guinea pig laying around for several days

Question
i have a 1 1/2 yr old male guinea pig. usually he is bouncing around his cage, but for the last 4 days he has just been laying around. he is eating and drinking okay, and pooping okay. could he be sick or something? please help...

Answer
The best and most dependable symptom of how a guinea pig feels is whether or not he's eating and drinking.  He's still a young animal and if he's eating okay I can't help but think he's probably just lazy right now.  Mine always nap in the afternoon. It's a ritual they all hold onto. When the weather changes their activity level sometimes changes as well.  Just as with humans, if it's hot and humid we don't want to move around much.  So maybe he's just got the lazies, perhaps due to weather changes.

Feel his flesh around the backbone and rear. When a pig begins to feel poorly they often start to lose weight, even though they may still be eating a bit.  As they get on in years and are nearing the end they get what breeders and vets call 'wasting.'  You can feel their backbones and you can see a weight loss even in the face. But that's an old age symptom, not what you're describing here.  

I don't see anything that tells me he's ill. He's taking food in and putting it out. This is very likely just a temporary thing.