Guinea Pig Click on an image to view larger version & data in a new window Cavia porcellus. Author's pet guinea pigs. Left: Shadow. Right: Chiquita. Both images © 2008 Introduction Humans have kept and used the domestic guinea pig for thousands of years. In Western societies, these social rodents are kept as pets, bred for show, and used in scientific research. In some societies, guinea pigs are a source of food, and the Andean culture uses them in religious ceremonies and traditional medicine. Classification Guinea pigs belong to the family Caviidae, which is a family of South American rodents. This group sometimes is referred to as Caviomorpha, or guinea-pig-like rodents (D'Erchia et al. 1996; Wagner 1976). Rodentia contains three sub-orders: Sciuromorpha, Myomorpha, and Hystricomorpha. Caviidae usually is placed within Hystricomorpha (Graur, Hide and Li 1991; D'Erchia et al. 1996).

However, in the early 1990s a debate arose over whether or not guinea pigs and Caviomorpha should be classified in Rodentia. Graur, Hide, and Li (1991) performed phylogenetic analyses of amino acid sequences of various taxa. Their interpretation of the results suggested that Caviomorpha should be considered a separate order from Rodentia. In 1996, D'Erchia et al. analyzed the complete guinea pig mitochondrial genome and concluded that guinea pigs should be classed in an order distinct from Rodentia. In other words, Rodentia is paraphyletic. However, Luckett and Hartenberger (1993), Sullivan and Swofford (1997), and others argued for keeping Caviomorpha in Rodentia based on morphological data and criticisms of the methods used by Graur, Hide, and Li (1991), and D'Erchia et al. (1996). Currently, some data supports the paraphyletic side of the debate, but guinea pigs are generally considered part of Rodentia.

Evolution and Domestication Ancestral caviomorphs probably descended from paramyid rodents found in North America, Eurasia, and North Africa. Members of Caviidae first appeared during the Late Miocene period, 26 to seven million years ago, and the family diversified in that period as well (Alderton 1999; Wagner 1976). The domestic guinea pig originates in the mountains and grasslands of the Altiplano region in South America. Domestication may have begun around 5,000 BCE (CFHS; Morales, 1995). Nowak (1999) asserts that Cavia porcellus probably derived from C. aparea, C. tschudii, or C. fulgida, and is now distinct from all of these. According to Alderton (1999), it was once thought that C. aparea (the Brazilian cavy) was the wild ancestor, but it is now thought that C. tschudii (the Peruvian cavy) is probably the ancestral form. Today, guinea pigs live all over the world.

They can adapt to a wide range of altitudes, from sea level to higher than 4,000 m (NRC 1991). In South America, where people keep them for food, they are allowed to run free on the floor in kitchens or outdoors (Morales 1995). Sometimes pet guinea pigs are allowed to "free range", too, but oftentimes their caregivers will keep them in cages. Guinea pigs thrive at room temperature; colder weather can be deadly (CFHS). However, guinea pigs can be surprisingly hardy. The BBC reports that a guinea pig was abandoned outdoors in Cornwall, England, and survived there for five years. Names The species name porcellus means "little pig" in Latin (Wagner 1976). Although guinea pigs are not members of the pig family, they do resemble suckling pigs when they are skinned and dressed for cooking. Also, some of their vocalizations sound somewhat like pig vocalizations (Wagner 1976; Alderton 1999). C. porcellus has several common English names, including "guinea pig", "cavy", and "cuy".

The origins of "guinea pig" are not clear. The "pig" part of their name probably shares the same origins as their species name. Europeans first encountered the animals in the mid-sixteenth century, after the Spanish Conquest of South America. It is possible that guinea pigs were sold for a guinea (a type of English coin) at that time and were thus named for their price. Or, Europeans might have thought guinea pigs came from the African country Guinea, since ships carrying the animals from South America often stopped there before returning to Europe (Alderton 1999). It is also possible that "guinea" is a corruption of the name of the South American country Guiana (Morales 1995). Another common English name is "Cavy". Breeders of guinea pigs for show often refer to them by this name, which is taken from the animal's scientific name, Cavia porcellus (Wagner 1976). Cavy may also be a modified version of the South American "cuy". This name is similar to that used by several Native South American languages.

"Cuy" sounds like a guinea pig vocalization (Morales 1995; Wagner 1976). Male guinea pigs are called boars, females are referred to as sows, and young are called pups (CFHS). Physical Characteristics Guinea pigs measure 20 to 40 cm from head to rump; they do not have tails (Nowak 1999). Like all members of Caviidae, guinea pigs have four toes on each front paw and three toes on each hind paw (Alderton, 1999). Adult guinea pigs usually weigh 500 g to 1500 g, but the National Agrarian Research Institute of Peru has developed a "super-cuy" that weighs up to 3 kg (Nowak 1999; Economist 2004)! In general, females tend to weigh slightly less than males (CFHS). Guinea pig incisors and molars grow continuously. They wear down from the guinea pig chewing its roughage-rich diet (CFHS; Navia and Hunt 1976). Senses Adult guinea pigs seem to be able to discern brightness, but not hue.

Young are born with their eyes open, but studies reported by Harper (1976) suggest that their vision is poorly developed at birth. Scent plays a role in guinea pig communication, and mother guinea pigs use it to identify their young. Guinea pigs can hear sounds of up to 40,000 to 50,000 Hz, and some guinea pig vocalizations have ultrasonic components above 20,000 Hz (Harper 1976). Coat The wild relatives of guinea pigs have ticked grey coats similar to that of Shadow (see pictures). Breeding guinea pigs for research and show has produced many combinations of coat colour, length, and quality. Sewall Wright studied guinea pig coat type and pigmentation extensively (Festing 1976; see Wright 1935 for an example of his research). Common colours include white, brown, black and combinations thereof. Guinea pig fur may be long or short, straight, frizzy or curly, soft and silky or rough and harsh, and it may lie smoothly or in rosettes (Morales 1995; ACBA).

