is my rat dying?

Question
my rat bernard is a little over a year old. Lately he has not been himself: when i let him loose he runs around but not with the vivacity he usually does. He spends a lot of time sleeping, and seems to have a loss of appetite. He is usually full of energy and very outgoing. Almost suddenly this has declined. We did get a new kitten (we already have 2 cats which he is friends with :) ) but she doesn't bother him. I thought it was the cold weather so i moved him next to a heater and put extra blankets in his hammock. Is he just getting old?

Answer
Without any definite symptoms, it's really hard to say if he's sick or just slowing down. If he's a pet store rat, odds are he's probably reached that "old age" gray area. Encourage him to eat by keeping meal times fun, changing up his usual food with some new treats or add in a colorful, low-sugar cereal. If you notice any other symptoms from him at all, get him to the vet and have a full wellness check on him.