Guinea pig

This is an old revision of this page, as edited by Chubbles (talk | contribs) at 02:25, 26 March 2007. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Revision as of 02:25, 26 March 2007 by Chubbles (talk | contribs)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)

Template:Two other uses

Domestic Guinea Pig

Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Family:	Caviidae
Subfamily:	Caviinae
Genus:	Cavia
Species:	C. porcellus
Binomial name
*Cavia porcellus* (Linnaeus, 1758)

Guinea pigs (also called cavies) are rodents belonging to the family Caviidae and the genus Cavia, originally native to the Andes. Despite their common name, the animals are not pigs, nor do they come from Guinea. The guinea pig plays an important role in the folk culture of indigenous South Americans, especially as a food source. In Western societies, the guinea pig has enjoyed widespread popularity as a household pet since its introduction by European traders in the sixteenth century. More recently, organizations devoted to competitive breeding of guinea pigs have been formed worldwide.

"Guinea pig" is also used as a by-word for a subject of scientific experimentation. The animals were frequently used in scientific contexts in the nineteenth and twentieth centuries, but have since been largely replaced by other rodents, such as mice and rats.

History

The common guinea pig was first domesticated about 5000 BC for food by mountain tribes in the Andean region of South America, (present-day Ecuador, Peru and Bolivia). They continue to be a food source in the region, subsisting off a family's vegetable scraps as a pet. Folklore traditions involving guinea pigs abound; they are exchanged as gifts, used in customary social and religious ceremonies, and are frequently referenced in spoken metaphors. They also play a role in some traditional healing rituals by folk doctors or curanderos. They are rubbed against the bodies of the sick, and are seen as a medium through which supernatural healing occurs. Guinea pigs are called quwi in Quechua and cuy or cuyo (pl. cuyes, cuyos) in the Spanish of Ecuador, Peru and Bolivia.

Dutch and English traders brought guinea pigs to Europe, where they quickly became popular as exotic pets among the upper classes and royalty, including Queen Elizabeth I. The guinea pig was first described in the West in 1554 by the Swiss naturalist Konrad Gesner. Its official binomial scientific name, Cavia porcellus, was conferred by Linnaeus in 1758.

Name

How the animals came to be thought of as "pigs" is not clear. They are built somewhat like a pig, with a large head relative to the body, a stout neck, and a rounded rump with no tail of any consequence; some of the sounds they emit are very similar to those made by pigs, and they also spend a large amount of time eating. They can survive for long periods of time in small quarters, like a 'pig pen', and were thus easily transported on ships to Europe.

The animal's name carries connotations of it being a pig in many languages. The German word for them is Meerschweinchen, literally "little sea pigs" (sailing ships stopping to re-provision in the New World would pick up stores of guinea pigs, which provided an easily transportable source of fresh meat; Meerschwein = porpoise, another food source for sailors). The Welsh term is mochyn cwta ('little pig'), the French Cochon d'Inde (Indian pig); the Dutch used to call it guinees biggetje (Guinean piglet). In Italian the term is either Porcellino d'India (Little Indian Pig) or Cavia Peruviana (Peruvian Cavy). This is not universal; for example, the common Spanish word is conejillo de Indias (little rabbit of India / the Indies). The scientific name of the common species is Cavia porcellus, with porcellus being Latin for "little pig". Cavia is derived from Portuguese çavia (now savia) from the Tupi word saujá, meaning rat.

The origin of "guinea" in "guinea pig" is even harder to explain. One theory is that the animals were brought to Europe by way of Guinea, leading people to think they had originated there. "Guinea" was also frequently used in English to refer generally to any far-off, unknown country, and so the name may simply be a colorful reference to the animal's foreignness. Another theory suggests the "guinea" in the name is a corruption of "Guiana", an area in South America, though the animals are not native to that region. A common misconception is that they were so named because they were sold as the closest thing to a pig one could get for a guinea; this theory is untenable, because the guinea was first struck in England in 1663, and William Harvey is known to have used the term "Ginny-pig" as early as 1653. Others believe "guinea" may be an alteration of the word coney; guinea pigs were referred to as "pig coneys" in Edward Topsell's 1607 treatise on quadrupeds.

