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'''Kaniner'' er små pattedyr i familen [[Leporidae]] ([[hare]]r og Kaniner) fra ordnen [[støttetandede]]. Kaniner adskiller sig fra harer ved at være skovlevende eller gravende dyr, Der ikke løber særlig godt over lange stræk.
'''Kaniner'' er små pattedyr i familen [[Leporidae]] ([[hare]]r og Kaniner) fra ordnen [[støttetandede]]. Kaniner adskiller sig fra harer ved at være skovlevende eller gravende dyr, der ikke løber særlig godt over lange stræk.


==Biologi==
==Biologi==




==Diet and eating habits==
==Diet and eating habits==

Versionen fra 23. mar. 2008, 12:00

Kanin
Vildkanin ved Rindby Strand, Fanø Foto: Malene Thyssen, 2002
Vildkanin ved Rindby Strand, Fanø
Foto: Malene Thyssen, 2002
Videnskabelig klassifikation
Rige Animalia (Dyr)
Række Chordata (Chordater)
Klasse Mammalia (Pattedyr)
Orden Lagomorpha
(Støttetandede)
Familie Leporidae
(delvis)
Hjælp til læsning af taksobokse


'Kaniner er små pattedyr i familen Leporidae (harer og Kaniner) fra ordnen støttetandede. Kaniner adskiller sig fra harer ved at være skovlevende eller gravende dyr, der ikke løber særlig godt over lange stræk.

Biologi

Diet and eating habits

Rabbits are herbivores who feed by grazing on grass, forbs, and leafy weeds. In addition, their diet contains large amounts of cellulose, which is hard to digest. Rabbits solve this problem by passing two distinctive types of feces: hard droppings and soft black viscous pellets, the latter of which are immediately eaten. Rabbits reingest their own droppings (rather than chewing the cud as do cows and many other herbivores) in order to fully digest their food and extract sufficient nutrients. [1] [2]

Rabbits graze heavily and rapidly for roughly the first half hour of a grazing period (usually in the late afternoon), followed by about half an hour of more selective feeding. In this time, the rabbit will also excrete many hard faecal pellets, being waste pellets that will not be reingested. If the environment is relatively non-threatening, the rabbit will remain outdoors for many hours, grazing at intervals. While out of the burrow, the rabbit will occasionally reingest its soft, partially digested pellets; this is rarely observed, since the pellets are reingested as they are produced. Reingestion is most common within the burrow between 8 o'clock in the morning and 5 o'clock in the evening, being carried out intermittently within that period.

Hard pellets are made up of hay-like fragments of plant cuticle and stalk, being the final waste product after redigestion of soft pellets. These are only released outside the burrow and are not reingested. Soft pellets are usually produced several hours after grazing, after the hard pellets have all been excreted. They are made up of micro-organisms and undigested plant cell walls.

The chewed plant material collects in the large cecum, a secondary chamber between the large and small intestine containing large quantities of symbiotic bacteria that aid in the digestion of cellulose and also produce certain B vitamins. The pellets are about 56% bacteria by dry weight, largely accounting for the pellets being 24.4% protein on average. These pellets remain intact for up to six hours in the stomach, the bacteria within continuing to digest the plant carbohydrates. The soft feces form here and contain up to five times the vitamins of hard feces. After being excreted, they are eaten whole by the rabbit and redigested in a special part of the stomach. This double-digestion process enables rabbits to utilize nutrients that they may have missed during the first passage through the gut and thus ensures that maximum nutrition is derived from the food they eat. [3] This process serves the same purpose within the rabbit as rumination does in cattle and sheep. [4]

Rabbits are incapable of vomiting due to the physiology of their digestive system.[5]

