No sheep here, but I've seen BCs work sheep. While driving down a back country road I approached a flock of sheep, their owner in front on horseback, two BCs bringing up the rear. Both sides of the road were fenced. When this slow moving parade reached a church yard, the owner twisted in the saddle, whistled and motioned with his arm for the BCs to move the sheep into the church yard. They did and held the sheep there until I passed.