Traits and environment

Guinea pigs are large for rodents, weighing between 0.5 and 1.5 kg (1–3 pounds), and measuring 25–40 cm (10–15 inches) long. They typically live an average of four to five years, and occasionally as long as eight years. According to the 1997 Guinness Book of Records the longest living guinea pig survived 15 years. They are social, living in the wild in small groups which consist of sows (females), a boar (male), and the young (which in a break with the preceding porcine nomenclature are called pups). Domesticated guinea pigs thrive in groups of two or more; groups of sows, or groups of one or more sows and a neutered boar are common combinations. Groups of boars may also get along, provided their cage has enough space, they are not introduced to a female, and proper introduction techniques are employed.

In the wild, guinea pigs are found on grassy plains and occupy an ecological niche similar to that of the cow. They move together in groups (herds) eating grass or other vegetation, and do not store food. While they do not burrow, they frequently seek shelter in the burrows of other animals, as well as in crevices and tunnels formed by vegetation. They are crepuscular, tending to be most active during dawn and dusk, when it is harder for predators to spot them. Domestic guinea pigs have developed a different rhythm, and have longer periods of activity followed by short periods of sleep in between. Activity is scattered randomly over the 24 hours of the day; aside from avoidance of intense light, no regular circadian patterns are apparent.

Domestic guinea pigs generally live in cages, though some owners of large numbers of guinea pigs will dedicate entire rooms to their pets. Cages with wire mesh floors can cause injury and may be associated with a foot infection commonly known as bumblefoot (ulcerative pododermatitis). Cages are often lined with wood shavings or a similar material. Bedding made from red cedar and pine, both softwoods, were commonly used in past decades but are now believed to contain harmful phenols (aromatic hydrocarbons) and oils. Safer beddings include those made from hardwoods (such as aspen or hemp); paper products and corn cob are other alternatives. "Cubes and Coroplast" (or C&C) style cages are now a common choice.

Unlike many rodents such as mice, rats, or squirrels, guinea pigs cannot climb, and are not particularly agile. However, they startle extremely easily, and will run for cover with rapid, darting motions when they sense danger. When excited, guinea pigs may repeatedly perform little jumps in the air (known as "popcorning").

Guinea pigs can learn complex paths to food. They can accurately remember the learned path for weeks and months. Their strongest and overwhelming problem solving strategy is moving.

Guinea pigs are very vocal animals. Vocalization is the primary means of communication between members of the species. Some sounds are:

Wheek or Whistle- A loud noise that is essentially onomatopoetic. An expression of general excitement, it may occur in response to the presence of its owner or to food replenishment. It is sometimes used to find other guinea pigs if they are in a run. If a guinea pig is lost, it may wheek for assistance.
Bubbling, or Purring - This rather pleasant sound is made when the guinea pig is enjoying itself, when being petted or held. They may also make this sound when grooming, crawling around to investigate a new place, or when given food.
Rumbling - This sound is related to guinea pig dominance. It can also come as a response to comfort or contentment. Whilst courting, a male usually purrs deeply, while swaying from side to side, nearly lifting the rear feet.
Chutting and Whining - these are sounds made in pursuit situations, by the pursuer and pursuee, respectively.
Chattering - This sound is made by rapidly gnashing the teeth together, and is generally a sign of warning. Guinea pigs tend to raise their heads when making this sound.
Squealing or Shrieking - a high-pitched sound of discontent, in response to pain or danger.
Chirping - This less-common sound seems to be related to stress.

