A dog that has been mistreated may be sad, depressed, or compulsively repeat certain behaviors, such as barking at all hours. Abuse, physical or psychological, leaves sequelae in the dog that has suffered it. The behavior of an animal that has suffered abuse by its owner changes, especially if it lasts for months or years. A distrustful dog, with problems relating to other animals or people in its environment, and even certain types of aggression, may indicate that the dog has been mistrea...