Dog behavior scientists suggest that in some situations dog owners contribute to their dogs' behavior problems, as is the case with separation-related disorder, also described as "separation anxiety" or "separation distress". Separation-related problems in dogs are a common behavioral complaint of owners. Approximately 14%-20% of dog patients from general veterinary practice show signs of this disorder. Recent studies show that this behavior develops because dogs with SRD do not use the owner as a secure base, in contrast with the popular theory which holds that SRD dogs are "hyper-attached" to the owner. SRD dogs do not show more affection toward the owner (expressed by e.g. proximity to and body contact with the owner, eye-contact with the owner, fast tail-wagging) which contradicts the "hyper-attachment" theory.
Dogs and humans have been living together for tens of thousands of years and during this time domestication might have predisposed dogs to form attachment relationships with humans. Dog puppies are typically acquired by human families at age between 6 and 10 weeks and the human owner becomes readily the primary attachment figure for the puppy, that is, they seek the proximity of the owner and show stress-response during separation from him. The proximity of the owner serves as a secure base for the dog for exploring the environment and a safe haven in threatening situations similarly as parents' proximity is for infants.
Dogs are social animals which have a strong inherent desire to interact with their social group including human family members. Humans also form an attachment relationship with their dogs. It was found that 93.3% of the owners consider their dogs as family members. Pet owners (mostly dogs and cats) see their pets mostly more like "own child" than any other family member. In addition, owners use their dogs as a safe haven (to alleviate stress) more than any other family members or friends, except for romantic partners.
In the owner's absence some dogs may develop separation-related disorder (SRD). Owners of dogs with SRD complain most frequently about destructive behavior displayed at home, excessive vocalization (often noticed by neighbors), or inappropriate elimination (urination/defecation, e.g.). Other symptoms include excessive salivation or heavy breathing, pacing, circling, over-grooming or self-mutilation, withdrawal, inactivity or loss of appetite, vomiting, diarrhea or escape behavior that can result in self-trauma. These dogs are very distressed upon separation and they cannot be easily calmed down by the return of the owner.
There is some evidence that dogs exposed to humans outside the home, and to a wide range of experiences between the age of 5–10 months are less likely to develop separation-related problems and that dogs that are separated from the litter early (less than 60 days) are more likely to develop problem behaviors, including destructive behavior and excessive vocalization, particularly if those dogs are sourced from pet stores. Confining a dog with separation anxiety to a crate can increase lip licking, a response consistent with stress, and dogs can injure themselves in attempts to escape from the crate.4 Dogs who meet refusal or ignorance of their needs such as need for contact can learn that they cannot be sure about the availability of the owner.
Dog owners who return to a house subjected to destruction may punish the dog. However, high frequencies of punishment are associated with anxious behavior for small dogs and dogs are less anxious when a high proportion of their training interactions involve positive reinforcement. Additionally, punishment delivered upon the owner's return to the house is likely to be ineffective. Thus, punishment is best avoided in dealing with dogs with separation-related problems.4 Recent studies show that after treatment with a behavior modification plan and fluoxetine dogs with SRP improved their behavior when alone.2
Separation anxiety is a disorder whose course may be difficult to alter in recently adopted shelter dogs. Having another dog in the home may not be protective against the development of separation anxiety. Brief counseling and a toy do not effectively prevent the occurrence of this complex behavioral condition.