Having a well trained and trustworthy seasoned dog around when you get a new pup has been very successful for me.
Old Momo, (Ausie) helped train by example, the three guardian dogs I have now.
Momo was a purebred given to us for free as he was considered a undesirable color. He was a constant companion to my daughter growing up and I am sure he woud have gladly died for her. He was a master guardian dog, sniffing the wind, and off like a shot if he heard or smelled something that was trouble.
He had no formal training for this. He just came by it natural.
My dogs now are MIKI (border collie/blue heeler,
JUNE (german shepherd/lab,
and ZIP (pit bull/Australian shepherd.
June was 5 when we rescued her. She had a history as a killer of poultry, but she is smart, and in a couple weeks with human direction and canine correction, no longer showed any interest in the chickens. Chasing off preditors is much more exciting. I go to work and all 3 are loose in the yard all day with my flock of free range chickens and guineas.
My trail cameras prove to me that the dogs work all day, chasing off critters.
This is Mo, best dog ever!