Behaviour Activity Guinea pigs are most active at dawn and dusk, but they are active throughout the day. Under conditions of constant light and temperature in the lab, they do not appear to have fixed sleeping or eating patterns (Harper 1976). Social Behaviour As social animals, guinea pigs will seek contact with one another and tend to associate in groups of several to several dozen if given the opportunity to do so. They investigate unfamiliar guinea pigs by nose-to-nose contact and anogenital nuzzling (Alderton 1999; Harper 1976). Guinea pigs interact and socialize with their caregivers when kept as pets (CFHS). For example, they may chirp at their caregiver to ask for food. In groups of guinea pigs, males have a linear hierarchy. The alpha male has exclusive rights to mating with the females in his group, and will not tolerate other males attempting to mate with his females. Females are subordinate to their male, and they may have a loose social hierarchy among themselves (Harper 1976). Locomotion Guinea pigs are quadrupedal. They walk and run on the soles of their feet (Alderton 1999).

Young guinea pigs play by "popcorning", that is, by jumping, bucking, and throwing up their heads (CFHS; Harper 1976). In response to danger or fright, guinea pigs will either freeze or run away. Groups of guinea pigs may respond by suddenly scattering in all directions (Harper 1976). Communication Guinea pigs communicate with one another by making sounds (CFHS; NRC 1991). They produce a variety of vocalizations that go along with certain activities. For example, a guinea pig will "chutt" when exploring, "whistle" when fed by a caregiver or when separated from a companion, and "purr" when seeking contact (Harper 1976). Guinea pigs also use scent to communicate. Scent from adanal glands may be used to mark territory. In courtship, an unreceptive female will sometimes squirt a jet of urine at the persistent male, who then sniffs it. While the male investigates, the female escapes. Alternatively, the persistent male may squirt urine at the female, possibly in an attempt to mark her as part of his group (Harper 1976).

Feeding Guinea pigs are herbivores (CFHS). They feed in groups with little competition for food (Harper 1976). Unlike other rodents, guinea pigs cannot manufacture vitamin C; they must consume it in their diet. Sources of dietary vitamin C include fresh vegetable matter and supplements that caregivers add to food or water (CFHS; Ediger 1976; Navia and Hunt 1976). To extract as much nutrition as possible from their cellulose-rich diet, guinea pigs use coprophagy. They cannot digest cellulose themselves, but bacteria in their cecum can. However, once food has reached the cecum, guinea pigs cannot absorb nutrients from it. So, they pass and eat special, soft fecal pellets containing bacteria-digested cellulose (Alderton 1999; Harper 1976). Click on an image to view larger version & data in a new window Cavia porcellus. Shadow feeding on a lettuce leaf. © 2008 Reproduction and Life Cycle Reproductive Cycle and Mating Sexually mature female guinea pigs go into estrus every 13 to 20 days except when pregnant.

The vagina is closed by a membrane, which disappears at the beginning of estrus and re-forms at the end (Ediger 1976). A male guinea pig courts a female by purring, swaying his hindquarters, following or circling, and licking and sniffing the female's anogenital region. The female also purrs, sways, circles and licks the male. To indicate receptivity, the female raises her hindquarters. After mating, the male guinea pig grooms his genital region and drags his hindquarters along the ground. In the female, a plug made of sperm and vaginal cells forms in the vagina, and falls out a few hours later (Harper 1976). Pregnancy and Birth Pregnancy lasts about 68 days. Guinea pigs give birth to, on average, two to three young per litter. Newborn pups each weigh about 85 g to 95 g at birth. After the pups are born, the mother eats the placenta and fetal membranes (Harper 1976). In order to give birth, the mother's pubic bones must separate, as the pups are large.

If a female guinea pig does not breed before six months of age, her pubic bones may fuse. If this happens, it prevents her from giving birth, resulting in the death of the mother and her unborn pups (NRC 1991; Harper 1976). Precocial Young Guinea pig pups are precocial. They are born fully-furred, with well-developed sensory and locomotor abilities, and they can consume solid food the same day they are born (Kunkele and Trillmich 1997). Pups can be weaned after five days, but they normally nurse for three weeks or more. Milk consumption decreases as solid food consumption increases (Nowak 1999; Kunkele and Trillmich 1997; Harper 1976). The mother grooms her young very little. She does lick the anogenital region of her pups for the first two or three weeks in order to stimulate urination (Harper 1976).

Kunkele and Trillmich (1997) found that having precocial young does not significantly lower the overall biological cost of lactation for the mother, since the well-developed young have high energy needs right after birth. However, the pup's milk consumption decreases rapidly, and so daily maternal energy expenditure decreases also. This strategy may enable guinea pigs to breed throughout the year, even in times of scarce food. Maturity and Life Span Females reach sexual maturity at two months of age; males reach it at three months (Nowak 1999). Pet guinea pigs usually live five to seven years if given proper care (CFHS). Uses South American Culture Guinea pigs have been an important part of South American culture in the Andean region (in Colombia, Ecuador, Peru, and Bolivia) for thousands of years. Incans used them in religious ceremonies, and they also mummified them (Alderton 1999; Morales 1995). The Spanish Conquest introduced Roman Catholicism to South America, and traditional beliefs and practices combined with the new religion. For example, people in Peru use guinea pigs in the celebration of patron saint days.

Also, Andean traditional medicine uses guinea pigs for diagnosis and healing (Morales 1995). Meat In South America, guinea pigs are eaten on special occasions and are considered a delicacy. Today, there are commercial guinea pig farms in South America, but many Andeans still raise them in the traditional manner. The animals run loose in kitchens where they feed on kitchen vegetable scraps (Morales 1995). Guinea pigs are also a source of meat in Nigeria and other parts of Africa, as well as in the Philippines (NRC 1991). Pets Guinea pigs are kept as family pets and bred for showing. Cavy breeding clubs in Europe and North America, such as the American Cavy Breeders Association, set breed standards and organize shows and competitions. Scientific Research Guinea pigs have been used in scientific research since the mid-1800s for studying pathology, nutrition, heredity, and toxicology, and for the development of serums (Nowak 1999; NRC 1991). Various aspects of their physiology and anatomy make them ideal lab animals.

