Dog in show put on lead, barking with energy (8)
I believe the answer is:
airedale
'dog' is the definition.
(Airedale is an example)
'show put on lead barking with energy' is the wordplay.
'show' becomes 'air' (both can mean broadcast).
'put on' is a charade indicator (letters next to each other).
'barking with' is an anagram indicator ('barking' can informally mean mad).
'energy' becomes 'e' (physics symbol as in E=mc2).
'lead' with its letters anagrammed with 'e' gives 'edale'.
'air'+'edale'='AIREDALE'
'in' acts as a link.
(Other definitions for airedale that I've seen before include "A leader I turn into a large breed of dog" , "Yorkshire valley" , "River valley; rough-coated terrier" , "Terrier - Yorkshire area" , "best friend?" .)