Dogs housed with a companion are less stressed and adopted faster than dogs housed alone, research finds

Shelter dogs awaiting adoption fare better with a canine companion than when they're housed alone, according to new research from Virginia Tech.

The study, led by Erica Feuerbacher, associate professor in the College of Agriculture and Life Sciences' School of Animal Sciences, revealed that companiable dogs housed together showed fewer signs of stress and were adopted more quickly than dogs that were housed by themselves.

Nearly 4 million dogs enter shelters every year, according to the American Society for the Prevention of Cruelty to Animals. The study's findings offer one possible solution for animal shelters struggling with limited space and long waits for dogs needing adoption.

"Despite being a social species, dogs are often housed alone in shelters to reduce disease transmission and possible injury from inter-dog conflict. But this social isolation can work against dogs' behavioral health and adoptability," Feuerbacher said. "We wanted to examine whether pair housing could be a useful intervention for improving shelter dogs' welfare."

Published in the journal PLOS ONE, the study is the first to examine how U.S.-based shelter dogs fare in co-housing versus solitary housing.

Previous studies of the benefits of co-housing dogs focused on laboratory beagles and veterinary school dogs who were housed long-term—or for more than six months—in kennels for teaching and research purposes. In contrast, shelter dogs spend an average of 35 days waiting to be adopted and are frequently accustomed to social interaction prior to their entry.

The study followed 61 dogs over seven days at the Humane Society of Western Montana. Researchers placed half the dogs in co-housing with partners who were matched through a brief introduction and compatibility test. The other half were kenneled alone.

Researchers observed the dogs throughout the week, recording common stress behaviors, including lip-licking, whining, and pulling back their ears, and took daily samples of the dogs' urinary cortisol and creatinine to measure biological indicators of stress.

"Dogs housed in shelters can face chronic levels of stress due to noise, confined kennel spaces, and limited access to social interaction," Feuerbacher said. "This can reduce their overall well-being, which might impact their adoptability."

Dogs housed together not only showed fewer stress behaviors, but they also were adopted, on average, four days sooner than single-housed dogs.

Feuerbacher hopes that the study's results will encourage animal shelters to match dogs with suitable "roommates" as a way to alleviate dogs' stress and show them at their best to potential adopters.

"Many potential adopters might already have a dog or would like to engage in social activities with their dog," Feuerbacher said. "Clearly exhibiting that a dog can successfully interact with other dogs might highlight those dogs as good matches—leading to more successful adoptions."

The research team included Grace Hecker, a current veterinary student at the Royal Veterinary College in London; Katherine Martineau, a former student research assistant at Carroll College who now works at Lewis and Clark Humane Society in Helena, Montana; Mariah Scheskie, a professional dog trainer and former director of programs, behavior, and training, at the Humane Society of Western Montana; and Rhonda Hammerslough, a professional dog trainer and Humane Society of Western Montana volunteer.

Feuerbacher's research, outreach, and teaching focus on companion animal behavior and welfare. Her recent efforts have centered on shelter dog welfare and interventions that can improve dogs' well-being and increase adoptions.

She also studies human-animal interactions, including dogs' preferences for different social interactions and how to use positive reinforcement training most effectively in training dogs.