Dogs Enjoy Music, especially college soft rock

The effect of different genres of music on the stress levels of kenneled dogs- Bowman et al. 2017

• Abstract: dogs were played 5 types of songs for 5 days of enrichment, found there to be no significant difference in barking, but significantly more barking after auditory enrichment has ended, and significantly more heart rate variability when listening to soft rock and reggae (sign of decreased stress). However urinary cortisol levels were significantly higher during soft rock and the silent periods that followed auditory enrichment.
• Introduction: Dogs in kennels are exposed to high amounts of stress that can come from lack of control, novelty, high level of noise, among others. Chronic stress at these levels can further perpetuate aberrant behaviours, affect their mental well-being and ultimately their ability to be re-homed. Enrichment in the form of classical music is positive for dogs but they habituate quickly to playlists, benefits seen on day 1 are gone by day 7. One way to observe this is to use Heart rate variability, the SNS is indicative of stress and has longer post-ganglionic neurones thus transmits impulses to the heart slower -> lower levels of HRV. By observing the variability of the heart they can tell if its SNS or PNS (the good one). This was found with classical music, intention of study is to see if different genres of music can be used to alter the experience.
• Methods: 38 dogs total, 24 males, 14 females, mix of neutered and not. Individual histories unknown given that it is a kennel and also had a mix of ages, but ages recorded, also mix of species. Groups were exposed to a type of song per day with a 6hr playlist, order of genre was mixed between groups, smart b/c habituation over time would be normal by doing this you can make sure the observations are because of the genre and not b/c of habituation to auditory enrichment. Observed HRV, urine samples, and behavioural measures.
• Results:
  – HRV was significantly different between silent periods and Soft rock, HRV significantly decreased. There was also a difference in ages and size. Motown showed a decreased respiratory rate which was significantly different from the increase seen in soft rock. Pop showed a decrease in pNN50 that was significantly different from the increase seen in Soft rock. Reggae showed similar levels to soft rock. Classical changes in two parameters were seen that were significantly smaller than soft rock.
  – Behaviours: dogs spent significantly more time lying down when listening to music, and spent significantly less time lying down after the music was shut off. Time of day also played a role in this, PM > AM. Dogs spent significantly less time standing during treatments. No effects on sitting. Dogs were also significantly more likely to bark following the cessation of auditory enrichment but this makes sense since they need to habituate to the lack of enrichment and since they have no control over the situation barking is a way of asserting some control.
• Conclusion: Increase in HRV and PNS dominance during auditory enrichment seems to show that dogs were less stressed at these times. They recommend altering the genre so as not to habituate the subjects and to fully reap the benefits of auditory enrichment.