Guinea Pigs
Housing
Housing accommodations provided for pet guinea pigs are limited only by one’s imagination, ingenuity and budget. There is no single correct way to house your guinea pig as long as the wellbeing of your pet is considered. Adequate housing is a major factor in the maintenance of healthy pets.
Guinea pigs can be housed within enclosures made of wire, stainless steel, durable plastic or glass. The latter three materials are preferred since they resist corrosion. 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 design and construction of the enclosure must be escape-proof. In addition, the cage must be free of sharp edges and other potential hazards. The size of the enclosure should allow for normal guinea pig activity. Approximately 100 square inches of floor area per adult guinea pig is recommended. Breeding animals should be provided 180 square inches each. 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. Housing on wire over long periods of time often results in foot pad and hock infections from abrasive rubbing on fecal soiled wire. To reduce the incidence of these problems, provide a solid platform as a resting place in one area of the cage. Broken legs are common in guinea pigs that fall through the wire mesh and panic to escape. Although solid flooring requires more effort to keep sanitary, it is safer for the guinea pig. Solid floor cages also tend to be more esthetically pleasing when appropriate bedding is used.

Bedding materials must be clean, nontoxic, absorbent, relatively dust free and easy to replace. Acceptable beddings are wood shavings, shredded paper, processed ground corncob and commercial pellets. Make sure the ground corncob is properly processed and stored to reduce fungal spore problems. Cedar shavings have been associated with causing respiratory difficulty and liver disease in some guinea pigs, so 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.

The environment in the vicinity of the pet’s cage is another important consideration. Because of their sensitive nature, guinea pigs are more comfortable and relaxed when housed in a quiet spot away from noise, excitement and other such stresses. Also be sure to select a location away from direct sunlight and avoid cold, damp areas. Guinea pigs thrive in a dry, cool environment with adequate ventilation. 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 to rest.

Since guinea pigs are social creatures, more than one animal may be safely housed together. In addition, 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 cage mates.

Breeding
The single most important consideration regarding guinea pig breeding is that 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 much beyond this time, serious and often fatal problems with delivery may result. The reason for this is that the pelvis of the guinea pig fuses at this early age, which narrows the birth canal, preventing the babies from passing easily. Males (boars) should be at least four months of age before breeding.

The sow’s estrous cycle (“heat”) lasts 14 to 19 days. The actual 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 time is known as “postpartum estrus”, which means that she can be nursing one litter while being pregnant with another.

Pregnancy lasts between 63 and 70 days. The gestation is shorter with larger litters, and longer with smaller litters. This duration of pregnancy is relatively long when compared to other rodents.

Pregnant sows exhibit a grossly enlarged abdomen during the later stages of pregnancy. Her body weight may actually double during pregnancy. The time of delivery is difficult to assess in guinea pigs due to the relatively long gestation period and lack of nest building by the sow. Within one week prior to delivery, a slight widening of the pelvic area can be noted. This is the separation of the pelvis, which if does not occur can cause the delivery problems mentioned previously. If the pelvis does not separate, as in sows that are bred past seven months of age, delivery of the young may be impossible without a cesarean section.

An 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. First time litters are usually very small. Unfortunately, abortions and stillbirths are not uncommon with guinea pigs.

The young are very well developed at birth. They weigh between 50 and 100 grams and have a full hair coat. Babies are even born with teeth and with their eyes opened. Mothers are not very maternal in the raising of the offspring in that she does not build a nest and even remains in a sitting position while nursing. 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.
© 2004 Midwest Bird and Exotic Animal Hospital