It's not just serotonin either-most neurotransmitters can cause anxiety or anxiety like symptoms, and in some cases an over-abundance of a chemical can lead to anxiety. So it does appear that you can develop it without experiencing a stressful life.
Howard Heinzl (1918 - 1989) With regard to blue American Staffordshire Terriers, any breeder that believes that a blue American Staffordshire Terrier is some how more valuable than the other recognized colours, is not only deceiving themselves, but they are also deceiving their customers.
Summary: 1  The American Pitbull Terrier and the American Staffordshire Terrier both belong to the molesser breed group. 2  The Pitbull is taller, heavier and more muscular than the Amstaff. 3  Pitbulls are known to be passionate, aggressive, and physically powerful.  Some pitbulls today are used as police and therapy dogs.