We had a border collie when the kids were little. In the absence of sheep, she kept them where we wanted them. Then she had a daughter to a bearded collie - turned into a sort of affectionate floor mop, but an excellent mouser, who disposed of the evidence completely in one bite.

Our current Border x black retriever is more of a retriever than a rounder up - she got a mouthful of baby jackdaw, brought it to us and spat it out alive and intact.
She also had a phase of retrieving all the hedgehogs in the garden for us - but eventually the penny dropped, and she stopped bleeding.

Paws