Pitbull breed

Pitbull is not a specific breed but a collection of different breeds that have certain physical characteristics however the true pitbull breed are those that are of the lineage of the English pitbull dogs that was taken into north America by the English immigrants. That purebred pitbull can be found in the American Staffordshire terrier (AmStaff) and the American pitbull terrier (APBT) which means that a true purebred blue nose pitbull has to be either APBT or AmStaff.

The pitbull is not a specific breed of dog but a name for a type of dog that share common physical and behavioral traits. The classes of dog breeds that constitute the pitbull are American pitbull terrier, American bulldog, Staffordshire bull terrier, American Staffordshire terrier and any other purebred (such as the famous pitbull blue nose) or breed crossed with any of these breeds.

Over 1,000 years ago in England, bull dogs were bred and used in the blood sport of bull baiting, a British pastime that involves tying a bull to the stake and setting these specially bred and trained bull dogs to attack them with the primary objective of seizing and holding the bulls by the nose as this was the most tender part of the bull. The bull dog breed was selectively bred into a powerful muscular breed with tremendous jaw power and the ability to bite and hold on with unyielding tenacity that even when it was violently tossed in the air by the bull it will not let go except its teeth got broken.

http://www.aboutdogfacts.com/blue-nose-pitbull/
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