Golden MacDonald

The metaphor breaks down when you examine it.

The shepherd is explicitly a boy, though it's not clear exactly how old he is. The sheep is an actual sheep, and not even a particularly useful one at that (black wool was less desirable). And I've read "Where the Red Fern Grows"-- I know that in a battle of dog vs. mountain lion, mountain lion usually wins.

Message

Sheep are worth risking your life over.