Among the breeds many believe to possess this quality are Boxers, American Staffordshire Terriers, and Bulldogs, though there are many other breeds considered to be "Pit Bull types" that also are credited with being members of the "locking jaw" family.

Do dogs have lockjaw?

As mentioned, “lockjaw” is a casual term for a dog being infected and losing the ability to control his or her jaws. The tightening of the jaw muscles may in fact lock their mouths in place, in addition to other side effects, such as difficulty breathing or swallowing. Lockjaw is a real syndrome.

Do pitbull jaws lock?

Pit Bulls do not have locking jaws, in fact, no healthy dog does! There is a very serious Tetanus infection that can cause rigid jaw muscles and should receive immediate medical attention. What Pit Bulls do have is a very strong bite, roughly equivalent to a German Shepard's, and strong jaw muscles.