The guinea pig or cavy is a docile rodent native to the Andes Mountain area of South America.

Guinea pigs are found in four major coat types. The Shorthair or English is characterized by having a uniformly short hair coat. The Abyssinian has whorls or rosettes in their short, rough, wiry coat. The Silky is distinguished by its medium length silky hair. The Peruvian is recognized by its very long silky hair.

Basic Facts of Guinea Pigs

Scientific Name Cavia Porcellus
Life Span 4-5 yrs.
Environmental Temperature 65-75 degrees Farenheit
Optimal Humidity 40-70%
Breeding Age (1st mating) 3-4 mnths male

3-7 months female

Litter Size 1-6 range

3-4 avg.

Weaning Age 3 weeks


Good quality food and fresh, clean water must be readily available at all times. Pelleted chows provide all the essential nutrients required by guinea pigs as long as the pellets are fresh. Guinea pigs cannot manufacture their own vitamin C, therefore they must receive it from an outside source. Pelleted guinea pig diets are supplemented with Vitamin C, however, they lose the vitamin C rapidly after manufacture. Therefore we recommend vitamin C supplementation in the water as follows : 100 milligrams ascorbic acid (human vitamin C syrup or soluble tablet/capsule) added to 1 cup of drinking water, made up fresh every 12 hours. Alternatively, a guinea pig can be offered one handful of fresh kale, cabbage or other dark leafy green high in ascorbic acid.

Do Not feed rabbit pellets as a substitute for guinea pig pellets. They are not equivalent in nutritive value.

Additions to the guinea pig’s diet should be made carefully and slowly due to their sensitive digestive system. The majority of the diet, at least 80-90%, must be the balanced ration (guinea pig pellets). A small amount of kale, cabbage, or orange can be fed as a vitamin C supplement. In addition, fresh greens, timothy / grass hay, and small amounts of fruit may be offered daily. These foods should not make up more than 10-15% of the daily consumption. Furthermore, the fresh items must be thoroughly washed to avoid exposing your pet to pesticide residues or bacterial contamination. Feeding bowls should be heavy ceramic crocks that resist both tipping and chewing. They should be high enough to keep bedding and fecal pellets out of the food but low enough for easy access by the animal.

Water is most easily made available by the use of a water bottle equipped with a “sipper” tube.All food and water containers be cleaned and disinfected daily.


Guinea pigs can be housed within enclosures made of wire, stainless steel, durable plastic, or glass. Wood should not be used due to difficulty in cleaning and susceptibility to destructive gnawing. Ideally, the enclosure should have one side open for adequate ventilation, so be careful when using aquariums. The cage must be free of sharp edges and other potential hazards. The size of the enclosure should allow for normal guinea pig activity. A minimum of 200 square inches of floor area per adult guinea pig is recommended. The enclosure can remain opened on the top if the sides are at least 10 inches high (as long as other family pets such as dogs or cats are not a threat).

Cage flooring can be either wire or solid. Wire mesh flooring provides a cleaner environment and easier maintenance but may result in injuries to the feet and hocks. To reduce problems provide a solid platform in one area of the cage.

Bedding materials must be clean, non toxic, absorbent, relatively dust-free, and easy to replace. Acceptable beddings are wood shavings, shredded paper, processed ground corn cob, and commercial pellets. Cedar shavings have been associated with causing respiratory difficulty and liver disease in some guinea pigs and thus should not be used. Saw dust should also be avoided since it tends to accumulate within the external genitalia of male guinea pigs causing an impaction.

Keep the cage in a dry, cool, well ventilated and quiet spot away from noise, excitement, and other stresses. Avoid direct sunlight and cold damp areas. Drastic environmental changes should be prevented (especially high temperatures and humidity). Since they are nocturnal (active at night), guinea pigs require quiet periods of light in order to rest.

Guinea pigs may be safely housed together. Males and females can remain in the same enclosure indefinitely. However, new males may occasionally fight if in the presence of a female. Older, dominant animals may also chew on the ears or hair of subordinate cagemates.


The female guinea pig (sow) should be bred between four and seven months of age if she is to be bred at all. If the first breeding is delayed beyond this time, serious problems with delivery may result due to the narrowing of the birth canal after this age… Males (boars) should be at least four months of age before breeding.

The sow’s estrus cycle (“heat”) lasts 14 to 19 days. The period in which the sow is receptive to the boar for breeding is approximately eight to fifteen hours during this cycle. Sows often return to “heat” within a few hours after giving birth. This means that she can be nursing one litter while being pregnant with another.

Pregnancy lasts between 63 and 70 days . n uncomplicated delivery usually takes about one-half hour with an average of five minutes between babies. Litter sizes range between one and six with an average of three to four.

The young are very well developed at birth with eyes open and a full hair coat. Mothers are not very maternal in the raising of the offspring in that she does not build a nest. The young can actually eat solid food and drink from a bowl shortly after birth, but it is recommended to allow them to nurse for three weeks before weaning.


Slobbers / Dental Malocclusion

Slobbers is the condition where the fur under the jaw and down the neck remains wet from the constant drooling of saliva due to poor alignment and overgrowth of the cheek teeth. Most often this occurs in older (2-3 years of age) guinea pigs. Excess selenium in the diet may also play a role in this problem.

