Help animal first (6)
I believe the answer is:
assist
'help' is the definition.
(assisting is a kind of helping)
'animal first' is the wordplay.
'animal' becomes 'ass' (I've seen this before**).
'first' becomes 'ist'.
'ass'+'ist'='ASSIST'
(Other definitions for assist that I've seen before include "Expedite" , "Give a hand to" , "Support" , "Give help" , "Aid, abet" .)