How Well Do Rehomed Laboratory Dogs Adjust?

August 17, 2017
JoAnna Pendergrass, DVM

Dr. Pendergrass received her DVM degree from the Virginia-Maryland College of Veterinary Medicine. Following veterinary school, she completed a postdoctoral fellowship at Emory Universitys Yerkes National Primate Research Center. Dr. Pendergrass is the founder and owner ofJPen Communications, a medical communications company.

Many dogs used for laboratory research are euthanized when they are no longer needed; others are rehomed into private households. But how well do they adapt to their new homes?

A team of German researchers determined that rehomed Laboratory Beagles adjust well to their new living situations. According to the researchers, the study’s findings, which were recently published in PloS One, “demonstrate a high adaptive capacity of the rehomed laboratory dogs.”

The fate of post-experimental laboratory dogs has increasingly captured the public’s interest, placing emphasis on the dogs’ welfare. Importantly, rehoming these dogs into private homes circumvents euthanasia due to surplus or lack of further research need. Rehoming also has moral implications. “From a moral standpoint,” the researchers wrote, “humans have an ethical obligation to provide healthy animals with appropriate living conditions.”

Although rehoming is a major life change for laboratory dogs, it has been performed successfully in Germany for many years through either direct transfer to private homes or placement by animal welfare organizations specialized in rehoming.


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To date, studies on rehoming of laboratory dogs have been primarily experiential. The current study addressed the need for more rigorous scientific study of rehoming, which was mentioned during a meeting of the Laboratory Animal Science Association in 2000.

Data Collection

The research team evaluated 145 laboratory Beagles given to a rescue group (n=72) or animal shelter (n=73) by a pharmaceutical company, then rehomed. Data collection occurred through 3 modalities at designated time points:

  • Standardized behavior test: Conducted at the pharmaceutical research facility and 6 weeks after rehoming
  • Observational behavior test: Conducted 6 weeks post-rehoming to observe dog behavior in everyday situations
  • Phone interviews: Conducted 1 week (“Interview 1”) and 12 weeks (“Interview 2”) post-rehoming to ask about dog behavior in everyday situations

If owners reported a dog’s panicking with certain behaviors, or if a dog panicked during previous standardized testing, those panic-inducing behaviors were excluded from that dog’s observational testing.

Observational test behaviors were scored from 0 (friendly) to 3 (fearful or undesired). Dogs also received body language and personality scores.

Statistical analysis was performed to identify correlations among study results and determine scoring influences.


Phone Interviews

Positive behaviors, including enjoyment during petting, were reported frequently in both interviews. Although negative behaviors were reported less frequently, the researchers observed increases in certain negative behaviors, particularly defensive aggression toward unknown children (0% in Interview 1; 13% in Interview 2).

Observational Test

Observed behaviors were primarily friendly and relaxed. Fear toward unknown objects, such as vacuum cleaners and garbage cans, was also observed. Fear, the researchers noted, is common in rehomed dogs; educating new owners can help prevent and manage this fear.


Observation test scores correlated well with the standardized test and phone interview findings, indicating the usefulness of observing rehomed laboratory dogs in everyday situations. Importantly, an owner’s willingness to adopt another laboratory dog poorly correlated with behavior problems, indicating a high level of owner patience and understanding.

Scoring Influences

Several factors strongly influenced the dogs’ behavior and personality scores:

  • Behavior scores were higher for females versus males.
  • Personality scores were higher for females versus males, puppies versus adults, and dogs in families with children versus without children.

Future Recommendations

Given the rehomed laboratory Beagles’ high adaptive capacity in this study, the researchers proposed several recommendations for the rehoming process:

  • Laboratory Beagles can be rehomed as puppies or adults.
  • The rehoming organization should carefully select and educate new owners.
  • Although laboratory Beagles can be rehomed in families with children, new owners should enforce safety rules to prevent bites.

Dr. JoAnna Pendergrass received her Doctor of Veterinary Medicine degree from the Virginia-Maryland College of Veterinary Medicine. Following veterinary school, she completed a postdoctoral fellowship at Emory University’s Yerkes National Primate Research Center. Dr. Pendergrass is the founder and owner of JPen Communications, a medical communications company.