For example: Guinea pig gestation is long enough to permit easy differentiation between stages of embryological and fetal development (Hoar 1976). Guinea pigs are useful for studying collagen biosynthesis, as they do not produce their own vitamin C, unlike other small lab animals such as mice, rats, and hamsters (Navia and Hunt 1976). Collagen biosynthesis requires vitamin C. Compared to that of other small lab animals, the guinea pig electrocardiogram waveform is more similar to the human waveform. Also, guinea pigs generally are calm animals, so it is possible to obtain continuous and stable readouts (Sisk 1976). Hearing studies use guinea pigs since their inner ear is readily accesible (McCormick and Nuttal 1976). Guinea pigs are ideal canditates for germ-free research, since their precocial young have a good chance at surviving from birth on solid food. Scientists surgically remove the pups from the pregnant guinea pig in a sterile environment, and then raise them on sterile food in a germ-free environment (Wagner and Foster 1976).

Information on the Internet The Canadian Federation of Humane Societies (CFHS.) Information on keeping guinea pigs as pets. References ACBA. American Cavy Breeders Association. Alderton, D. 1999. Rodents of the World. New York: Sterling Publishing Co., Inc. CFHS. The Canadian Federation of Humane Societies. D'Erchia, A.M., C. Gissi, G. Pesole, C. Saccone, and U. Arnason. 1996. The guinea pig is not a rodent. Nature 381:597-600. Economist. 2004. A guinea pig for all tastes and seasons. 17 July. Accessed using Business Source Complete. Ediger, R.D. 1976. Care and Management. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 5-12. New York: Academic Press, Inc. Festing, M.F.W. 1976. Genetics. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J.

Manning, 99-120. New York: Academic Press, Inc. Graur, D., W.A. Hide, and W.-H. Li. 1991. Is the guinea-pig a rodent? Nature 351:649-52. Harper, L.V. 1976. Behaviour. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 31-51. New York: Academic Press, Inc. Hoar, R.M. 1976. Toxicology and Teratology. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 269-280. New York: Academic Press, Inc. Kunkele, J., and F. Trillmich. 1997. Are Precocial Young Cheaper? Lactation Energetics in the Guinea Pig. Physiological Zoology 70:589-96. Luckett, W.P., and J.-L. Hartenberger. 1993.

Monophyly or Polyphyly of the Order Rodentia: Possible Conflict Between Morphological and Molecular Interpretations. Journal of Mammalian Evolution 1:127-47. McCormick, J.G., and A.L. Nuttal. 1976. Auditory Research. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 281-304. New York: Academic Press, Inc. Morales, E. 1995. The Guinea Pig: Healing, Food, and Ritual in the Andes. Tuscon: The University of Arizona Press. Navia, J.M., and C.E. Hunt. 1976. Nutrition, Nutritional Diseases, and Nutrition Research Applications. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 235-268. New York: Academic Press, Inc. Nowak, R.M. 1999. Cavies, or Guinea Pigs. In Walker's Mammals of the World, 1667-9. 6th ed. Vol. 2.

Baltimore: The Johns Hopkins University Press. NRC. National Research Council. 1991. Microlivestock: Little-Known Small Animals With a Promising Economic Future. National Academy Press. Sisk, D.B. 1976. Physiology. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 63-98. New York: Academic Press, Inc. Sullivan, J., and D.L. Swofford. 1997. Are Guinea Pigs Rodents? The Importance of Adequate Models in Molecular Phylogenetics. Journal of Mammalian Evolution 2:77-86. Wagner, J.E. 1976. Introduction and Taxonomy. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 1-4. New York: Academic Press, Inc. Wagner, J.E., and H.L. Foster. 1976. Germfree and Specific Pathogen-Free. In The Biology of the Guinea Pig, eds. J.E. Wagner and P.J. Manning, 21-30.

New York: Academic Press, Inc. Wright, S. 1935. On the genetics of rosette pattern in guinea pigs. Genetica 17:547-60. Learning Information What to Consider When Making the Decision to Neuter Your Guinea Pigs - Guinea Pig Today Guinea Pig Today Image courtesy of Orange County Cavy Haven Wash and Carter are bonded male pairs available for adoption through Orange County Cavy Haven. “Should I neuter my guinea pig?” This is a question that many new guinea pig owners ask. They may have a lonely male guinea pig, or two adolescent boars that are not getting along. Or, they may have found themselves with a male and a female, usually due to miss-sexing at the pet store. Often, people turn to rescuers or veterinarians to find out the answer to their questions. The topic comes up frequently in online communities such as Guinea Lynx . Answers vary, depending upon who is responding. As with any surgery, the owner should ask themselves these three questions before proceeding: 1) is it necessary? 2) is a beneficial? 3) is it safe?

Some animals, like cats, dogs, and rabbits, are neutered to control the pet overpopulation problem. In the United States, shelters kill 3 to 4 million cats and dogs every year. Guinea pigs are often found in public shelters as well, enough to keep over 40 official guinea pig rescues operating at full capacity most of the time. Often, these rescues are burdened with dozens of guinea pigs at once from backyard breeders or accidental breeders such as in the 2011 Baldwin Park shelter dump , which filled up four California guinea pig rescues and one in Arizona with 152 undernourished, feral guinea pigs, many of whom were pregnant. For this reason, many rescues advocate neutering and spaying all guinea pigs. In addition to population control, some animals are neutered to prevent potential health issues. Although male guinea pigs do sometimes develop mammary cancer, there is no evidence to support the idea that neutering male guinea pigs will prevent this from occurring. Reproductive cancer in male guinea pigs is rare. Neutering males has no proven health benefits, although it may have an effect on hygiene.

Owners of intact male guinea pigs will need to check the perineal sac occasionally, and clean out any debris with Q-tips and mineral oil. Neutering a guinea pig makes the sac less likely to collect debris. In addition to the health and overpopulation concerns, other pets are frequently neutered to control behavioral problems that result from an excess of hormones. However, the consensus among guinea pig experts is that neutering does not affect territorial herd behavior among males. Some owners have observed that their guinea pigs were calmer with people after being neutered. Yet it is rare that neutering affects guinea pig social dynamics. As animals with distinct social hierarchies, they may exhibit aggressive behavior when forced to share amenities, especially if more than one dominant guinea pig is in the group. Neutering is unlikely to affect this behavior. Given enough space, amenities, and an appropriate companion, the majority of male guinea pigs can live out their lives happily in a cage with another male. Rescuers generally pair either two adult males or an adult male with a baby, to avoid having two adolescents together. Adolescents exhibit more hormonal behavior than adults and therefore two in the same cage is not a good idea.

