Dogs can be a wonderful addition to any family, but, as many people have found, training them to behave properly can be incredibly challenging at times. Whether it's trying to keep them off the couch, or they regularly make a 'mess' in the family living room, it can be tempting for many pet owners to just yell at their dogs when they screwed up in an attempt to correct that behavior.
However, a new study says all that yelling at your dog and other types of "aversive" training can have "long-term negative effects on your dog's mental state" according to a new study published by the biology news service, bioRxiv.
"Our results show that companion dogs trained using aversive-based methods experienced poorer welfare as compared to companion dogs trained using reward-based methods, at both the short- and the long-term level," the researchers wrote in the paper.
"Specifically, dogs attending schools using aversive-based methods displayed more stress-related behaviors and body postures during training, higher elevations in cortisol levels after training, and were more ‘pessimistic’ in a cognitive bias task than dogs attending schools using reward-based methods," researchers wrote.
Researchers led by biologist Ana Catarina Vieira de Castro at the Universidade do Porto in Portugal, recruited 92 pet dogs that included 42 pups who came from reward-based dog training schools, and 50 from an aversive-style, negative reinforcement, training school. The dogs were observed in two phases, a short-term and long-term assessment. For the short-term, recordings of the dogs were taken during three of their training sessions, with six saliva samples (three while being trained and three while at home with their owner) to measure their cortisol levels, the body's main stress hormone.
Researchers used the footage of the training sessions to look for stress-related behaviors, such as lip-licking and yawning, and each dog's overall mood. They found the dogs who went through aversive training had higher cortisol levels, even while at home, as compared to dogs who went through reward-based training.
About a month after the short-term assessment, researchers trained 72 dogs to associate a particular bowl with treats and empty bowls that smelled like sausage. The point was to determine whether the pups would be able to learn where to find the treats.
Dogs who underwent the reward-based training were faster in figuring out which bowls contained the snack, while their aversive-trained counterparts were not as eager to explore the room to find the snack.
"We found that the higher the frequency of aversive stimuli used in training, the greater the impact on the short-and the long-term welfare of dogs," researchers wrote. That means, the more often you try to discourage bad behavior in your pup, the worse off your dog will be in the long-term.
“Our study points to the fact that the welfare of companion dogs trained with aversive-based methods appears to be at risk,” the study’s researchers wrote in their paper on the assessments.