Breeding

The guinea pig's gestation period lasts from 59-72 days, with an average of 63-68 days. Pups are already well developed at birth, including fur, teeth, claws and full eyesight, when they are born. The young are mobile from birth, and depending on the environment, will usually venture outdoors within a week. Pups begin eating solid food after a couple of days, though continue to suckle also. Litters generally yield 1-6 young, with an average of 3. In smaller litters, difficulties may occur during labour, due to over-sized pups. Large litters may result in higher incidences of stillbirth, but because the pups are delivered at an advanced stage of development, lack of access to mother's milk has little effect on the mortality rate of newborns. Cohabitating females may assist in mothering duties if lactating.

Because of the long gestation period and the large size of the pups, pregnant females may become large and eggplant-shaped (aubergine), although the change in size and shape varies among individual animals. Breeding males produce a strong musk that smells much like beeswax.

Sexing of guinea pigs can be difficult, as males and females do not differ in external appearance apart from general size, and the position of the anus is very close to the genitals in both sexes. Female genitals are distinguished a Y-shaped configuration formed from a vaginal flap; while the male genitals may look similar with the penis and anus forming a like shape, the penis will protrude if pressure is applied to the surrounding hair. The male's testes may also be visible externally from scrotal swelling.

Males reach sexual maturity at 3-5 weeks; females can be fertile as early as four weeks and can carry litters before they themselves are adults. Females that have never been bred commonly develop irreversible fusing of the pubic symphysis, a joint in the pelvis, after six months of age. If they become pregnant after this has happened, the birth canal will not widen sufficiently, this may lead to dystocia and death as they attempt to give birth.Females can become pregnant in 6-48 hours after giving birth, and it is not healthy for a female to be in virtually a constant state of pregnancy.

Toxemia of pregnancy is common and kills many pregnant females. Signs of toxemia include anorexia, lack of energy, excessive salivation, and a ketone breath odor, and in advanced cases seizures and death. Pregnancy toxemia appears to be most common in hot climates. Other serious complications of pregnancy can include a prolapsed uterus, hypocalcemia, and mastitis.

Diet

Grass is the guinea pig's natural diet. Their molars are particularly suited for grinding plant matter, and grow continuously throughout the animal's life. Most grass-eating mammals are quite large and have a long digestive tract; while guinea pigs have much longer colons than most rodents, they must also supplement their diet by practicing coprophagy, the eating of their own feces. However, they do not consume their feces indiscriminately. They produce special soft pellets, called "cecotropes", which recycle B vitamins, fiber, and bacteria required for proper digestion; these are eaten directly from the anus, unless the guinea pig is pregnant or obese. They share this behaviour with rabbits.

Guinea pigs benefit from feeding on grass hay, such as timothy hay, in addition to food pellets; alfalfa is also a popular food choice. Imbalanced diets have been associated with muscular dystrophy, metastatic calcification, difficulties with pregnancy, vitamin deficiencies, and teeth problems. Guinea pigs tend to be fickle eaters, having learned early in life what is and is not appropriate to consume, and their habits are difficult to change after maturity. They do not respond well to sudden changes in diet; they may stop eating and starve rather than accepting new food types. A constant supply of hay or other food is generally recommended, as guinea pigs feed continuously and may develop habits such as chewing on their own hair if food is not present.

Like humans, but unlike most other mammals, guinea pigs cannot synthesize their own vitamin C and must obtain this vital nutrient from food. If guinea pigs do not ingest enough vitamin C, they can suffer from scurvy and ultimately die. Guinea pigs require about 10 mg of vitamin C daily (20mg if pregnant), which can be obtained through fresh, raw fruits and vegetables or through supplements fed to domestic animals.

A number of plants are poisonous to guinea pigs, including bracken, bryony, buttercup, charlock, deadly nightshade, foxglove, hellebore, hemlock, lily of the valley, mayweed, monkshood, privet, ragwort, rhubarb, speedwell, toadflax and wild celery. Additionally, any plant which grows from a bulb (e.g., tulip and onion) is normally considered poisonous. Guinea pigs will also chew on cloth, paper, plastic, and rubber.