Personality is key; some guinea pigs are dominant and must be placed with a submissive companion. This is true of females as well. Image courtesy of Orange County Cavy Haven Theo and Van Gogh are bonded male pairs available for adoption through Orange County Cavy Haven. What about when an owner accidentally finds themselves with guinea pigs of the opposite sex? The options are to let the guinea pigs live alone or get them each a same sex companion. In this case, neutering is not necessary but it would benefit both the guinea pigs and the owner. However, is it safe? This largely depends upon two factors: 1) Finding an experienced veterinarian; and 2) Providing appropriate, knowledgeable, proactive post-operative care. How do you find a good exotics veterinarian? Seek recommendations from rescues or online communities such as Guinea Lynx, which has a recommended vet list . Choose the veterinarian who has neutered the most guinea pigs successfully, and will provide you with two crucial post-operative tools: antibiotics and pain medicine. Armed with a good veterinarian, antibiotics, and pain medicine, an informed guinea pig owner can provide adequate post-operative care.

However, both guinea pigs’ fragility and their lack of hygiene may predispose them to post-surgical complications. Read the Guinea Lynx post-op care guide before taking your guinea pig in for any surgery. Most guinea pig neuters, if done by a skilled veterinarian, will turn out fine. However, in rare cases, severe complications such as hernia, infection, adhesions, and bloat may occur. Guinea pig owners should be extremely vigilant when caring for a guinea pig that has just been neutered. They should find out where the incisions will be so that they can watch this area for signs of infection. Some veterinarians perform a scrotal neuter, so there will be two incisions on the scrotal sac. Other veterinarians prefer a pre-scrotal neuter, which is done with a single incision above the scrotal sac. More detailed information on neutering techniques can be found on Cavy Spirit’s neutering page . A few rescuers neuter all their male guinea pigs with very few incidents. They are using much practiced veterinarians and the best post-operative care.

Some veterinarians will recommend spaying all female guinea pigs for health reasons, but few advocate neutering all males. For the average guinea pig owner, neutering is usually done as a convenience for the owner, and should be undertaken only after plenty of research and commitment to intensive post-operative care should it become necessary. We would like to give special thanks to William Ridgeway, D.V.M. of Long Beach Animal Hospital and Irene Mary Cóté DVM of Côté Animal Hospital for their advice. If you have a great idea for an article about guinea pigs, please let us know. Guinea Pig Today is a network of guinea pig lovers and we’re always looking for the next great story. View our submissions page for more information on how to submit your idea. Related Posts Guinea Lynx :: Guinea Pig Care Guide See also: How to Recognize Quality Pellets Grass Hay: Unlimited high quality, grass hay (timothy and orchard grass are popular) should always be available to each and every guinea pig, no matter what age. Grass hay keeps their digestive system moving and helps prevent their teeth from over growing. It is usually placed in a wire rack off the floor for cleanliness.

Alfalfa hay can be given to young guinea pigs, pregnant, nursing or malnourished adults. But because of its high calcium content, alfalfa should be reserved as a treat for the average adult guinea pig. Excess calcium could contribute to the formation of bladder stones in older guinea pigs. Remember that alfalfa is NOT a replacement for grass hay, but can be used to supplement the diet of some pigs. Grass hay should always be available to all guinea pigs. See also: Grass Hay -- Selecting Hay Vegetables: Small amounts of fresh vegetables (about a cup a day) are an important additional source of vitamin C and other nutrients. Parsley, romaine lettuce (rather than iceberg, which has less nutritional value and may result in loose stools if given in excess), a small piece of carrot, tomato, green or red pepper, spinach, and cantaloupe are popular choices. And clean, pesticide-free grass, clover, dandelion greens, corn husks and silk, will be appreciated by your pet. Rinse vegetables thoroughly. Do not feed wilted or spoiled food. Vegetables must be introduced slowly, to avoid digestive upsets.

Once introduced, you can supply a variety of them to your pet. Variety is the key to maintaining your pigs' health. Be creative. See also: "My Favorite Vegetables and Fruits" See also: Vegetable/Fruit Chart for vitamin C, calcium and oxalic acid content of many foods. Optional: Unsweetened, pure cranberry juice, changed daily, is an excellent source of C and helps prevent some urinary tract infections. Make sure that grass hay, water, and pellets (see note below) are always available (most guinea pigs will not over eat). Vegetables can be provided two or more times a day, removing uneaten vegetables to prevent spoiling. Note: Guinea pigs prone to forming stones are sometimes fed limited or no pellets. Since pellets are a concentrated food source, be sure to review guidelines for determining if your guinea pig is a good weight. Some pet owners restrict pellet intake to 1/8 cup a day for adult guinea pigs.

See: Determining The Correct Weight For Your Guinea Pig contributed by Sandra Mitchell, DVM, DABVP (Exotic Companion Mammal and Feline Specialties) NOT RECOMMENDED IN DIET: Mixes or treats with nuts, seeds, dried fruit and dyed pieces. Do not give dairy and meat products (guinea pigs are herbivores) or rabbit pellets (they do not contain Vitamin C and some may even include antibiotics toxic to guinea pigs). Seeds in husks can be a choking hazard. Cruciferous vegetables (cabbage, collards, bok choy, broccoli) may cause gas in your pet and are best offered sparingly and infrequently. Do not use mineral wheels. Never use Tang (which contains dyes, refined sugars, and very little vitamin C) in drinking water. And don't fall for commercial treats marketed for guinea pigs (like yoghurt drops) which can even be detrimental to their health. Consuming these empty calories (many contain fat, sugars and even excess calcium) can result in decreased consumption of the basic foods they really need. Do not give multivitamins! Plain vitamin C is fine, but multivitamins are not.

Excesses of fat soluble vitamins like A and D can cause serious problems for your pet. Exercise Just as exercise is essential for us, so is it important for our pets. Daily exercise will help your guinea pig maintain good health. Find an enclosed space with an easily cleaned floor such as a bathroom or kitchen and they will slowly begin to look forward to the freedom a larger space will give them. They will especially enjoy this time if you hide favorite foods in the area. A few hiding places provide a place to feel protected while they are getting used to the new space. Brown paper bags with the lip folded over for stability, soda can and tissue boxes with holes cut in the sides work well. You can also include a few pieces of PVC pipe fittings for him/her to race through, as well as a brick or rock as obstacles to run over (useful for wearing down their nails). Some guinea pigs enjoy chewing on cardboard tubes (slit lengthwise for safety) from toilet paper or paper towel rolls. Toilet paper rolls stuffed with hay make especially fun toys for cage or floor time. A large cage which is laid out to encourage movement from one area to another through placement of food, water, and shelter can also help keep your guinea pig healthy.