The diagnosis is confirmed by visual examination of the mouth by your veterinarian. Correction of the problem involves trimming or filing of the overgrown teeth (usually requiring general anesthesia). A correction of the diet may also be in order if an elevated selenium level is suspected. In addition, force feedings and antibiotics may be necessary to aid in the recovery.

Scurvy (Vitamin C Deficiency )

Guinea pigs cannot manufacture Vitamin C and must receive a supply from outside food sources. Lack of sufficient Vitamin C in the diet results in scurvy. The symptoms include poor appetite, swollen, painful joints and ribs, reluctance to move, poor bone and teeth development, and spontaneous bleeding especially from the gums, into joints, and in muscle. If left untreated, this disease can be fatal especially to rapidly growing young and pregnant females. Treatment is based on vitamin C supplementation and correction of the diet.

Barbering (Hair Chewing)

Barbering occurs when guinea pigs chew on the hair coats of other guinea pigs that are lower than them in the social “pecking order”. The dominant “pig” is identified by its normal, full hair coat while others have areas of hair loss. Treatment requires removal of the dominant pig.

Heat Stress (Stroke)

Guinea pigs are very susceptible to heat stroke, particularly those that are overweight and/or heavily furred. Environmental temperatures above 85 degrees, high humidity (above 70%), inadequate shade and ventilation, overcrowding, and other stresses are additional predisposing problems. Signs of heat stroke include panting, slobbering, weakness, reluctance to move, convulsions, and ultimately, death. This is a treatable condition if recognized early. Heat stressed guinea pigs should be misted with cool water, bathed in cool water, or have rubbing alcohol applied to its footpads. Once this first aid measure is accomplished, veterinary assistance should be sought.



Pneumonia (an infection in the lungs caused by bacteria or virus) is a common disease of the guinea pig. Conditions of stress, inadequate diet, and improper husbandry will often predispose a pet to pneumonia. Symptoms include difficulty breathing, discharge from the nose and eyes, lethargy, and inappetance. In some cases, sudden death will occur without any of these signs. Occasionally, middle or inner ear infections accompany respiratory disease in guinea pigs. Additional symptoms in these cases include incoordination, twisting of the neck (torticollis), circling to one side, and rolling.

Veterinary consultation should be sought when a guinea pig exhibits any of the above symptoms. A bacterial culture with antibiotic sensitivity of the throat or nasal discharge will assist in the selection of an appropriate antibiotic. Aggressive antibiotic therapy in addition to supportive care of the patient may be necessary to get the condition under control.

Bacterial Enteritis (Intestinal Infection)

A number of bacteria are capable of causing infections of the gastrointestinal tract in guinea pigs. Some of these bacteria are introduced through contaminated greens or vegetables or in contaminated water. In addition to diarrhea, common symptoms are lethargy and weight loss. In other case, sudden death may occur before expression of these signs.

A veterinarian may elect to use aggressive antibiotic therapy and supportive care to treat this condition. A bacterial culture of the patient’s stool with antibiotic sensitivity will greatly assist the veterinarian in choosing an appropriate antibiotic to use.

Bacterial Pododermatitis (Footpad Infection)

Severe infections of the footpads (front feet most commonly) are very common among guinea pigs housed in cages with wire flooring. Fecal soiling of the wire potentiates the problem. Symptoms of this condition include swelling of the affected feet, lameness, and reluctance to move. Improved sanitation and cage floor alterations are the initial steps in correcting the problem. The feet should be treated by a veterinarian. Prolonged treatment with bandaging and antibiotics is often required.

External Parasites (Lice and Mites)

Lice and mites are the most common external parasites of guinea pigs. Lice insects that live within the hair coats of infested animals. Both adults and eggs are found attached to hair shafts of affected pets. Mites are microscopic, spider-like organisms that infest the top layers of the skin in affected animals. Guinea pig lice and mites are not known to parasitize man.

Mite infestations are usually more severe than lice. The sarcoptic mite lives in the outer layers of skin causing an intense itching and scratching with considerable hair loss. Transmission of mites can occur only through direct contact between infested and noninfested guinea pigs. Therefore, pet guinea pigs are not likely to harbor this parasite unless they are recent additions or had previous exposure to mite-infested guinea pigs. A veterinarian can diagnose lice and/or mite infestation by performing skin scrapings of affected areas and viewing them under the microscope. Successful treatment of mites consists of one to four injections at two week intervals. In the meantime, if wood shavings are used as bedding or litter, it should be replaced with paper toweling to make your pet more comfortable. Treatment of lice may require topical treatment w/ special shampoo or dips.

Guinea Pig Sensitivity To Certain Antibiotics

Guinea pigs are very sensitive to certain classes of antibioticsMany antibiotics have been shown to be lethal to guinea pigs including: ampicillin, penicillin, bacitracin, gentamicin, erythromycin, lincomycin, clindamycin, streptinomycin, vancomycin, and sometimes tetracyclines. Even if an antibiotic is not on this list, it does ensure that it is safe to use. The primary cause of this lethal side effect is a dramatic alteration of the normal microbial balance in the digestive tract .

For this reason, NEVER attempt treatment of your pet guinea pig at home without prior consultation with our veterinarians. For the surrounding communities of Alta Loma, Rancho Cucamonga, Upland, Ontario, Claremont, Fontana, and the Inland Empire, call (909) 980-3575 to make an appointment.