. They can eat hundreds of pounds of leaves per week, according to National Geographic . Though these animals eat a lot, giraffes can go without drinking for weeks at a time. They get most of their moisture from the vegetation they eat. The new Rothschild's giraffe calf takes her first steps. Credit: Belfast Zoo. Offspring As in cattle, female giraffes are called cows, while the males are called bulls. After mating, the cow will have a gestation period of around 14 months.

During birth, the calf will drop to the ground, since mother giraffes give birth standing up. The fall can be as far as 5 feet (1.5 m), according to National Geographic. New calves are quite large, at 6 feet tall (1.8 m), 100 to 150 lbs. (45 to 68 kg), according to the San Diego Zoo. They are also agile. At just an hour after birth, they can stand up and walk around. Giraffe mothers often take turns watching over the calves. Sometimes, though, the mother giraffe will leave the calf by itself. When this happens, the infant will lie down and wait for its mother to return. At 3 to 6 years old, calves are fully mature. The animals can live up to 20 years. Classification/taxonomy According to the Giraffe Conservation Foundation (GCF), it is generally accepted that there is one species of giraffe, which has nine subspecies. However, the Integrated Taxonomic Information System (ITIS) lists only six, and the International Union for Conservation of Nature (IUCN) only recognizes two.

Recent genetic analysis indicates some of these subspecies may be separate species, according to the GCF. The taxonomy of giraffes, according to ITIS, is: Kingdom: Animalia Giraffa camelopardalis camelopardalis (Nubian giraffe) Giraffa camelopardalis giraffa (South African giraffe or cape giraffe) Giraffa camelopardalis reticulata (reticulated giraffe) Giraffa camelopardalis rothschildi (Ugandan giraffe or Rothschild's giraffe) Giraffa camelopardalis thornicrofti (Thornicroft's giraffe) Giraffa camelopardalis tippelskirchi (Masai giraffe) In addition, GCF lists Giraffa camelopardalis angolensis (Angolan giraffe or smokey giraffe), Giraffa camelopardalis antiquorum (Kordofan giraffe) and Giraffa camelopardalis peralta (Niger giraffe, Nigerian giraffe or West African giraffe). Conservation status Giraffes crossing the road, safari, Kenya, East Africa, Ol Pejeta conservancy.

Credit: Stock.xchng Giraffes as a whole are not endangered, and are listed as "least concern" by the IUCN's Red List of Threatened Species . Although not threatened by extinction, the giraffe population is less than 80,000 and decreasing, but the exact numbers are unclear, according to the Red List. The Nigerian giraffe and Rothschild's giraffe subspecies, however, are listed as endangered. The IUCN says there were fewer than 200 Nigerian giraffe individuals at last count in 2008, although numbers were increasing due to conservation programs. Estimates in 2010 put the population of Rothschild's giraffes at well below 2,500 mature individuals. The IUCN says the subspecies is potentially close to meeting the threshold for being listed as "critically endangered." Giraffe populations are challenged because of poaching and shrinking habitat. The animals' tails are made into good-luck bracelets, fly whisks and thread for stringing beads, according to the African Wildlife Foundation . As agricultural settlement expands, the giraffe's main source of food, the acacia tree, is being cut down.

Other facts Just like human fingerprints and zebra stripes, the coat pattern of a giraffe is unique to that animal. The pattern and the small hump on a giraffe's back are similar to those of a leopard. Years ago, many people thought the giraffe was a combination of a camel and a leopard, and they called these animals "camel-leopards." You will often see giraffes walking around with birds on their backs. These birds are called tickbirds. They eat bugs that live in the giraffe's coat and alert the animals to danger by chirping loudly. Even if you spent a lot of time with giraffes, you would never hear them make a noise. This is because giraffes communicate using noises that are too low for humans to hear, according to PBS Nature. Thanks to their long legs, giraffes are very fast. They can run 35 mph (56 km/h) in short bursts and run for longer stretches at 10 mph (16 km/h), according to National Geographic.

Giraffes are even-toed ungulates, which means they have two weight-bearing hooves on each foot, and are in the order Artiodactyla, which also includes antelopes, cattle, goats, sheep, caribou, moose, hippos and pigs. Additional resources How many stomachs does a giraffe have | How many stomachs does a giraffe have How many stomachs does a giraffe have? The giraffe is a ruminant, much like a cow, possessing a stomach with four distinct chambers. After a giraffe eats vegetation and swallows it, the food goes into the first chamber before making its... Read More » Top Q&A For: How many stomachs does a giraffe have How many knees does a giraffe have? Giraffes have two knees, both of which are located on their front legs. Their forelegs are about 10 percent longer than their rear legs, giving giraffes their characteristic gait and pace as they ... Read More » How many vertebrae does a giraffe have in its neck? Because they are known for long necks, many people assume that giraffes have more vertebrae than humans.

The truth is that giraffes have just seven vertebrae in their necks, just like people. The d... Read More » How many bones does a giraffe have in its body? An adult giraffe has 207 bones. An adult human has 206 bones. A giraffe is a mammal and, like a human, has seven bones in its neck. The difference is that the giraffe's neck bones are much longer.S... Read More » How many neck vertebrae does a giraffe have? A giraffe has seven neck vertebrae, the same amount of vertebrae that a human has. However in a giraffe, each vertebrae is about 10 inches long. This makes the giraffe very tall, the tallest animal... Read More »

Question: How many chambers does a giraffe have in its stomach?
Answer: Four