Guinea pigs are very effective communicators and are capable of alerting their owners to many of their needs, from hunger to pain to the need to urinate or defecate. Once you know what signs to look for, you won't be surprised to see that your cavy needs to take a bathroom break.
Most guinea pigs enjoy being cuddled by their owners outside of their cages. Holding and stroking your guinea pig encourages bonding between the two of you and most guinea pigs will relax and enjoy the attention. But if you notice that your cavy is starting to become restless and begins to fidget while you are holding him, it most likely means he needs to go to the bathroom. Return him to his cage at this point to allow him to relieve himself.
Guinea pigs are docile creatures by nature and tend to only bite their owners if they are trying to communicate a specific need to them, like the need to use the bathroom. Guinea pigs prefer to relieve their bladders in an area in which they can have some semblance of privacy rather than on their owners. They will lightly bite their owner if they are being held and want to be returned to their cage to urinate. The longer you ignore this signal, the more forceful your cavy might become with his bite. If you continue to hold him, he may end up relieving his bladder on your clothing.
Guinea pigs approach the area in which they intend to defecate by backing into it while slightly raising their hind quarters. If you have your pet out on the floor, engaging in some playtime, and you see him run over to a corner or particular area and start to back up, odds are he will be leaving behind some feces and maybe even a little urine on the floor.
Scene of the Crime
Guinea pigs are members of the rodent family and, as such, will tend to designate one specific space inside their habit as the toilet bowl area. If you see your cavy heading over to that section of his living quarters, chances are he is going there to relieve himself. Because this area will be used repeatedly, you must keep it clean at all times by replacing the soiled litter and any other materials you might be using as part of the living quarters' floor.
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