Televised cockney's healthy dog (8)
I believe the answer is:
airedale
'dog' is the definition.
(Airedale is an example)
'televised cockney's healthy' is the wordplay.
'televised' becomes 'aired' (I've seen this in another clue).
'cockney's healthy' becomes ''ale' ('hale' - similar in meaning - said with the 'H' dropped - a cockney accent.).
'aired'+'ale'='AIREDALE'
(Other definitions for airedale that I've seen before include "Yorkshire valley" , "Yorkshire district; breed of terrier" , "Canine breed" , "Thematic type [DOG]" , "River valley; rough-coated terrier" .)