A watchdog is specially trained to detect any threats and identify all kinds of intruders into their territory. These type of dogs usually confront the threatening intruder but did not bite them. The dogs do not attack, and will alert you by loud barking. Many different breeds will be able to perform this role satisfactorily quite well. These are the type of watchdogs that would be the stranger to a wall and alert the owner by loud barking. If you want just a watchdog which will not attack anyone, pick a big and scary one. When the dog is big, the intruders will also get intimidated.
However, if intimidation is the only thing that you are aiming at, even the tiny Chihuahuas can be trained to do that. Large Mastiff is also used especially for this purpose. But miniature breeds like the Chihuahua have excellent hearing, and can make good watchdogs. They will be able to alert you whenever something goes wrong.
A personal protection dog is something that has been trained specifically to protect the owner and their family members from intruders and criminals. There are only some breeds that are suitable for being personal protection dogs. They are trained to work with commands and also to perform complex tasks. They will be obedient, and also, confront and track criminals. The personal protection dogs will also be able to attack the criminals if it is required. These type of breeds have the ability to bond with the owner very carefully. They are also very personable, alert, and bold. These dogs are very courageous and usually possess a highly athletic body.
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