Actually, I've noticed this behaviour with my cats too. If there is a reptile tail sticking out, they have this need to try and chew on it if I'm not looking.
Mirage came out of brumation on April 26. He was doing great. On May 2 he started acting funny. We just redid his tank, and he keeps going into one of his hides. He just lays there. He shows no intrest in food. HELP!