Behavior

While the European rabbit is the best-known species, it is probably also the least typical, as there is considerable variability in the natural history of rabbits. Many rabbits dig burrows, but cottontails and hispid hares do not. The European rabbit constructs the most extensive burrow systems, called warrens. Nonburrowing rabbits make surface nests called forms, generally under dense protective cover. The European rabbit occupies open landscapes such as fields, parks, and gardens, although it has colonized habitats from stony deserts to subalpine valleys. It is the most social rabbit, sometimes forming groups in warrens of up to 20 individuals. However, even in European rabbits social behaviour can be quite flexible, depending on habitat and other local conditions, so that at times the primary social unit is a territorial breeding pair. Most rabbits are relatively solitary and sometimes territorial, coming together only to breed or occasionally to forage in small groups. During territorial disputes rabbits will sometimes “box,” using their front limbs. Rabbits are active throughout the year; no species is known to hibernate. Rabbits are generally nocturnal, and they also are relatively silent. Other than loud screams when frightened or caught by a predator, the only auditory signal known for most species is a loud foot thump made to indicate alarm or aggression. Notable exceptions are the Amami rabbit and the volcano rabbit of Mexico, which both utter a variety of calls. [3]

Instead of sound, scent seems to play a predominant role in the communication systems of most rabbits; they possess well-developed glands throughout their body and rub them on fixed objects to convey group identity, sex, age, social and reproductive status, and territory ownership. Urine is also used in chemical communication. When danger is perceived, the general tendency of rabbits is to freeze and hide under cover. If chased by a predator, they engage in quick, irregular movement, designed more to evade and confuse than to outdistance a pursuer. Skeletal adaptations such as long hind limbs and a strengthened pelvic girdle enable their agility and speed (up to 80 km [50 miles] per hour). [3]

Reproduction

Most rabbits produce many offspring (kittens) each year, although scarcity of resources may cause this potential to be suppressed. A combination of factors allows the high rates of reproduction commonly associated with rabbits. Rabbits generally are able to breed at a young age, and many regularly conceive litters of up to seven young, often doing so four or five times a year due to the fact that a rabbit's gestation period is only 28 to 31 days.[6]. In addition, females (does) exhibit induced ovulation, their ovaries releasing eggs in response to copulation rather than according to a regular cycle. They can also undergo postpartum estrus, conceiving immediately after a litter has been born. [3]

Newborn rabbits are naked, blind, and helpless at birth (altricial). Mothers are remarkably inattentive to their young and are almost absentee parents, commonly nursing their young only once per day and for just a few minutes. To overcome this lack of attention, the milk of rabbits is highly nutritious and among the richest of that of all mammals. The young grow rapidly, and most are weaned in about a month. Males (bucks) do not assist in rearing the kittens. [3]

Differences from hares

Hovedartikel: Hare.

Rabbits are clearly distinguished from hares in that rabbits are altricial, having young that are born blind and hairless. In contrast, hares are generally born with hair and are able to see (precocial). All rabbits (except the cottontail rabbit) live underground in burrows or warrens, while hares live in simple nests above the ground (as does the cottontail rabbit), and usually do not live in groups. Hares are generally larger than rabbits, with longer ears, and have black markings on their fur. Hares have not been domesticated, while rabbits are often kept as house pets. In gardens, they are typically kept in hutches –small, wooden, house-like boxes– that protect the rabbits from the environment and predators.

Rabbits as pets

Hovedartikel: House rabbit.

Rabbits kept in a home as pets for companionship are referred to as house rabbits. They typically have an indoor pen and a rabbit-safe place to run and exercise, such as a living or family room. Rabbits are easily trained to use a litter box and can learn to come when called. Their diet typically consists of unlimited Timothy hay, a small amount of pellets, and fresh vegetables. House rabbits are quiet pets, but are unsuitable for households with small children as they are easily frightened by loud noises and can be harmed by mishandling.

Domestic rabbits that are not house rabbits also often serve as companions for their owners, typically living in an easily accessible hutch outside the home.

Rabbits as food and clothing

Skabelon:Seealso

Leporids such as European rabbits and hares are a food meat in Europe, South America, North America, some parts of the Middle East, and China, among other places.

