This is an amazing documentary that follows a puppy from a week old up through guide dog training. This dog is a yellow lab, and the focus is on this dog plus four others--a spaniel, a shepherd, a mix, and another lab--but as the documentary covers information about dogs, it uses many different breeds.
It's a half-hour long.
https://www.youtube.com/watch?v=UxqRw-bo84I
Fascinating. You won't be bored if you're a dog lover.