Animal docs (4)
I believe the answer is:
vets
'animal docs' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for vets that I've seen before include "Animal surgeons" , "old soldiers" , "13 doctors?" , "Investigates thoroughly to ensure suitability, for a job perhaps" , "Examines the animal doctors carefully?" .)