A barking dog can often scare off thieves more often than a pricey alarm, but which breeds do the job? It may surprise you that even a smaller (but alert) dog can do the trick.

8. Giant Schnauzer Image: Konstantin Zamkov/Flickr A dominant and loyal breed, the Giant Schnauzer is a high-energy dog that craves companionship and is quick to defend its humans.

A giant schnauzer named Monty has won the top prize at the ... is a 158-pound (71.6 kilogram) Neapolitan mastiff. The jowly breed was developed to be an imposing guard dog, but Brina’s owner ...

A giant schnauzer named Monty has won the top prize at the ... is a 158-pound (71.6 kilogram) Neapolitan mastiff. The jowly breed was developed to be an imposing guard dog, but Brina’s owner ...

A giant schnauzer named Monty has won the top prize at the Westminster Kennel Club dog show. Monty bested six other finalists to take best in show at New York’s Madison Square Garden.

A giant schnauzer named Monty has won the top prize at the Westminster Kennel Club dog show. Monty bested six other finalists to take best in show at New York’s Madison Square Garden.

A giant schnauzer named Monty has won the top prize at the ... is a 158-pound (71.6 kilogram) Neapolitan mastiff. The jowly breed was developed to be an imposing guard dog, but Brina’s owner ...

A giant schnauzer named Monty has won the top prize at the ... is a 158-pound (71.6 kilogram) Neapolitan mastiff. The jowly breed was developed to be an imposing guard dog, but Brina’s owner ...

A giant schnauzer named Monty has won the top prize at the Westminster Kennel Club dog show. Monty bested six other finalists to take best in show at New York’s Madison Square Garden.