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.
American Staffordshire Terrier. American Staffordshire Terrier. Another type of pitbull, somewhat larger than the APT, is the American Staffordshire. This dog weighs 65 to 90 pounds and is built similarly, but has a thicker coat. The build is square and muscular, and like American Pitbull Terriers, Staffies have a friendly and loyal nature.