Rabbit is still commonly sold in UK butchers and markets, although not frequently in supermarkets. At farmers markets and the famous Borough Market in London, rabbits will be displayed dead and hanging unbutchered in the traditional style next to braces of Pheasant and other small game. Rabbit meat was once commonly sold in Sydney, Australia, the sellers of which giving the name to the rugby league team the South Sydney Rabbitohs, but quickly became unpopular after the disease myxomatosis was introduced in an attempt to wipe out the feral rabbit population (see also Rabbits in Australia).

When used for food, rabbits are both hunted and bred for meat. Snares or guns along with dogs are usually employed when catching wild rabbits for food. In many regions, rabbits are also bred for meat, a practice called cuniculture. Rabbits can then be killed by hitting the back of their heads, a practice from which the term rabbit punch is derived. Rabbit meat is a source of high quality protein. It can be used in most ways chicken meat is used. Rabbit meat is leaner than beef, pork, and chicken meat. Rabbit products are generally labeled in three ways, the first being Fryer. This is a young rabbit between 1½ and 3½ pounds and up to 12 weeks in age. This type of meat is tender and fine grained. The next product is a Roaster; they are usually over 4 pounds and over 8 months in age. The flesh is firm and coarse grained and less tender than a fryer. Then there are giblets which include the liver and heart. One of the most common types of rabbit to be bred for meat is New Zealand white rabbit.

There are several health issues associated with the use of rabbits for meat, one of which is Tularemia or Rabbit Fever. Another is so-called rabbit starvation, due most likely to essential amino acid deficiencies in rabbit meat and synthesis limitations in human beings.

Rabbits are a favorite food item of large pythons, such as Burmese pythons and reticulated pythons, both in the wild, as well as pet pythons. A typical diet for example, for a pet Burmese python, is a rabbit once a week.[kilde mangler]

Rabbit pelts are sometimes used in for clothing and accessories, such as scarves or hats. Rabbits are very good producers of manure; additionally, their urine, being high in nitrogen, makes lemon trees very productive. Their milk may also be of great medicinal or nutritional benefit due to its high protein content (see links below).

Environmental problems

A European Rabbit afflicted by Myxomatosis in England.

Skabelon:Seealso Rabbits have been a source of environmental problems when introduced into the wild by humans. As a result of their appetites, and the rate at which they breed, wild rabbit depredation can be problematic for agriculture. Gassing, barriers (fences), shooting, snaring, and ferreting have been used to control rabbit populations, but the most effective measures are diseases such as myxomatosis (myxo or mixi, colloquially) and calicivirus. In Europe, where rabbits are farmed on a large scale, they are protected against myxomatosis and calicivirus with a genetically modified virus. The virus was developed in Spain, and is beneficial to rabbit farmers. If it were to make its way into wild populations in areas such as Australia, it could create a population boom, as those diseases are the most serious threats to rabbit survival. Rabbits in Australia are considered to be such a pest that land owners are legally obliged to control them.

Classifications

Rabbits and hares were formerly classified in the order Rodentia (rodent) until 1912, when they were moved into a new order Lagomorpha. This order also includes pikas.

Order Lagomorpha

Naming

Rabbits are often known affectionately by the pet name bunny or bunny rabbit, especially when referring to young, domesticated rabbits. Originally, the word for an adult rabbit was coney or cony, while rabbit referred to the young animals. Coney was abandoned as a term for the animal after it was co-opted in the eighteenth century as a synonym for the word cunt, widely considered vulgar.[7] More recently, the term kit has been used to refer to a young rabbit. A group of young rabbits is referred to as a kindle. Young hares are called leverets, and this term is sometimes informally applied to any young rabbit. Male rabbits are called bucks and females does. A group of rabbits or hares are often called a fluffle in parts of Northern Canada.

Rabbits in culture and literature

Skabelon:Seealso

Rabbit and Acorn Jay Birds, a Song Dynasty era painting by Chinese artist Cui Bai, painted in 1061 AD.

