I know Karelian Bear-Dogs, norwegian elkhounds, Catahoulas, etc will defend their owners against most everything
I don't know if they'd survive wolf packs? But..does anything? I read that someone was out hound hunting and the wolf pack killed all his dogs. The last dog that was alive turned around and defended her owner and was killed herself. I don't know if the wolves went after him or she just stood her ground so he could get to his truck. Long story short - The wolves killed his whole pack of dogs.