Introducing a second level or moderate barrier that must be climbed over will help develop and maintain agility. Not Recommended: Exercise wheels or balls are not good for guinea pigs and may injure their spines, legs or feet. Grooming Brushing: Daily brushing with a soft baby brush or a metal greyhound comb will help remove some of the loose hair and lessen shedding. Daily brushing is especially important for long haired guinea pigs, less necessary for the short haired varieties. Bathing: Guinea pigs seldom "need" baths and some are never bathed. But if they do require one, a shampoo formulated especially for small animals will help avoid drying their skin. Use a shallow bowl of warm water, rinse, and dry thoroughly to avoid chills before returning them to their home. Avoid getting water in their ears. Shampoos: Bunny Bath by Four Paws is a pleasant smelling all purpose shampoo which can be used on guinea pigs. Hylyt Hypoallergenic Shampoo is a soap free product excellent for use on sensitive skin. EPI-SOOTHEï¿½ SHAMPOO is a gentle shampoo formulated to relieve mild itchiness and dry skin in dogs and cats also used by some people on their guinea pigs.

Note: if your pet is extremely itchy, is shedding more than normal, or has a lot of dandruff, a parasite or fungal infection are the most likely causes. None of the shampoos mentioned here are designed to treat these problems though Hylyt and Epi-Soothe may temporarily relieve some of the pain. Read mange mites and fungus to find out how important it is to promptly treat these conditions. Clipping Toenails: Monthly clippings, begun early, will help accustom the animal to this necessary activity. A scissors style small animal clipper provides good control. Paying close attention to the location of the "quick" will help avoid cutting into the living part of the nail. A light shown from beneath dark colored nails may be helpful locating the quick if it is hard to see. If the nail is accidentally cut too short, a styptic pencil will help stop bleeding. For more tips on clipping nails check out Clipping Toenails . Taming Your Pet Guinea pigs make good pets for children over the age of six. Most become tame and loving pets who enjoy being cuddled. On first arriving home, your pet will appreciate being left alone for a day to adjust to the new environment.

Although new guinea pigs may not like to be picked up at first and will race around the cage to avoid it, a little bribery with some enticing veggies and some patience will help get them used to your company. They are easily startled so use a quiet voice and slow movements to help keep them calm and a towel while holding them to avoid accidents. When lifting and carrying your guinea pig, be sure to support the entire body with two hands. Guinea pigs are easily injured if dropped, and may nip or bite if not properly handled. Small children should be supervised when holding a guinea pig and should NOT be allowed to pick one up from out of the cage or carry it around. Breeding Female guinea pigs can be sexually mature as early as 4 weeks old. Gestation is from 59 to 73 days and average litter size is 1-4. Breeding guinea pigs is not recommended. Not only is it risky, it is difficult to find homes for the young with responsible and caring people -- your candidates may "disappear" when the time comes to adopt out the babies. Guinea pig sows are at risk of pregnancy complications because the babies are born large and ready to run.

Breeding after 8 months of age can be fatal for a guinea pig who has not had a previous litter due to dystocia. The symphysis (a joint of tough fibrous cartilage which firmly joins the 2 pubic bones) can stiffen upon reaching adulthood and she may not be able to deliver her pups unaided. Sows with dystocia usually need a caesarian section. The survival rate is very poor. Spaying or neutering guinea pigs also carries risks even when performed by an experienced guinea pig veterinarian. The safest choice is to keep the sexes separate or have only sows or boars. Should you find yourself with a pregnant guinea pig, read over the advice and links on the breeding page. Since most sows will have an estrus (a time when they can become pregnant) from 2 to 15 hours immediately after giving birth, remove any boar from the cage as the delivery date approaches to prevent back-to-back pregnancies. Sexing Guinea Pigs Make absolultely sure your pet has been correctly sexed. If you have more than one and plan on housing them together, ensuring that both pigs are the same sex will avoid the many pitfalls and risks associated with pregnancy.

Petstores are notorious for sending home two "same sex" guinea pigs that are anything but, so check yourself or have a vet check your pigs for you. Should you determine you have a male and female, separate them immediately whether you suspect the female is pregnant or not. Boars (male guinea pigs) are generally larger than females, have smaller nipples, and when sexually mature, clearly visible scrotal pouches. Gently pressing on the belly near the genitals will allow the penis to emerge. A sow (female guinea pig) has a Y shaped opening which is usually sealed with a vaginal closure membrane, according to Harkness and Wagner. In younger pigs, determining sex may be difficult. Waiting until two or three weeks of age may allow the pig to mature enough to make a determination easier. Small young male pigs have a donut shape to their rectum, totally round or slightly oval, and at the top of this donut, a little dot (sometimes described as an "i"). Place your index finger and thumb on either side of the genitals and gently spreading the area -- not much happens with a boy, but with a sow a definite Y appears and the base of the Y (under the "V") will spread quite a bit.

Some females will have what has been described as a "pimple" (which might be confused with the dot described above). According to ThePetLady, "...if you put your finger directly above the pouch and push inward and slightly downward, gently but firmly, and absolutely nothing pops out (not even a little bit) then it has to be a girl," but warns this is very difficult to do with very young guinea pigs as their genitals are small. ThePetLady also suggests going to a pet store to examine a few pigs, since it is much easier to see the differences when you have both sexes to compare. One of Pinta's hints is that sows pee outward and boars pee inward. LINKS! Still confused? Be sure to check the Cavy Spirit sexing page, which should answer any questions you have. Teresa Murphy provides numerous pictures of young, mature, and neutered guinea pigs. Veterinary Care While guinea pigs can live a long healthy life, it is always wise to provide regular veterinary care. Vets qualified to care for your guinea pig are called "exotics veterinarians".

