Guard dog

A guard dog or watch dog (not to be confused with the attack dog) is a dog used to guard against, and watch for unwanted or unexpected people or animals. The dog is discriminating so that it does not annoy or attack familiar people.

Both guard dogs and watchdogs bark loudly to alert their owners of an intruder's presence and to scare away the intruder. The watch dog's function ends here; a guard dog is capable of attacking, or restraining the intruder. are often large enough, 100-200 lbs and strong enough to attack and drive away livestock predators such as wolves. Some smaller breeds (such as Keeshond and Tibetan Terrier) are excellent watchdogs but not guard dogs because they bark loudly to alert their masters of intruders but are physically small and not given to assertive behavior. Guardian breeds will bark to alert their master and to warn off an approaching animal, or human threat, prior to their interception of the trespasser. They are different from the smaller watchdogs in that they do not continue barking, they take action. The human shepherd would in many cases come to the guard dog's aid with a weapon, not letting the dog fend for itself.

The following breeds are the best at watch dog barking:

If the risk is from human intruders, a suitable dog can be simply trained to be aggressive towards unrecognized humans and then tethered or enclosed unsupervised in an area the owner wishes to protect when he is not around (such as at night); the stereotypical "junkyard dog" is a common example of this. If the purpose of the dog is to protect against human intruders after nightfall, a large, dark colored dog in a dark house (lights off) would give the dog an advantage over the burglar. Other guard dogs intended for police or more supervised work are trained to bite, restrain and release an intruder only on the specific commands of its handler—as in Schutzhund or K9 Pro Sports training.

While the Airedale terrier, historically, was a British police dog, nowadays, breeds include the Doberman, the Rottweiler and the German Shepherd. Many currently prominent guard dogs started as general purpose farm dogs, but gradually developed into guard breeds. The Rhodesian Ridgeback is a determined defender of the home and can be very hostile to an enemy of its family. Some breeds, such as the American Pit Bull Terrier, were originally bred for fighting.

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