Health

A red and white texel with Torticollis, or wry neck

Common ailments in domestic guinea pigs include respiratory infections, diarrhea, scurvy (vitamin C deficiency, typically characterized by sluggishness), abscesses due to infection (often in the neck, due to hay embedded in the throat, or from external scratches), and infections by lice, mites or fungus.

Mange mites (Trixacarus caviae) are a common cause of fur loss, whose symptoms also may include excessive scratching, unusually aggressive behavior when touched (due to pain), and in some instances, seizures. Guinea pigs may also suffer from "running lice" (Gliricola porcelli), a small white insect which can be seen running through fur. Other causes of fur loss can be due to hormonal upsets caused by underlying medical conditions such as ovarian cysts.

While it is normal for guinea pigs to sneeze periodically, frequent sneezing be a symptom of pneumonia, especially in response to atmospheric changes. Pneumonia may also be accompanied by torticollis and can be fatal.

Guinea pigs are "prey animals" whose survival instinct is to mask pain and signs of illness, and many times signs of illness may not be apparent until a problem is severe or in its advanced stages.

Domestic guinea pigs

Main article: Domestic varieties of guinea pigs

Guinea pigs are widely considered to be good pets. If handled early in their life by caring owners, they become very amenable to being picked up and carried. Guinea pigs who become familiar with their human seem to consider them part of their herd, and become distraught when separated for long periods. Because of this widespread popularity in domestic life, and especially because of their popularity in households with children, guinea pigs have often, in recent years, been featured in popular culture.

Domesticated guinea pigs come in many breeds which have been developed since their arrival in Europe and North America. These varieties vary widely in hair and color composition.

All over the world there are Cavy Clubs and Associations dedicated to the showing and breeding of guinea pigs. The American Cavy Breeders Association, an adjunct to the American Rabbit Breeders Association, is the governing body in the United States and Canada. Each club publishes its own Standard of Perfection and determines which breeds are eligible for showing.

Guinea pigs in scientific research

Guinea pig experimentation dates back at least to the eighteenth century. In 1780, Antoine Lavoisier used a guinea pig in his experiments with the calorimeter, a device used to measure heat production. The heat from the guinea pig's respiration melted snow surrounding the calorimeter, showing that respiratory gas exchange is a combustion, similar to a candle burning.

In English, the term guinea pig is commonly used as a metaphor for a subject of scientific experimentation. This dates back to the early twentieth century; the OED notes its first usage in this capacity in 1913. In 1933, Consumers' Research founders F. J. Schlink and Arthur Kallet wrote a book entitled 100,000,000 Guinea Pigs, extending the metaphor to consumer society. The book became a national bestseller in the United States, thus further popularizing the term, and spurred the growth of the consumer protection movement.

Guinea pigs were popular laboratory animals into the later twentieth century, but are now less commonly used; about 2.5 million guinea pigs were used annually in the U.S. for research in the 1960s, but that total decreased to approximately 375,000 by the mid-1990s. They now constitute approximately 2% of the current total of laboratory animals. Complement, an important component for serology, was first isolated from the blood of guinea pigs. In the past they were used to isolate different bacterial strains, but in modern labs they have been replaced by mice and rats, which reproduce more quickly and which are more completely characterized genetically.

Because guinea pigs are one of the few animals which, like humans, cannot synthesize Vitamin C but must obtain it from diet, they have been used for research on diseases such as scurvy. Guinea pigs also have an unusual insulin mutation, and they are a suitable species for the generation of anti-insulin antibodies. Guinea pigs have been identified as model animals for the study of juvenile diabetes and, because of the frequency of pregnancy toxemia, of preeclampsia in human females. They are also used to diagnose tuberculosis, because they are easily infected by human tuberculosis bacteria.

