The present study found no effect of audiobook exposure on the activity level of dogs in their kennels, nor on how they use the space inside the kennel. This is contrary to the findings of previous studies that found an effect of shorter-term audiobook exposure on behaviour of dogs in kennels.
Habituation could explain why the findings of this more long-term study contradict those of studies with shorter audiobook exposure periods. Dogs have been found to habituate to auditory enrichment very quickly, as early as the second day of exposure. As mentioned previously, for the present study 15-minute intervals were grouped and analysed by period (before, during, after) rather than by individual day. This meant that the data reflected behaviour during the period as a whole rather than behaviour on each individual day of the study. This method of data analysis may have masked any effect that audiobook exposure might have had on the dogs’ behaviour in the first days. Though it is impossible to conclude whether there was an effect on behaviour in the first few days that was simply not identified using this method, even if that were the case then these results do suggest that habituation happens within four days of prolonged exposure, which is important to know if the goal is to find the best way to implement this kind of enrichment effectively.
Novel Object Test “Jurassic Bark”
In terms of the novel object test the dogs overall did not show much interest in the object, so perhaps it was not sufficiently novel considering they are often given stuffed animals while in their kennels. Results of this test could also have been affected by the fact that the novel object was replaced between batches but not between dogs, so it is possible that the smell of previous dogs who had interacted with it could have affected the response of the next dog. The test was conducted outdoors so while all efforts were made to standardise it between dogs, there was a limit to how controlled the arena could be, and the test was not always executed uniformly. People passing by, noise levels and rainy weather during the tests of Batch 2 could all have had an impact on the reaction of the dogs.
Group and Batch Effects
It was found that the control group were consistently more active than the treatment group across all periods of the study. This result could suggest that there is some unidentified aspect of the control corridor which caused the dogs to be more active. Also, the dogs were split between the two corridors by the staff before the study began, so the extent to which this process was randomised is unknown. The control corridor was further from the main staff area than the treatment corridor was and seemed to receive less foot traffic which could have been a factor that was taken into account when choosing which dogs to place in each corridor.
The present study involved two separate batches of dogs which were studied at separate times, each having a control group and a treatment group. There was a difference in some aspects of behaviour between these batches both while inside their kennels, and when faced with the novel object when taken out for a walk. Batch 1 dogs showed a higher level of activity and spent less time in bed across all periods of the study, before treatment, during treatment and after treatment. In the novel object test, Batch 1 spent more time with their face orientated towards the object and spent more time sniffing the object than Batch 2 did. There are several possible reasons why this might have been the case. There could simply be a difference in the natural level of activity and curiosity amongst dogs and more active or curious dogs happened to be in the first batch. Alternatively uncontrollable environmental factors such as weather could have played a role in causing differences in activity level and time spent in bed, since there was an interval of 27 days between the trials of the two batches, and it was raining during the novel object test of Batch 2. There was also construction work going on in the building which could have resulted in different levels of disturbance to the two batches of dogs.
As this study was carried out in a busy dog shelter there were many aspects of the dogs’ kennel environment which it was not possible to control but which could potentially have impacted the results. There were kennels in each of the corridors that were occupied by dogs but not included in the study, the dogs in these other kennels could be moved or replaced by staff or new dogs could be introduced, potentially impacting the behaviour of the study dogs. While the staff did their best to only enter the corridors during the study when absolutely necessary, the outdoor area was not considered to be part of the study area. Anything that happened in the outdoor area was likely to affect the behaviour of the dogs, but this area was not monitored so it is impossible to know if there were any trends in staff activity in this area on any particular day of the study.
These uncontrolled factors could be considered as “limitations” if the aim is to explain why the results of this particular audio enrichment study differed from others which were carried out under different or more controlled conditions. However, these factors should certainly not be considered to have reduced the value and usefulness of these results. One of the main aims of this study was to investigate the potential of audiobooks as a tool in behaviour modification under real world conditions rather than in strictly controlled environments. Thus, the existence of factors that were out of the experimenter’s control in this case could be considered to be an advantage in seeking a more accurate picture of the effect of audiobook implementation in dog shelters. Most of these factors are aspects of the dog shelter environment that are unlikely to change, side-effects of the staff going about their daily essential tasks and some level of environmental unpredictability. They are things that dogs in shelters will experience when they are not taking part in such a study so these factors should not be eliminated while the dogs are being studied.
The main reason that the effects of audiobooks and other forms of audio enrichment on animal behaviour are being investigated is to determine their potential for use in reducing stress and modifying behaviour in real world scenarios. Studies conducted under highly controlled conditions may have limited relevance when it comes to real application of these audio enrichment methods where there are far more factors at play. This study represents a realistic scenario, unpredictable but more closely resembling that in which dogs will realistically find themselves while in shelters. When conducting studies of this kind, the aim being potential implementation of this method in real shelter environments, it is important to allow the shelter environment during the course of the study to reflect how it would be under normal conditions if realistic and useful results are to be acquired. Since any habituation effects that could have occurred within the four days of audiobook exposure would not have been detected by the chosen method of data analysis, habituation cannot be ruled out as the reason that these findings contradict those of similar studies. Future studies might further investigate this potential habituation effect and how audiobooks could be used in combination with other forms of auditory enrichment to best reduce stress and improve behaviour and thus adoptability.