Handling and Restraint: Guinea pigs rarely violently struggle when they are being picked up but often make a "squeal of protest," which sounds pig-like to many people. Nevertheless, great care should be taken not to injure them when picking them up. The guinea pig should be approached with 2 hands. One is placed under the guinea pig's chest and abdomen, and the other supports its hindquarters. Adults and those that are pregnant should receive gentle, but firm, and total support. One of the most desirable features of guinea pigs as pets is that they rarely bite when being handled or restrained. One reference indicates that only 1 in 400 will bite under these circumstances.
Housing: Proper housing is a major factor in the maintenance of healthy guinea pigs. The well-being of the animals must be a primary consideration. Guinea pigs can be housed within enclosures made of wire, stainless steel, durable plastic, or glass. The last 3 materials are preferred because they resist corrosion. Wood and similar materials should not be used in construction of enclosures because they are difficult to clean and cannot withstand gnawing. The construction and design of the enclosure must prevent escape. The enclosure also must be free of sharp edges and other potential hazards. The enclosure must be roomy enough to allow normal activities and breeding, if the latter is desired. One reference recommends at least 100 square inches of floor area per adult, whereas breeders should be allowed 180 square inches per animal. The enclosure can be open at the top, provided that its sides are at least 7-8 inches high. Male guinea pigs (especially breeding males) require enclosures with sides at least 10 inches high. Males tend to be more rambunctious.
Guinea pigs can be housed on wire mesh (suitable for housing rats) but it is not recommended. Though wire mesh allows urine and most fecal pellets to drop through, thereby keeping the bedding and the residents cleaner, guinea pigs housed for long periods on wire tend to develop serious injuries to the bottoms of their feet (see section on Foot Pad Infections). Furthermore, a leg maybe broken if it becomes entangled in the mesh. This is most often a problem with guinea pigs that have not been reared on wire mesh, and occurs soon after they have been introduced onto it. Enclosures that provide solid flooring and an adequate supply of a preferred bedding are best for pet guinea pigs. They should be easy to clean, well lighted, and adequately ventilated (see Vital Statistics for preferred temperature and relative humidity ranges). Bedding must be clean, nontoxic, absorbent, relatively dust-free and easy to replace. Shredded paper, wood shavings, and processed corn cob are preferred bedding materials. Sawdust should be avoided because it tends to collect within the external genitalia of males, forming an impaction. Rarely does this impaction interfere with urination, but it may inhibit successful breeding. Cedar shavings should also be avoided because the pleasant smelling odor they impart to the cage are actually toxic to the animal.
Guinea pigs seem most comfortable when they are spared exposure to excessive noise, needless excitement and other stresses. Sudden movement should also be prevented. Guinea pigs have 2 types of reactions when startled by a loud noise or sudden movement or when placed in a strange environment. They may "freeze" completely motionless (for up to 20 minutes), or they may panic. Panic involves erratic running and leaping, often accompanied by shrill squealing. Groups of guinea pigs may stampede in a circle, often trampling the younger residents within the enclosure. A panic reaction scatters bedding and food, fouling the food and water containers. Visual security (a place into which they can retreat when frightened) should always be provided. Rectangular enclosures containing barriers also reduce the tendency to stampede and circle.
Hygiene: The frequency with which the enclosure is cleaned depends on its design, the materials out of which it is made, and the number of guinea pigs that reside within in. As a general rule of thumb, the enclosure and all cage "furniture" should be cleaned and disinfected once weekly. Food and water containers should be cleaned and disinfected once daily. More than one set of containers should be maintained, and the soiled set should be washed in a dishwasher, if possible. Vigorous scrubbing of the enclosure and "furniture" with hot water and soap and a thorough rinse should be followed by use of a disinfectant (Roccal-D: Winthrop). Vinegar is often required to remove the scale deposited by the crystalline urine of guinea pigs.