Guinea pig strains used in scientific research are primarily outbred strains. Aside from the common American or English stock, the two main outbred strains in laboratory use are the Hartley and Dunkin-Hartley; these English strains are albino, although pigmented strains are also available. Inbred strains are less common and are usually used for very specific research, such as immune system molecular biology. Of the inbred strains that have been created, the two that are still used with any frequency are "Strain 2" and "Strain 13".

Guinea pigs as food

Guinea pigs (called cuy, cuye, curí) were originally domesticated for their meat in the Andes.

To this day, cuye continues to be a major part of the diet in Peru and Bolivia, particularly in the Andes Mountains highlands. Due to the fact that they require much less room than traditional livestock and reproduce extremely quickly when compared to traditional stock animals, they can be raised as a source of food in an urban environment, unlike most livestock animals. Both rural and urban families raise guinea pigs as a source of supplementary income, and the animals are commonly bought and sold at local markets and large-scale municipal fairs. Guinea pig meat is high in protein and low in fat and cholesterol, and is described as being similar to rabbit and the dark meat of chicken. The animal may be served fried (chactado), broiled (asado), or roasted (al horno), and in urban restaurants may also be served in a casserole or a fricassee. Ecuadorians commonly consume sopa or locro de cuy, a soup dish. Pachamanca or huatia, a process similar to barbecueing, is also popular, and is usually served with corn beer (chicha) in traditional settings.

Peruvians consume an estimated 65 million guinea pigs each year, and the animal is so entrenched in the culture that one famous painting of the Last Supper in the main cathedral in Cusco, Peru shows Christ and the twelve disciples dining on guinea pig. Guinea pigs are also consumed in Ecuador, mainly in the Sierra region of the country, but are not depended upon as a staple source of protein. Andean immigrants in New York City raise and sell guinea pigs for meat, and some ethnic restaurants in major United States cities serve it as a delicacy. In the 2000s, Peruvian research universities began breeding larger-sized guinea pigs in the hope of increasing human consumption outside of South America.

