Tosa Inus are one of the most fascinating, and misunderstood of all dog breeds and make great guard dogs. Tosa Inu’s origins began on the smallest Japanese island Shikoku. They were raised in the old Tosa province of the island, hence their name, and the Tosa province was one of the most popular areas for dog fighting.

Known as the Japanese Mastiff, the origins of the Tosa started with the Japanese being impressed with the large Western Bull Mastiff and decided to breed it with Bulldogs, Great Danes, and St. Bernards to improve the size and strength of the native Shikoku ken.

Tosa Inus are one of the few dogs that are still used legally for dog fighting, but these matches are not held with the same notoriety of the illegal fights known all over the world. Dogfights with Tosa Inus are handled under strict rules and never end with the death of either participant.

Tosas are stately, massive dogs who are athletic and surprisingly agile. Their head is large with a broad skull and a moderately long, squared-off muzzle. The jaws are very powerful, the skin at the neck forms a dewlap, the ears are fairly small and pendant, falling along the cheeks and the eyes are small, dark and almond-shaped, with a dignified expression. The long tail is very thick at the root then tapers to a point, reaching the hocks and the short-haired coat is dense and harsh. The preferred color is solid red, though black, yellow, fawn, brindle and multi-colored is also permissible.

The height of the Tosa averages around 24 inches with a weight ranging between 80 and 200 pounds and lives about 12 years.

As for use as a guard dog, the temperament of a Tosa is that of a very brave fearless dog attuned to his master’s wishes. They are protective and loyal. The Tosa can be exceptionally quiet and were bred to be a quiet dog because of Japanese fighting rules. The Tosa can be affectionate toward family members, reserved with strangers, but will accept someone new if introduced. However, due to their size, they should not be left around children.

If you choose to own a Tosa as a guard dog, a large fenced yard is sufficient for its exercise demands. But, they like to go for walks or jogs to satisfy its own need to walk. You might get behavioral problems if Tosas are not taken on daily walks.

Finally, keep Tosas away from other dogs that like to fight because this dog will win. They have a high tolerance for pain due to its fighting origins. So if you decide to own a Tosa as a guard dog, let it know its place, keep it away from other aggressive dogs, or you might end up with a dangerous weapon that will not be easy to take down.