Sounds like it's time to call the vet. Unfortunately, feeder mice tend to get a lot of health problems. Has he been drinking at all? Urinating? No one can really diagnose him over the internet.just one more question, i have them living alone...which has been good so far...but one more issue has me worried. i have one mouse (gorilla) he's a feeder mouse. i feel like when i hold him he's dehydrated or something. he doesn't feel like he used to. he rarely comes out of his house and i'm worried he isn't eating or drinking right....what do i do?