References

^ Morales, Edmundo (1995). The Guinea Pig : Healing, Food, and Ritual in the Andes. University of Arizona Press. ISBN 0-8165-1558-1.
^ "Diccionario de la Lengua Española" (in Spanish). Real Academia Española. Retrieved 2007-03-12.
Gmelig-Nijboer, C. A. (1977). Conrad Gessner's "Historia Animalum": An Inventory of Renaissance Zoology. Krips Repro B.V. pp. pp. 69-70. {{cite book}}: |pages= has extra text (help); Cite has empty unknown parameter: |1= (help)
"Definition of cavy". Merriam-Webster Online. Retrieved 2007-03-12. {{cite web}}: Cite has empty unknown parameter: |1= (help)
^ Wagner, Joseph E.; Manning, Patrick J (1976). The Biology of the Guinea Pig. Academic Press. ISBN 0-12-730050-3.
^ "Results for "Guinea pig"". Dictionary.com. Retrieved 2006-08-29.
Harvey, William (1653). Anatomical exercitations concerning the generation of living creatures to which are added particular discourses of births and of conceptions, &c. pp. p. 527. {{cite book}}: |pages= has extra text (help); Cite has empty unknown parameter: |1= (help)
"Guinea Pig". Microsoft® Encarta® Online Encyclopedia 2007. Retrieved 2007-03-12. {{cite web}}: Cite has empty unknown parameter: |1= (help)
^ Richardson, V.C.G. (2000). Diseases of Domestic Guinea Pigs (2nd edition ed.). Blackwell. p. 132. ISBN 0-632-05209-0. {{cite book}}: |edition= has extra text (help); Cite has empty unknown parameter: |1= (help)
Guinness Book of World Records. Bantam. 1997. ISBN 978-0553576849. {{cite book}}: Cite has empty unknown parameter: |1= (help)
"Your Guinea Pigs' Social Life". Cavy Spirit. Retrieved 2006-10-14.
^ Terril, Lizabeth A.; Clemons, Donna J. (1998). The Laboratory Guinea Pig. CRC Press. ISBN 0-8493-2564-1. {{cite book}}: Cite has empty unknown parameter: |1= (help)
"Your Guinea Pigs' Home". Guinea Pig Cages. Retrieved 2006-08-29.
"Guinea Pigs". Canadian Federation of Humane Societies. Retrieved 2007-03-21.
Charters, Jessie Blount Allen (July 1904). "The associative processes of the guinea pig: A study of the psychical development of an animal with a nervous system well medullated at birth". Journal of comparative neurology and psychology. XIV (4). University of Chicago: 300–337. Retrieved 2006-12-27.
"Guinea Pig Sounds". Jackie's Guinea Piggies. Retrieved 2007-03-14. {{cite web}}: Cite has empty unknown parameter: |1= (help)
^ National Resource Council (1996). Laboratory Animal Management: Rodents. National Academy Press. pp. pp.72-73. ISBN 0-309-04936-9. {{cite book}}: |pages= has extra text (help); Cite has empty unknown parameter: |1= (help)
^ Harkness, John E.; Wagner, Joseph E. (1995). The Biology and Medicine of Rabbits and Rodents. Williams & Wilkins. ISBN 0-683-03919-9.
^ Percy, Dean H.; Barthold, Stephen W. (2001). Pathology of Laboratory Rodents and Rabbits (2nd edition ed.). Iowa State University Press. pp. pp.209-247. ISBN 0-8138-2551-2. {{cite book}}: |edition= has extra text (help); |pages= has extra text (help)
"Constitution". American Cavy Breeders Association. 2006-09-29. Retrieved 2007-03-22. {{cite web}}: Check date values in: |date= (help)
Buchholz, Andrea C; Schoeller, Dale A. (2004). "Is a Calorie a Calorie?". American Journal of Clinical Nutrition. 79: pp. 899S–906S. Retrieved 2007-03-12. {{cite journal}}: |pages= has extra text (help); Cite has empty unknown parameter: |1= (help)
"Guinea-pig". Oxford English Dictionary online (subscription access required). Retrieved 2007-02-22.
Kallet, Arthur; Schlink, F. J. (1933). 100,000,000 Guinea Pigs:Dangers in Everyday Foods, Drugs, and Cosmetics. Vanguard Press. ISBN 978-0405080258.
McGovern, Charles (2004), "Consumption", in Whitfield, Stephen J. (ed.), A Companion to 20th-Century America, Blackwell, pp. p.346, ISBN 0-631-21100-4 {{citation}}: |pages= has extra text (help); Cite has empty unknown parameter: |1= (help)
^ Gad, Shayne C. (2007). Animal Models in Toxicology (2nd edition ed.). Taylor & Francis. pp. pp.334-402. ISBN 0-8247-5407-7. {{cite book}}: |edition= has extra text (help); |pages= has extra text (help); Cite has empty unknown parameter: |1= (help)
Chan, Shu Jin; et al. (1984). "Guinea Pig Preproinsulin Gene: An Evolutionary Compromise?". Proceedings of the National Academy of Sciences USA. 81: 5046–5050. {{cite journal}}: Explicit use of et al. in: |first= (help)
Bowsher, Ronald; et al. (1999). "Sensitive RIA for the Specific Determination of Insulin Lispro". Clinical Chemistry. 45: pp. 104-110. Retrieved 2007-03-15. {{cite journal}}: |pages= has extra text (help); Explicit use of et al. in: |first= (help)
^ Vecchio, Rick (2004-10-19). "Peru Pushes Guinea Pigs as Food". CBS News. Retrieved 2007-03-12. {{cite news}}: Check date values in: |date= (help); Cite has empty unknown parameter: |1= (help)
Mitchell, Chip (2006-11-01). "Guinea Pig: It's What's for Dinner". Christian Science Monitor. Retrieved 2007-03-12. {{cite news}}: Check date values in: |date= (help); Cite has empty unknown parameter: |1= (help)

Misplaced Pages