American Staffordshire Terrier (Detailed Introduction)

　　The American Staffordshire Terrier, also known by many other names, is a medium-sized dog originating in the United States. Its appearance is very similar to that of the bulldog, so it is also called the fighting dog or bull terrier.
　　In fact, the American Staffordshire Terrier originated in Staffordshire, England, in the 19th century by breeding the English bulldog with certain English terriers. However, after being introduced to the United States, breeders improved the dog to increase its weight and give it a larger head, officially naming it the American Staffordshire Terrier on January 1, 1972.
　　Chinese scientific name: American Staffordshire Terrier
　　Chinese aliases: American Staffordshire Terrier, American Stafford Bull Terrier, American Staffordshire Bull Terrier, American Staffordshire Terrier
　English name: staffordshire bull terrier
　Kingdom: Animalia
　　Phylum: Chordata
　　Subphylum: Vertebrata
　　Class: Mammalia
　　Subclass: Theria
　Order: Carnivora
　　Suborder: Caniformia
　　Family: Canidae
　　Genus: Canis
　　Species: Domestic dog
　　Origin: United States.
　　Type: Medium-sized dog
　　Subspecies: American Staffordshire Terrier
　　Lifespan: 7-8 years
　　Distribution: As early as 1870, this dog appeared in the United States, where it was known by the names fighting dog and bull terrier. Later it was called the American pit bull terrier, and then became known as the Yak hard.