These two big boys recently graduated from the guardian dog training program at Werribee Open Range Zoo in Australia. They will be protecting livestock as well as endangered Eastern Barred Bandicoots. :
Maremma Sheepdog
Protector Pooch a Wild Idea at Werribee Zoo
Maremma Sheepdog Dog Breed Pictures, 1
Livestock guardian dogs are making a comeback to protect predators | New Scientist