Experienced guinea pig owners can't stress enough how important it is to find a good vet who knows your animal before you are in the middle of an emergency. Check advice on How to Find a Veterinarian if you are unsure how to choose a competent vet. A wellness check will familiarize the vet with your guinea pig and give you a chance to ask questions. The vet can check for parasites, show you how to trim the nails, make sure the teeth are in good shape, and the guinea pig is in good health. Weigh Your Guinea Pig Weekly! The easiest way to monitor your pig's health is to weigh it once a week. A kitchen scale works great. Keep a chart! Often the first sign of illness is weight loss. A chart will enable you to spot gradual weight loss and get medical help early, when many illnesses are most effectively treated. You can download a record page from this site if you'd like to keep all the weigh information in one place. And consider ordering a Cavy Health Record Book with health and care advice; weight and treatment sheets; and more.

Signs Which Warrant A Trip To The Vet ASAP: If your guinea pig shows any of these symptoms, it should see a vet immediately: Refusal to eat or drink, labored breathing, wheezing, crusty eyes, sneezing , rough or puffed up coat, dull and/or receding eyes, lethargy, hunched posture, diarrhea, blood in urine, limping, excessive scratching, hair loss, or loss of balance. Be an observant owner. Unusual behavior (like sitting with it's face in a corner, and being slow to respond to you) could also be reason for alarm. When a guinea pig is ill, it can go downhill very quickly. Prompt, competent veterinary care is crucial to saving the life of a sick guinea pig. The Emergency Medical Guide will provide you with more detailed information. WARNING: Any penicillin-based drugs (like amoxicillin) are toxic to pigs. Make sure your pig is not prescribed these drugs. If you are not sure - ask. Check the DANGEROUS MEDICATIONS list for other drugs to avoid. Baytril (an excellent broad spectrum antibiotic) should not be given to baby pigs since it can interfere with growth.

Don't be afraid to call your vet if you have any questions. Most illnesses, when caught early, can be cured fairly easily with a course of antibiotics safe for guinea pigs. Guinea pigs can hide symptoms in the early stages of an illness, so once the symptoms become apparent, they may have been ill for one or two weeks. Please enjoy your new guinea pig. (S)he will prove to be a fascinating and wonderful pet. We are happy to share our lives with ours and wouldn't have it any other way! Forums More information on medical issues and links to other useful sites can be found right here at Guinea Lynx . And fellow guinea pig owners can also offer you advice on these forums: Guinea Pig Neutering, How to Neuter your Guinea Pigs Cat & Dog vs. Exotic Vets Please do not assume that any vet can do a guinea pig neuter. Most cat and dog vets should NOT do a guinea pig neuter. You need to find a vet who has done quite a few guinea pig neuters AND has a high success rate doing them. Guinea pigs are usually seen by what is referred to as an "exotic" or small animal vet.

Exotic vets usually focus on rabbits, rodents (guinea pigs), birds, reptiles, and other small creatures. Vets who spend their time on cats and dogs do not have a lot of experience with the many other species of small animals. It can be difficult to find a vet with good guinea pig experience. The testicles of dogs and cats are relatively prominent and outside of their body. The inguinal (groin) rings of guinea pigs are open and testicles can be retracted into the abdomen. If not done properly, the abdominal contents can prolapse through the suture sites, causing death. Guinea pigs should not be medically treated like little dogs and cats. Low Cost Spay/Neuter Clinics Many shelters have spay/neuter clinics. They routinely perform neuters on cats and dogs, and usually at low prices. When you are looking at comparing the cost of a neuter for your guinea pig, please be very careful about choosing a shelter to do this for you. Most shelters have a variety of vets on staff. Also, some shelter clinics cannot afford the latest and greatest equipment needed.

Be vigilant on qualifying the VET at the clinic on their personal neuter experience and success as well as practices at the clinic. The lowest cost option may not be the best one. Be very careful. Costs How much does it cost? It can cost anywhere from $35 to $300--even within the same town. There is no one answer; what a vet charges varies greatly. Almost every vet will insist that you bring the guinea pig in for a first-time health check visit, and rightly so. The cost of a neuter varies greatly. And of course, the cost of vet care is going to vary by geography. As a non-scientific sampling, here are all the office visit and neuter fees (Fall 2001) for the vets in the Greater San Francisco Bay Area which are on our vets page: 1st time What to Ask a Vet Finding a good vet Call the rescue nearest you (even if it's a good distance) and ask for a recommendation. Many rescues routinely have their cavies neutered prior to adoption and know of good vets in their area and may know of vets in the larger region or state.

Please note that breeders are NOT necessarily a good source for a vet reference. Most breeders do NOT neuter their guinea pigs! Vets who work with breeders and 4-H clubs often tend to approach guinea pigs as stock animals rather than as beloved companions. They may never have done a spay or neuter and 'treatment' of any difficulty may result in a decision for euthanasia. When dealing with stock or show animals, the financial bottom line may be the primary consideration. Breeders, by definition, accept a certain percentage of deaths as part of the process. If they didn't, they wouldn't breed. 1 2 Go through the vet section in your yellow pages. Call some of the non-exotic vets and ask them who they think the top 3 guinea pig vets are in the area. Make a list. Go through your questions with the list leaders. In the yellow pages, look for specialties in 'small animals' and/or 'exotics.' If you live in a rural area and don't have many choices, please consider expanding how far you will drive. You will only get your guinea pig neutered once. Finding a good vet can be a life or death decision for your pet.

Keep in mind that a vet who advertises as a small animal or exotic vet isn't necessarily an expert or even competent with guinea pigs. Some exotic vets have a particular animal that they favor and have good experience with. A guinea pig may or may not be one of them. It's just a starting point for you to do further qualification. Experience and success rate How many guinea pigs have you neutered? The higher the number the better of course. Under 10 is not very many. 30, 50, 100+ are the kinds of numbers to look for. You might also consider rabbit neuters in your assessment as they are somewhat similar in protocols and treatment. Over what period of time? Has the vet neutered 30 guinea pigs over a 30-year career? Or has the vet neutered 30 guinea pigs in the last 2 years? Numbers and statistics can be misleading. How many have you neutered in the last 6 months? Zero? One or two? Three or four? Ten plus? The more the better. What is your success rate?

