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PORTO, Portugal - Training your dog with punishment tactics, such as yelling and leash jerks, can impact your pet’s stress levels in the long term, according to a recent study.
Researchers with the University of Porto in Portugal looked at how negative reinforcement versus reward-based training can affect a dog’s overall health.
The team recruited 92 dogs from three reward-based schools and four that used negative reinforcement or punishments. The dogs needed to have been at the school for less than two months and be free or any behavioral problems, such as aggression and fearfulness. The group of dogs was about 11 months old, on average.
First, the team looked at the short-term effects of the training sessions by procuring a total of six saliva samples from each dog. Three were taken when the dog did not have a training session and was relaxed at home, while the other three were taken after training sessions.
Each saliva sample was analyzed for cortisol levels, which is a stress hormone.
Dogs were also recorded to show any stressful behaviors, such as lip-licking, yawning or paw-raising.
Researchers found that dogs who were part of the punishment or negative-reinforcement training had higher cortisol levels and showed more stressful behaviors. The dogs who were part of reward-based schools showed less behaviors and had mostly normal cortisol levels, according to the results.
For long-term effects, the team had dogs participate in a spatial cognitive bias task. The task involved the dogs associating a bowl in a room with a snack.
Dogs were placed in a room in a research building at the university. According to the study, the dogs were trained to figure out the difference between a food bowl with a treat and an empty one. All of the bowls were rubbed with the treat so the dogs couldn’t use their sense of smell to figure it out.
Researchers moved the bowls around the room to see which dogs would continue to approach them for the treat. Dogs who were more actively engaged in the search were considered showing positive traits and dogs who appeared apprehensive and slow were deemed “pessimistic.”
In the end, study results indicated that punishment and negative-reinforcement training can result in higher stress levels for canine companions and that they exhibit more stress-related behaviors.
This story was reported from Los Angeles.