A breath test for dolphins

US engineers have developed a new device for collecting dolphin breath for analysis, which could make it easier to check the animals’ health. Professor Cristina Davis and colleagues from the University of California, Davis (UC Davis) developed and tested the device in collaboration with researchers at the National Marine Mammal Foundation and the Chicago Zoological Society’s Mote Marine Laboratory.

Writing in the journal Analytical Chemistry, the team explained that direct health assessment of wild marine mammals is inherently difficult. Invasive techniques such as skin biopsies and blood sampling are particularly difficult to perform on wild, free-ranging dolphins.

Professor Davis’s team had worked on techniques for analysing exhaled human breath, which contains compounds called metabolites that can hint at a person’s diet, activity level, environmental exposures or disease state. The researchers wanted to develop a way to capture dolphin breath so they could gather this kind of information on marine mammals, though they acknowledged breath analysis metabolomics is “analytically challenging”.

The researchers designed an insulated tube that traps breath exhaled from a dolphin’s blowhole and freezes it. They analysed samples to create profiles of the mix of metabolites in breath, established baseline profiles of healthy animals and were able to “study changes in metabolic content of dolphin breath with regard to a variety of factors”, the researchers said.

The researchers concluded that breath analysis could be used to diagnose and monitor problems in marine mammals - and, by extension, in ocean health; deepen our understanding of the mammals’ biology and physiology; and assist future wildlife conservation efforts.