Scientists and medical researchers experiment on dogs in laboratories. Although the evidence is limited, some studies suggests that the lack of enrichment and isolation from humans and other dogs is a serious welfare issue. In particular, these conditions may cause dogs stress, which is the physical and physiological changes that occur when an animal faces a difficult situation. 

This study compared the stress levels of beagles who lived in conventional lab settings with those living in more species-suitable conditions. Researchers separated eight beagles into two groups of four. One group lived individually in small, stainless steel cages with less than 20 square feet of space. The other group lived together in a much larger cage with nearly four times the space, which had a soft floor and four food toys to play with — one for each dog. The study lasted six weeks in total. 

The researchers used four methods of measuring the dogs’ stress: physical activity, stress hormone levels in the blood, food consumption, and body weight. Physical activity was measured using a collar that tracked the number of steps per hour. Stress hormone levels were measured by taking blood samples. Weight was measured using a “body condition score,” a measurement similar to the body-mass index (BMI) in humans.

They found that the dogs in the larger, more comfortable cage were more active and less stressed. One experimental dog fought with other dogs, so he lived alone in a cage with toys after the third week. When the dog that fought was excluded from analysis, experimental dogs took more steps per hour than control dogs throughout the study.

What’s more, the body condition scores and amount of food consumed were not significantly different between groups. However, minimal and excess food consumption can both be signs of stress, so these measures don’t necessarily tell us much.

Readers should be careful when extrapolating the results of this study. The sample size was small, and the dogs all lived in a comfortable environment with adequate water and food as well as vaccinations against common illnesses. As a result, the findings may not generalize to dogs in more stressful environments. Additionally, the dogs were likely stressed further when blood samples were taken. Less invasive methods of measuring stress hormone levels would give clearer data.

The results of this study may initially seem obvious; those familiar with caring for animals already know the importance of companionship and play. For dogs housed in labs, providing them with a more desirable environment should be an easy fix. As the authors point out, providing companionship, toys, and more comfortable floors are relatively straightforward and affordable changes. For animal advocates, calling for these higher welfare standards is one way to support laboratory dogs as we fight to end the use of animals in scientific research.