The horses at the Children's Zoo in Gothenburg don't mind being pet by children and adults. However, they do get stressed by the noise from an excavator. Researchers at the University of Gothenburg have discovered this after fitting heart rate monitors to eight Gotland russ horses.
People and organisations that keep animals must take the animals' welfare into account. For zoos that work to conserve species and breeds and wish to promote biodiversity, it is crucial to understand how visitors affect the animals in the zoo.
"Although a great deal can be gleaned from the animals' behaviour, there is still some uncertainty about how they feel in the company of humans. That is why I have chosen to use heart rate monitors to find out how the horses in an animal park in Gothenburg are coping amidst all the people and activity. They actually don't seem to mind all that much," says Isidora Dundjerovic, lead author of the study.
Heart rate linked to stress
The heart rate is linked to stress. When stress strikes, the heart rate rises; this applies to animals just as it does to humans. The researchers measured the heart rates of eight horses, both whilst they were resting and whilst they were working - that is, walking for hours in the park. This provided good baseline data for comparison when the researchers subsequently measured their reaction to being surrounded by a group of children petting them whilst the horses were being fed hay.
"The resting heart rate averaged 42.5 beats per minute and 85 beats per minute during exercise. When the horses were in a paddock by a playground and were being pet by the children, their heart rate averaged 51 beats per minute. At one point, an excavator started up next to the paddock and the horses' heart rates shot up significantly and they quickly moved away from the machine," says Isidora Dundjerovic.
Barking dogs
The study clearly shows that a noisy machine was stressful, but the horses took other unexpected sounds and events in their stride. During their walks in the park, they encountered barking dogs on several occasions, and this had no effect on their heart rate; nor did passing cars.
"Horses, as animals, have been accustomed to coexisting with the people who care for them for thousands of years. We now know a little more about how they are affected by being in an environment with lots of people, which is important for ensuring their welfare," says Isidora Dundjerovic.
Pony riding
The research yielded reassuring results for those involved in animal husbandry at the animal park in Gothenburg, and they are looking forward to the publication of forthcoming studies, as pony riding, among other things, has been examined in a similar way.
"Animal welfare is extremely important, and we monitor the health and wellbeing of our animals in many different ways. We are delighted to be collaborating with the University of Gothenburg on in-depth analyses of animal welfare in this way, to ensure that we do not overlook any hidden stress among the zoo's animals," says Linda Thelin, zoologist at the animal park.
Scientific article in Zoo Biology: Heart Rate as an Indicator of Stress in Gotland's Russ Horses
