Sheepish faces

It was established a few years ago that sheep could recognise up to 50 familiar faces of other sheep, and of their human handlers too  (see this blip),

More recently it's been shown that they can quickly learn to distinguish between human faces in an experiment which had them getting a reward  for picking famous faces rather than random ones. (The famous faces included Baarack Obaama's - scientists do like to have their little jokes.)

My query is, how easy is it for us to recognise the faces of individual sheep? There are five here (one got in twice) and they all seem very different. Of course, that may be because , apart from the piggy-faced one bottom right, they belong to a hobby flock who enjoy a peaceful privileged lifestyle rather than commercial farm stock who receive scant nurturing.

Tradiitonal shepherds knew their animals individually and would have no problem spotting which one was missing or unwell but generally speaking those skills have been lost since round-ups are done with mechanised vehicles instead of on foot with a crook and a dog.

Extra: handsome profiles