Is Takeo new? Was it shivers not shaking? If it was shivers it was nerves and a lot of rats will do that when they are uncertain in a situation. New rats do this often.
If it was shaking, with the paws and body jerking, and a fixed attitude, then he shook himself and was fine? Could be a seizure. If it was rythmic back and forth movements it could've been him hiccupping.
If it was shaking, with the paws and body jerking, and a fixed attitude, then he shook himself and was fine? Could be a seizure. If it was rythmic back and forth movements it could've been him hiccupping.