Nowadays pet management is clever (5)
I believe the answer is:
adept
'clever' is the definition.
(adept can mean clever or expert)
'nowadays pet management' is the wordplay.
'nowadays' becomes 'AD' (AD, Anno Domini, as opposed to BC, Before Christ).
'management' is an anagram indicator.
'pet' anagrammed gives 'ept'.
'ad'+'ept'='ADEPT'
'is' is the link.
(Other definitions for adept that I've seen before include "Deacon" , "Practised" , "Proficient, skilled" , "Very skilful, proficient" , "Handy" .)