Where Ideas Grow

i3S award-winning work on animal welfare in research

PhD student Sara Jorge, carrying out research at i3S in collaboration with CIIMAR, won the Best Student Poster Award at the European Aquaculture Conference, which took place in Vienna, Austria. The work she presented proposes less aggressive and non-terminal alternatives for collecting cortisol (the stress hormone) in zebrafish, thus reducing the number of animals used in research.

For the student in the Doctoral Program in Veterinary Sciences, it is a great incentive to receive this distinction “at the main aquaculture event in Europe”, where scientists and industry come together to discuss the most recent discoveries and promote collaborations. “It reinforces my motivation to continue working tirelessly for a science that puts the well-being of fish at the center of its concerns”, highlights Sara Jorge.

“This recognition of the work I have been developing together with my supervisors demonstrates that we are on the right path to driving positive change in research and the aquaculture industry”, she adds. Sara Jorge is developing her research in the “Laboratory Animal Science” group, under the guidance of i3S researcher Ana Valentim, and co-supervision of Luís Félix, from UTAD, and Benjamín Costas, from CIIMAR.

Regarding the project she is developing, Sara Jorge clarifies that the “methodology currently used to extract cortisol from zebrafish is terminal or stressful”. As an alternative, she explains, “I am investigating the use of fish skin mucus, which acts as a natural barrier against pathogens and other sources of environmental stress”.

To evaluate the effectiveness of skin mucus as a biological material for measuring cortisol, the team carried out an experimental trial in which zebrafish were subjected to acute and chronic stress. The results, which were presented at this conference, “were promising, validating the use of mucus as a detector of acute stress, and opening horizons for its possible use as a detector of chronic stress”, guarantees Sara Jorge.

By developing less invasive and stressful methods, reinforces the PhD student, “not only does the welfare of zebrafish used in scientific research improve, but it also paves the way for more ethical and sustainable practices in the aquaculture industry”. Additionally, maintains Sara Jorge, “being a non-terminal method of collecting cortisol, we contribute to reducing the number of fish used in research and allow their reuse in longitudinal studies. Zebrafish in excellent welfare conditions will also be economically valued in the ornamental aquaculture market”.