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Characteristics, History, and Health
Tosa Inu
The Tosa Inu, also known as Tosa Ken, Tosa Dog, or Japanese Mastiff, hails from Japan, where it was bred as a fighting dog. It originated in the second half of the 19th century in Tosa (present-day Kochi), which is how the breed got its name. The breed was created by crossing local Japanese dogs with several foreign breeds like the English Bulldog, Mastiff, Saint Bernard, and the German Pointer, to create a powerful and agile fighting dog. The resulting breed was not only a capable fighter but also highly intelligent and trainable.
Main Info
- Origin
- Japan
- Lineage
- Mastiff and Bull-Type Lineage
- Alternate Names
- Tosa, Tosa Dog, Tosa-Ken, Tosa Tōken, Japanese Mastiff
- Life Expectancy
- 10-12 years
- Average Male Height
- Minimum 21.5-23.5 inches
- Average Female Height
- Minimum 21.5-23.5 inches
- Average Male Weight
- 100-200 pounds
- Average Female Weight
- 100-200 pounds
- Coat Length
- Short
- Coat Type
- Smooth, Double
- Coat Colors
- Red, Fawn, Black, Brindle
- Coat Pattern
- White Markings
Genetic Predispositions and Health
Like other large breeds, Tosa Inus can be predisposed to a few health conditions. Some of the common health issues seen in this breed include hip and elbow dysplasia, heart disease, allergies, and gastric torsion (also known as bloat).
Personality and Behavior
Tosa Inus are known for their quiet, patient, and calm temperament. They are brave and confident, with a natural protective instinct, making them excellent watchdogs. Despite their history as fighting dogs, they can be very gentle and affectionate towards their human families. However, due to their size and strength, they are not recommended for novice dog owners. Proper socialization and training from a young age is essential.
Mastiff and Bull-Type Lineage
A canine genetic lineage is a group of individuals or entire breeds that descended from common ancestors predating modern breed formation. Often these lineages are associated with a ‘type’ of dog with a unique historical working role and associated behaviors (e.g., herding, scent hunting, etc.).
Mastiff and bull-type breeds have strong, muscular builds. Both mastiff and bull-type breeds are protective and loyal, which are essential traits for this breed as guardian dogs and as companions. Although they appear imposing, many of these breeds are known for their gentleness and affection towards their families. They are a great example of loyal guardian dogs.
Example breeds with ancestry from this lineage include French Bulldog, St. Bernard, and Bullmastiff.
Fun Facts
In their native Japan, Tosa Inus are often referred to as the "Sumo wrestler of the dog world" because of their size and their history in dog fighting, which was conducted in a manner similar to sumo wrestling.
Despite their fearsome reputation and size, Tosa Inus are known to be 'silent' fighters, and they are often called the "Silent Tosa" as they do not typically bark or growl while fighting.
Tosa Inus are a rare breed, even in Japan, and owning one can be considered a status symbol.
References
https://vgl.ucdavis.edu/breed/tosa-inu?page=1
https://www.akc.org/dog-breeds/tosa/
https://www.ukcdogs.com/tosa-ken
https://www.fci.be/en/nomenclature/TOSA-260.html
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