Useless in pet management (5)
I believe the answer is:
inept
'useless' is the definition.
(I've seen this in another clue)
'in pet management' is the wordplay.
'management' is an anagram indicator.
'pet' is an anagram of 'ept'.
'in'+'ept'='INEPT'
(Other definitions for inept that I've seen before include "Maladroit" , "Futile" , "Awkward, showing no skill" , "Incompetent or awkward" , "Silly or senseless" .)