If the vet quotes you a number, ask them if that is those that have survived surgery or if they also know for certain if they have lived through full recovery. A vet's success rate should be 98% or better. Ask for several patient references. They may have to get back to you on that, but they should have no problem providing you references of some of their successful neuters. What kind of complications have you experienced? If you are well-read on this subject, then the answer might give you some insight. This question gives the vet an opportunity to talk to you about some of the known issues and not just provide a simple black and white answer. If he or she says they have not experienced any complications, ask them what complications are possible. This question may also lead them to telling you about proper post-surgical care. Surgical technique used What anesthesia does the vet use? Isoflurane gas is preferred. Halothane and methoxyflurane gas are NOT considered safe. Injectable methods are NOT recommended either. A new "isoflurane" called "sevoflurane" is being marketed.

It takes them up and down faster than isoflurane, making it more safe or dangerous, depending on the anesthesiologist. Assistants What are the qualifications of the personnel who assist during surgery? You want to make sure that the person or people assisting during surgery are properly educated and qualified. A "veterinary assistant" could be anyone with no guarantee of any formal education or training at all. The following signify that a technician has earned a degree from an accredited veterinary technician school. Licensure of vet techs varies from state to state. Healthy! Your guinea pig should have already been seen by the vet prior to his castration appointment. Some vets will do a blood test to check for hidden health problems. If you suspect any health problems, wait until your guinea pig is completely healthy. See your vet to resolve any health issues. Proper weight and age. The age at which a vet is willing to castrate a cavy varies. Some have a two month minimum, others 3 or 4. Four months old is preferable. He should also be a good weight. 650 grams is the minimum, heavier is better.

We have had guinea pigs neutered who are 3 to 4 years old as well. While there isn't an age limit on a healthy adult guinea pig, seniors should not be subjected to the additional stress of undergoing unnecessary surgery. Fasting prior to surgery is NOT necessary. At most, removing food one or two hours prior to surgery is all that is necessary. Food should be available for the post-surgery recovery period. Fasting animals too long can cause hypoglycemia and gastrointestinal changes resulting in an inability to properly use the nutrition they get post-operatively. Cavies do not vomit and that is another reason fasting is not necessary. Vomiting post-operatively is a main reason we fast cats, dogs, and even humans. It is a cause of aspiration pneumonia and/or choking, but not an issue with guinea pigs. Castration Protocols Here are two examples of surgical protocols for castration, written by a vets who have significant castration experience with a very high success rate. Please feel free to print these protocols out and share them with your vet, PRIOR to your guinea pig's castration appointment. Your vet should be willing to read them and discuss them with you.

If you would like to be put in contact with some vets who use these or similar protocols for neutering, please email us and we will provide you with contact information. Please allow at least a week's lead time. The boar should have a complete physical exam by a veterinarian to minimize the risks of anesthesia. Guinea pigs cannot vomit, so it is not recommended to fast them before surgery. Fasting can also disrupt normal gastrointestinal motility resulting in digestive problems. Each hospital and veterinarian have their own protocol. A complete physical exam is given. EXAMPLE ONE Before placing the boar in the chamber, a lubricant is instilled into both eyes. The isoflurane seems to irritate a guinea pig's eyes and cause excessive tearing. The boar is placed in a chamber and induced with isoflurane gas. Once the boar is asleep, his mouth is swabbed with cotton swabs to remove food particles. Guinea pigs tend to have a lot of food particles in their mouth after eating, which they can aspirate under anesthesia. He is maintained under isoflurane on a mask.

During the procedure, his heart rates and oxygenation are measured with a pulse oximeter and he is monitored by the assisting technician. The boar is placed on his back with his neck supported. He is placed between two warm bags to maintain his body temperature. The scrotal area is clipped and surgically scrubbed. The area is then sprayed with Betadine. Special care is taken to clean out the rectal area to prevent contamination. The area is then draped. A small incision is made through the scrotum and tunic. The testicle is then extruded. The vas deferens and plexus are ligated and then transected. After they are pushed back in, the inquinal ring is then sutured, especially if the fat pads are minimal. The tunic is closed with a single ligature using PDS. Chromic gut is not recommended because it causes a lot of tissue reaction and can predispose the guinea pig to infection. The same procedure is performed on the opposite side. The skin incisions are then closed with skin glue. Post operatively, the boar is monitored carefully and kept warm.

He is given a dose of a nonsteroidal anti-inflammatory (Ketoprofen) and pain medication (Butorphanol). The Butorphanol often times prolongs his recovery but he seems to be in less pain. If any contamination or complication is suspected, he is sent home on a short course of antibiotics. He should be active and eating usually within 2 hours after surgery. He is sent home the same day and it is recommended that his owner keep him quiet and comfortable. The owner should make sure that he remains active and continues to eat normally. It is also best to keep him isolated until he has completely recovered. EXAMPLE TWO Waiting period Make sure you wait three to four weeks after surgery before placing your neutered male with a female. The male needs time for any live sperm to die or work its way out of his system. Residual benefits of neutering males The only reason to neuter your boar is to render him sterile so that he can be with females without risk of pregnancy. However, there are some potential side benefits with neutered male guinea pigs. As male guinea pigs age, some boars will develop an impaction problem when they get older.

Neutering tends to decrease the chance of impaction later in life. It seems that the sometimes large testicles can contribute to the impaction of the rectal pouch area. Some males have an active scent gland (just about the tail area) with a noticeable waxy or greasy buildup. Neutering seems to reduce the waxy scent gland buildup. While sexual and aggressive behavior does not change much with a male once neutered, for some guinea pigs, over a longer period of time, their sexual aggression is reduced. Additional Information 1 Case in point about finding a vet: (April/May 2002, SF Bay Area, California) We received a phone call from a woman looking to find homes for 7 babies just born. The story: They had an adult pet male guinea pig. The husband works for the municipal park system. A couple of months ago, he found a guinea pig abandoned in a container next to a dumpster. It had been raining all day. The pig and the bedding were soaked. He took it home. They called a vet; based on what they were told, they determined it was a male. Put it with their male. "He" was a pregnant she -- a beautiful American black.

