Before you start complaining to me, let me state I am not entirely convinced either. I just want to share the robot technology with you.
Here is the text that came with the fragment at YouTube:
"Physiological stress measurements were done with manual shearing. Separation from other sheep is more stressful than shearing. Most stressful thing for sheep is, apparently, copulation, and no one has been able to demonstrate harmful after-effects. (Thanks to Prof. Emeritus. David Lindsay). In our tests, sheep often fell asleep and showed no signs afterwards of any ill-effects from being constrained."