Compulsive disorder in dogs

I have encountered a young dog in a neighbour's compound. It has this tendency to bite at my trouser and I decided to investigate the cause. This might be due to high stress levels or a consequence of frustration. Dogs with this disorder might adopt a certain repetitive behaviour like holding a toy or biting at clothes in order to relieve the stress. Dogs are likely to perform this behaviour again and again due to the reward associated with the action that causes a reduction of the physiologic feeling of stress or frustration. The impulse might become stronger and stronger with time. Dogs with a disorder of chasing their tails might end up injuring their tails. However, you have to distinguish whether its attention getting behaviour or OCD because there can be a thin line between the two. You should videotape your dog to see if it behaves similarly in your absence. Some dogs however are hereditarily predisposed to certain compulsive behaviours. Do you know of such breeds?

I sometimes observe that in our dogs particularly Pipoy, the hyperactive pug. But it is on rare occasions only. With biting the tail, most of our dogs did that when they were puppies but I never noticed that when they are already adults. Tisoy, our 8-year old spitz sometimes bites the hem of the pants when he wants to call our attention particularly when he wants to go out of the house. But definitely that's on purpose.