That protects the guinea from being accidentally dropped and the child from being scratched. When you make a commitment to care for a guinea pig, you also commit to keeping it as healthy as possible. Guineas sometimes do need to see the vet, particularly if they show signs of skin disease or respiratory illness. Another sign of trouble is a loss of appetite. Most small animals are very good at hiding pain and their reluctance to eat is usually the first clue that something is very wrong.
Diarrhea is a bad sign and can lead to dehydration.
Sometimes food is the culprit - if you've recently given your cavy a new vegetable or treat, it might be the cause. Try taking away wet food for a day to see if it clears up. If you can't trace the problem to a food-related source, it's time to see the vet. As a pet owner, attention to your guinea pig's routine is the best way to catch a problem. Changes in eating, elimination, coat or breathing can all be reasons for concern.