An animal's “behavior” is the product of its genetic composition, the environment in which the animal functions, and the animal's experience (ie, what it has learned given its previous genetic × environment interaction). This section focuses primarily on abnormal behavior of domestic animals and the methods used to diagnose behavior problems and modify behaviors in pets. For each group of domestic animals, the normal social and group behavior is outlined, followed by a description of common behavioral disorders.

Every animal has the basic needs of food and water, comfort, freedom from fear and pain, and the ability to express normal behaviors. Behavior, health, and welfare issues become a concern when these needs are not met. Behavior problems in pets lead to a weakened pet–owner bond and decreased owner commitment to pet care. They are a primary reason for pet relinquishment and euthanasia. Yet studies show that many owners do not report behavior changes to their veterinarian and most veterinarians neglect to inquire. Screening for any behavioral changes or emerging behavior problems should be done at each veterinary visit to ensure that the behavioral health, physical health, and welfare of the pet are being effectively and humanely managed.

Last full review/revision March 2012 by Gary Landsberg, BSc, DVM, MRCVS, DACVB, DECVBM-CA