My name is Sofia, and I am doing my thesis research on respiration in dolphins. After working as a small animal veterinarian for some years, I wanted to immerse myself in ethology and decided to study the master’s programme Applied ethology and animal biology.
Spirometry is a non-invasive method used to assess pulmonary function concerning limitations in respiratory flow and volume, in both humans (e.g. asthma patients) and animals. The aim of the project is to evaluate the use of spirometry as a diagnostic tool for assessing pulmonary function in bottlenose dolphins under human care, in relation to seasonal coughing.
In veterinary medicine, spirometry has been used to some degree during anaesthesia in small animals, as well as in examinations of horses with face mask, but has otherwise been hindered by the challenge of inducing an animal to make maximal expiratory efforts on demand. Nevertheless, this manoeuvre could be achieved through applying a significant negative pressure at the airway opening, or a considerable positive pressure on the thoracic wall. The latter represents what occurs when dolphins are beached and the thorax becomes compressed due to the body weight. Spirometry measurements may thus be developed for the examination and triage of beached wild cetaceans. This may be of particular importance in mass strandings, where rapid health evaluations and prioritisation of the release of healthy individuals before they begin to suffer from stranding-associated medical issues is crucial.
The animal caretakers at Kolmården Wildlife Park have been recording the frequency of coughing in their dolphins since January 2018 and have reported an increase in coughing, particularly during late summer, with the highest frequency occuring in August. Other clinical symptoms or signs of inflammation have not been consistently reported during these annual coughing periods, and the coughing often subsides without treatment after approximately three weeks. Until now, the aetiology of these symptoms has not been investigated, in part as until now there has been no tool to assess functional changes associated with respiratory issues.
In this study, bottlenose dolphins at Kolmården Wildlife Park will undergo regular spirometry testing throughout the year (May 2024-May 2025). Prior to initiating pulmonary function testing, the animals have undergone training through operant conditioning to become habituated to the equipment, as well as to maintain a stationary position in the water along the poolside during the testing. Additionally, the dolphins are trained to breathe and perform maximal respiratory efforts ("chuffs") through a custom-built spirometer, which is temporarily placed over their blowhole. This testing will help assess whether respiratory flow and/or volume change during periods of coughing.