She delivered two babies, which they have since found homes for. After another phone call, they realized they were supposed to take the male out right away. It was 12 hours after delivery. Too late. The female gets pregnant again. They want to do the right thing. They take their original pet male pig to a vet (who does see guinea pigs) to be neutered while the female was pregnant. The day after the surgery, the male guinea pig herniates. She described it as his guts coming out. This generally happens when the inguinal ring is not properly sutured. Their pet male pig died. They had received no special care instructions and no medication. I called the vet's office. According to the receptionist, in his 30-year career, he has seen lots of guinea pigs. She was unable to provide me with any numbers. I asked for a reference. The reference I was given was a breeder (as someone who she recalled who brings in their guinea pigs). Interestingly enough, this breeder, who lives in the same town as the couple, specializes in American blacks. 2 Breeders and Acceptable Losses Please see this page about Breeding .

3 Prescribing antibiotics after castration surgery Other web pages on neutering cavies advise strongly against the use of antibiotics as a preventative measure after surgery. We disagree with this position and know of a number of cases where had antibiotics been prescribed, lives could have been saved. The downside risk of prescribing antibiotics after a neutering procedure on a guinea pig is insignificant (maintaining gut flora is manageable) compared to the much higher risk of infection after a cavy neuter. Cavies are low to the ground and live, walk, and sleep in loose bedding contaminated with feces and urine and food. Prepping the area for surgery is also difficult. All it takes is one little hair to get caught in the suture. It's easier to prevent an infection after surgery than it is to treat it later. Some bacterial infections can go unnoticed resulting in systemic infection and death. Please note: This page is a collaborative effort by no less than four guinea pig rescuers across the US with extensive experience in neutering hundreds of guinea pigs over time, including one RVT (a Registered Veterinary Technician) and the contribution from two DVMs (veterinarians) on a protocol example.

In addition, a number of highly regarded exotic vets have been interviewed to make sure all information presented is as correct as possible. On This Page Guinea Lynx :: Reproduction REPRODUCTION Reproduction and Breeding Pregnancy and delivery are difficult for guinea pigs. The babies are born large, fully furred, and ready to run. The mother generally carries several pups and her weight may double, putting stress on her circulation system and other organs. Even with the best care, sows can suffer from dystocia, hypocalcemia, a prolapsed uterus, or pregnancy toxemia. For the health and well-being of your beloved pet, do not breed! Near the end of her pregnancy, Dutchess (a rescue) could barely move. She delivered 6 pups in a back-to-back pregnancy. Thanks to mmercedesmom for the photos of Dutchess. If you have accidentally purchased a missexed pair of guinea pigs and the sow is pregnant, remove the boar immediately. A sow that has just delivered can become pregnant soon after giving birth. A male guinea pig must not be present during the birth for this reason. Back-to-back pregnancies are extremely hard on a female guinea pig and not advised.

See Also: Length of estrus cycle: 15-17 days Milk Composition: 3.9% fat, 8.1% protein, and 3.0% lactose Earliest Reproductive Age - Female 4 weeks Earliest Reproductive Age - Male 3 weeks Remember: Female guinea pigs can be sexually mature as early as 4 weeks of age. Given the early ages at which some males and females are sexually mature (females have reportedly been impregnated by 24 day old males), it is advised to remove the male young by 3 weeks at the latest. The earliest dates of sexual maturity are reported by V.C.G. Richardson in the 2000 edition of "Diseases of Domestic Guinea Pigs" on page 15: Sexual maturity (female): 4-6 weeks Sexual maturity (male): 3-5 weeks While not all males may be fertile this early, the safest action is to separate the males from females by 3 weeks of age. Pregnancies of very young sows are also difficult for the animal. Food for her developing and maturing body is diverted to the young fetuses.

While intentional breeding is never recommended, young guinea pigs can successfully carry to term. Too often pet stores mix sexes, resulting in unintentional pregnancies. Breeding after 8 months of age can be fatal for a guinea pig that has not had a previous litter due to dystocia. The symphysis (a joint of tough fibrous cartilage which firmly joins the 2 pubic bones) becomes less flexible upon reaching adulthood and may not separate fully, making delivery difficult. Harkness and Wagner in The Biology and Medicine of Rabbits and Rodents describe how the pubic symphsis begins to separate late in the pregnancy due to the hormone relaxin. About 48 hours before birth, you may be able to feel a gap of 15mm or so. At birth it can increase to 2.5 cm (1-1.5"). "If the first breeding is delayed past 7 or 8 months, the symphysis separates less easily, and fat pads occlude the pelvic canal. Such impediments may lead to dystocia and death, especially when small litters of large young are involved)." Sows with dystocia usually need a caesarian section. The survival rate is very poor.

Spaying or neutering guinea pigs also carries risks even when performed by an experienced guinea pig veterinarian. The safest choice is to keep the sexes separate or have only sows or boars. Sows who become pregnant at an older age can sometimes deliver successfully but because of the added risks, pregnancies should be avoided. All pregnancies carry risk. If your older sow has become pregnant, the safest course is to allow the pregnancy to procede normally but line up an experienced vet in case there are complications. Another alternative is terminate the pregnancy. All surgery also carries risk. Estrus Harkness and Wagner in The Biology and Medicine of Rabbits and Rodents state that the estrus cycle in guinea pigs is 15 to 17 days. Since most sows will have an estrus (a time when they can become pregnant) from 2 to 15 hours immediately after giving birth, remove any boar from the cage as the delivery date approaches to prevent back-to-back pregnancies which would be physically stressful for any sow. They claim the estrus period occurs for 24 to 48 hours, 6 to 11 hours of which the female will accept the male.

According to Pinta: "Your pig is in estrus when the mucous plug is dissolved. The plug seals the vaginal opening when she is not in estrus. The plug will dissolve approximately every 10 to 21 days. To check if it's dissolved, just see if the top of the "y" is separating to create an opening. It's open approximately for 24 hours and then it starts to close or plug up again." Every pregnancy caries risks: pregnancy toxemia and dystocia can be life threatening. Clinical signs of pregnancy toxemia: The sow stops eating, becomes depressed, and adopts a hunched, ruffled appearance. She may salivate profusely and the characteristic smell of ketones can be detected on her breath as she becomes ketoacidotic. The condition progresses to muscle spasms and death. The signs often occur abruptly. Pregnancy toxemia is more prevalent in hot weather.

Question: What name is given to a male guinea pig?
Answer: Boar