I have two large dogs as you can see. The black one is Sammy a black Lab. 90 pounds.  The white one is a Great Pyreness which most of you have not seen or know about. Her name is Wendy.  She weights 120. Both are very loving dogs.  Sammy loves all but if attack by another dogs he is toast. Wendy I trust with an any one all dogs and people.  Hell I trust her with a baby she smells them not lick them. Great Pyreness are breed to protect, you can not train them to be attack dogs. They are breed to protect a flock of sheep or a flock of cattle or a flock of goats, or any herd that is put in front of them to protect.  That is there job in which they were breed for. To Wendy me and Sammy are her flock. This is so strange, I have dogs all my life and they bark at anything they see on the ground. I sure you have sure such a dog. But  Since I got Wendy I have never seen a dog to bark at a hawk  who sources high in the sky above.
She does it to  protect us.  Enough said, if some dog get a ideal to attack Wendy, well its toast for them.
 I have see it twice and in 20 seconds they are hurt and running. Well sorry for the long about me.
I hope you understand Great Pyreness better now. Like the Lab they have a short name to,  they are call Pyres, (think of a fishing pier)