Dog, say, shakes with abdominal pain (12)
I believe the answer is:
collywobbles
I'm afraid I can't explain this answer.
Can you help me to learn more?
(Other definitions for collywobbles that I've seen before include "Intense anxiety" , "Owls by Belloc (anag) -- severe gastroenteritis" , "Feeling of apprehension" , "Nervous apprehension" , "Upset stomach" .)