Long-haired sheepdog (6)
I believe the answer is:
collie
'long-haired sheepdog' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for collie that I've seen before include "Farm dog" , "Type of sheepdog" , "Silky-coated sheepdog" , "Breed of dog" , "Sheepdog wth ling nose and shaggy hair" .)