Rabbits are often used as a symbol of fertility or rebirth, and have long been associated with spring and Easter as the Easter Bunny. The species' role as a prey animal also lends itself as a symbol of innocence, another Easter connotation. Additionally, rabbits are often used as symbols of playful sexuality, which also relates to the human perception of innocence, as well as its reputation as a prolific breeder.Skabelon:See

Folklore and mythology

The rabbit often appears in folklore as the trickster archetype, as he uses his cunning to outwit his enemies.

  • A Korean myth similar to the Japanese counterpart also presents rabbits living on the moon making rice cakes (Tteok in Korean), although not specified as mochi (rice cakes that have sweet red bean paste fillings).
  • In Native American Ojibwe mythology, Nanabozho, or Great Rabbit, is an important deity related to the creation of the world.
  • In Central Africa "Kalulu" the rabbit is widely known as a tricky character, getting the better of bargains. [kilde mangler]
  • In Jewish folklore, rabbits (shfanim) are associated with cowardice.

On the Isle of Portland in Dorset, UK, the rabbit is said to be unlucky and speaking its name can cause upset with older residents. This is thought to date back to early times in the quarrying industry, where piles of extracted stone (not fit for sale) were built into tall rough walls (to save space) directly behind the working quarry face; the rabbit's natural tendency to burrow would weaken these "walls" and cause collapse, often resulting in injuries or even death.

The name rabbit is often substituted with words such as “long ears” or “underground mutton”, so as not to have to say the actual word and bring bad luck to oneself. It is said that a public house (on the island) can be cleared of people by calling out the word rabbit and while this was very true in the past, it has gradually become more fable than fact over the past 50 years.

Other fictional rabbits

The rabbit as trickster appears in American popular culture; for example the Br'er Rabbit character from African-American folktales and Disney animation; and the Warner Brothers cartoon character Bugs Bunny. Anthropomorphized rabbits have appeared in a host of works of film, literature, and technology, notably the White Rabbit and the March Hare in Lewis Carroll's Alice's Adventures in Wonderland; in the popular novel Watership Down, by Richard Adams; Cream the Rabbit, daughter to Vanilla the Rabbit, from the Sonic the Hedgehog video game series; and in Beatrix Potter's Peter Rabbit stories. Also they appear as Rabbids in the Ubisoft game Rayman Raving Rabbids and in the movie Monty Python and the Holy Grail, there is the Killer Rabbit of Caerbannog which is killed by the Holy Hand Grenade of Antioch, and rabbits are featured in both The Goodies episodes (Invasion of the Moon Creatures and Animals). Rabbits are also the subject of one of the first children's stories The Velveteen Rabbit by Margery Williams, as well as the Little Golden Books story "The Lively LIttle Rabbit". The Pokémon franchise has also released two new rabbit Pokémon, Buneary and its evolution Lopunny.

Urban legends

Hovedartikel: Rabbit test.

It was commonly believed that pregnancy tests were based on the idea that a rabbit would die if injected with a pregnant woman's urine. This is not true. However, in the 1920s it was discovered that if the urine contained the hCG, a hormone found in the bodies of pregnant women, the rabbit would display ovarian changes. The rabbit would then be killed to have its ovaries inspected, but the death of the rabbit was not the indicator of the results. Later revisions of the test allowed technicians to inspect the ovaries without killing the animal. A similar test involved injecting Xenopus frogs to make them lay eggs, but animal assays for pregnancy have been made obsolete by faster, cheaper, and simpler modern methods.

Skabelon:North American Game Skabelon:English Game

References

  1. ^ rabbits
  2. ^ rabbits general
  3. ^ a b c d e Fodnotefejl: Ugyldigt <ref>-tag; ingen tekst er angivet for referencer med navnet Encyclopædia Britannica
  4. ^ The Private Life of the Rabbit, R. M. Lockley, 1964. Chapter 10.
  5. ^ "True or False? Rabbits are physically incapable of vomiting. (Answer to Pop Quiz)".
  6. ^ "What's the gestation period of a rabbit? (Answer to Pop Quiz)".
  7. ^ "Online Etymology Dictionary - definition of coney". long-eared rabbit

See also

External links

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