A new study offers rare comprehensive data on what owners can expect in the six months after adopting a dog from a shelter: These dogs may display a variety of problem behaviors that ebb and flow, but owners tend to be highly satisfied with the four-legged family addition despite the lengthy adjustment period.
Researchers surveyed new owners of dogs adopted from five Ohio shelters at four time points after the pet went home - seven, 30, 90 and 180 days later - using a research tool called the Canine Behavioral Assessment & Research Questionnaire (C-BARQ).
Results showed the dogs had a high prevalence for aggression toward strangers, their owners and other dogs that changed in a variety of ways over time, and separation-related behavior problems decreased at the six-month time point. By the study's end, 93.7% of owners rated their dog's overall behavior as excellent or good and 100% reported their pet had adjusted to the new home extremely or moderately well.
"We really got to see where in the timeline the pet's behavior may change or may not change, and that's really the key," said lead study author Kyle Bohland, assistant professor-clinical of behavioral medicine in the Department of Veterinary Clinical Sciences at The Ohio State University.
"The shelter system touches many lives, both humans and pets," said Bohland, whose practice centers on companion animal behavior. "And so it's important for us to be able to counsel owners on what may or may not change in the future so they can be better prepared to handle those consequences and then, hopefully, keep dogs in homes."
The study was published recently in the journal PLOS ONE.
Statistics show that about 2 million dogs are adopted from U.S. shelters every year.
An internet search about adopting shelter dogs will return results suggesting these pets' behavior will change three days, three weeks and three months after joining a household. Three days makes sense, Bohland said, because the stress hormone cortisol is known to spike in dogs when they enter a new environment, and then returns to normal in a few days.
"But the three-week and three-month rule really had no scientific basis," he said. Previous studies on adopted shelter dogs took a piecemeal approach, testing one point in time in the new home or using unvalidated surveys.
So Bohland and his colleagues set out to take a longer look at dog behavior changes in their forever homes using C-BARQ, which provides a standardized way to assess an individual dog's behavior. They recruited participants who adopted dogs from four shelters in the Columbus area and one in Cleveland.
Ninety-nine new adopters completed the first survey a week after taking their dogs home, and repeat surveys were emailed to those participants one, three and six months after the adoption. Sixty-two owners answered all four surveys.
The survey contained 42 questions asking participants to use a 0-4 scale to rate excitability; aggression directed toward strangers, owners and either familiar or unfamiliar dogs; fear; touch sensitivity; separation-related behavior; attachment and attention seeking; chasing; and energy level. Owners were also asked at each time point to rate their overall satisfaction with the dog's behavior and document any changes in their household.
Among behaviors that changed, results showed that a few increased at all time points: stranger-directed aggression, chasing behavior and training difficulty. Increases in excitability and touch sensitivity were reported at 90 and 180 days.
Two characteristics, separation-related behaviors and attachment and attention-seeking, decreased by the six-month mark.
Of behaviors that didn't change, a few still stood out for their high prevalence at various time points: dog-direction aggression (75%), familiar dog aggression (37.8%), and owner-directed aggression (32.3%).
"The biggest thing that stuck out to me was that we've got a lot of aggression among dogs in our community. That definitely concerns me from a public health standpoint and from a human mental health standpoint, because we've got a lot of dogs that are struggling - and that has human implications," Bohland said.
"And the other big piece was that despite that, people were pretty darn happy with their dogs," he said. "This combination of findings is a reminder that just about everybody has, on some level, dealt with unpredictable behavior problems, illnesses and the quirks of animal aging - and we still love our dogs. Overall, this really speaks to the bond people have with their pets."
Statistical analysis suggested that in some cases, a dog's size, age or sex was associated with specific behaviors. Dogs treated in the shelter with anti-anxiety medications were more apt to show aggression toward strangers and touch sensitivity after adoption - likely because those pets were more difficult to handle from the beginning, not because the medications made it worse. Researchers deliberately left breed out of the analysis - most dogs were described as mixed breeds, and all were neutered.
Based on what the researchers see in their practice, some behavior changes make sense: Stranger aggression may increase as dogs feel more protective of their new environment, and separation anxiety logically lowers as dogs settle into a household routine. Touch sensitivity might go unnoticed for months - until that first nail trim.
Seven adopted dogs were returned to the shelter during the study, resulting in a return rate of 7.1%. The national average return rate is about 15%.
"The bottom line is we don't want to see dogs coming back to shelters," Bohland said. "A lot of what we study comes from clients having questions. So my hope is that in the long term, this can help shelter employees and veterinarians target interventions that will help keep more dogs in their homes."
This work was funded by a grant from Ohio State's College of Veterinary Medicine. Co-authors were M. Leanne Lilly, Andréa Arruda and Jeanette O'Quin of Ohio State, and Meghan Herron of Gigi's Shelter for Dogs.
