Looks great, though I find the whistle sound toooooo high-pitched and hurts my ears having to hear it many times. I find that a lot of times the white sheep would get stuck at a corner and there's no way for me to get them out.
I do like the concept and visuals though, kudos to that! Though, with regards to the "Out of Control" theme it does feel like I'm controlling things most of the time. Just something to take note of!