Animosity in dog when picked up? (5)
I believe the answer is:
pique
'animosity' is the definition.
(I've seen this before)
'dog when picked up?' is the wordplay.
'dog' becomes 'peke' (short for Pekingese).
'when picked up?' indicates a 'sounds like' (homophone) clue (pick up can mean to hear).
'peke' sounds like 'PIQUE'.
'in' is the link.
(Other definitions for pique that I've seen before include "Petulant anger" , "Irritation, resentment" , "Animosity" , "Stimulate (one's curiosity)" , "Bad temper" .)