Summary
Repetitive behaviors undertaken consistently tend to be labeled as compulsive. These behaviors may or may not be obviously detrimental to the affected animal's health. Licking certain areas of the body, as with the lower limbs in acral dermatitis, is a perfect example of this disease.
These behaviors, also referred to as "obsessive compulsive disorder" (or "OCD") may or may not be associated with stress or anxiety. Though it's been postulated that stress alleviation is the function of this disease, most veterinary behaviorists seem to agree that this disease is sometimes best defined by the fact that the repetition of the behavior itself serves no apparent function.
It's believed that this behavioral disorder has a genetic origin due to its increased prevalence in certain breeds. Both dogs and cats suffer from compulsive behaviors.
Symptoms and Identification
Any highly repetitive behavior undertaken with no apparent purpose, especially if it occurs in certain breeds, tends to be classified as a compulsive behavior. For dogs, characteristic compulsive behaviors dogs exhibit include the following: flank sucking, tail chasing, shadow chasing, fly snapping, generalized circling, fence running and repetitive pacing.
In cats, wool or fabric sucking (or eating) over-grooming or hair-pulling (psychogenic alopecia), and feline hyperesthesia (where cats become highly sensitized to certain stimuli) account for almost all compulsive behaviors.
Diagnosis is achieved via history and by observing the behavior. The difficulty (or complete inability) of a nearby observer to interrupt the behavior tends to lend weight to the diagnosis. Because diagnosis can be somewhat subjective for milder forms of the disorder, veterinary behaviorists are sometimes employed to help diagnose the condition as behavioral in origin.
Physical diseases must always be ruled out before arriving at a diagnosis for any behavioral condition. Other behavioral conditions like separation anxiety and cognitive dysfunction must also be fully explored as possibilities before defining the disorder.
Affected Breeds
Dobermans are predisposed to oral behaviors.
German Shepherds are drawn to tail-based compulsions.
Bull Terriers are recognized as more likely to exhibit spinning behaviors.
See acral dermatitis for a list of breeds predisposed to that particular compulsive behavior.
In cats, oriental breeds are overrepresented. Siamese cats, in particular, account for more than 50% of affected felines.
Treatment
The best treatment is often to seek the advice and guidance of an animal behaviorist. For dogs, the basic approach is as follows:
eliminate all stimuli that trigger the behavior
undertake basic training to help relieve stress
distract dogs from the repetitive behavior and redirect them to another
provide mental stimulation
provide systematic desensitization and counterconditioning
consider drug therapy
For cats, treatment is considered highly variable compared to that for dogs. Drug therapy is more typically elected as a matter of course, though all basic canine principles apply.
Veterinary Cost
Diagnosis of compulsive behaviors should ideally be confirmed by a veterinary behaviorist. This is always more expensive than when undertaken by a general practitioner. It's nonetheless considered a highly affordable alternative.
The cost of treatment depends on the severity of the condition and its consequences. For animals whose behavior yields severely destructive effects (such as self-mutilation and gastrointestinal obstructions), it's not unusual for medical and surgical costs to skyrocket into the thousands. More typically, however, pets who suffer this condition incur expenses associated with the behavioral aspects of their disease. Training, behavior modification and drug therapy can nonetheless reach into the low hundreds of dollars every month for some pets that require intensive therapy.
Prevention
Though inheritance modalities for most behavioral disorders have not yet been established it's considered advisable to refrain from breeding severely affected dogs and their first degree relatives (their parents and siblings).
References
Crowell-Davis SL 2008. Diagnosing and treating compulsive disorders. CVC Proceedings.
Crowell-Davis SL and Murray T 2006. Veterinary Psychopharmacology. Blackwell Publishing.