These Polish guard dogs where extremely aggressive.
From what I know about farm and guard dogs, the guard dog is supposedly a full-time member of the flock, unlike the herding dog. The behaviour characteristics of the guarding dogs differ radically from those of the herding dogs, the result of centuries of breeding for selective traits that make for a successful guard dog. The physical characteristics and behaviour of herding dogs differ from those of guarding dogs. The primary goal when raising a guard dog is to ensure complete socialisation and bonding with the animals that will, in the near future, be in its care, however I’m not sure this is true of the above dogs.