Guinea pigs are docile animals, and rarely bite without cause. They tend to 'mouth' their owners while being held, just to see if you’re edible! These are not hard bites, though, and don't hurt. It's not aggression, just curiosity.
Guinea pigs only use their teeth aggressively if they feel under threat - they are their only means of defence. If your pet bites you for real, it’s because they’re afraid of you. Teaching them that they don'y need be afraid, and that they can actually expect treats and affection from you is what this training is all about.
Guinea Pigs don't usually use their teeth aggressively
How to stop your guinea pig biting
You need to figure out why your pet is biting in the first place. There are different possible reasons:Fear
Do you smell of something that your guinea pig might be afraid of, such as cats and dogs? Wear clean clothes and wash your hands before you pick them up. It's a good idea to wear gloves - clean ones - to offer protection in case the GP still wants to bite. Or perhaps the GP is stressed, and therefore afraid. Are they in a noisy place? Do they feel threatened by other pets, noisy children, or noisy household appliances?Pain
Another thing that causes a GP to bite is if it's in pain. Are you holding too tightly? Is the guinea pig ill or injured? Give them a quick health check to see if they need to visit a vet. If they have the skin disease mange, it can make handling painful for them, and they have no way of telling you not to pick them up other than biting.Calls of Nature!
It's possible that your guinea pig wants to be put down because it needs to go to the bathroom and can't wait! In this case it may nibble irritably on your hand to let you know. When you put your guinea pig down, watch it to see if this is indeed the case.Living Conditions
Another possible reason for a guinea pig biting is to do with the animal's environment. If it chews its bars all the time, it can indicate loneliness. If you only have one guinea pig, then even if you’re the most affectionate owner in the world then it will still be lonely without a guinea pig companion. Alternatively, it could be because you haven't cleaned out the hutch and the animal is getting stressed by the soiled bedding.Testosterone
Another potential cause, amongst male GPs, is testosterone. If if your guinea pig isn’t neutered, he may turn aggressive. You might want to consider neutering him, but need to be aware that this is actually no guarantee that he will change his behavior.