RT Journal Article
T1 Rainbow trout welfare: comparing stunning methods in winter and summer
A1 González Garoz, Roberto
A1 Cabezas Albéniz, Almudena
A1 Fernández-Muela Garrote, Montserrat
A1 Martínez Villalba, Andrea
A1 González De Chávarri Echániz, Elisabeth
A1 Villarroel, Morris
A1 De la Llave-Propín, Álvaro
A1 Fuente Vázquez, Jesús De La
A1 Bermejo Poza, Rubén
A1 Díaz, María Teresa
AB This study investigates the effects of three stunning methods: thermal shock (TS), electric shock at 200 mA 2 s (ES2), and electric shock at 400 mA 0.5 s followed by 200 mA 1.5 s (ES4) - both electric shock treatments followed by thermal shock - on the stress response and energy metabolism of rainbow trout (Oncorhynchus mykiss) during winter and summer. A significant interaction between stunning method and season was observed for blood cortisol levels. In summer, cortisol concentrations were elevated regardless of the stunning method, whereas in winter, the ES4 method resulted in the lowest cortisol levels. Seasonal variation significantly influenced stress response in trout, with summer conditions leading to higher cortisol levels, darker skin pigmentation, and reduced liver glycogen and lipid reserves. Increased metabolic activity during summer was associated with enhanced reactive oxygen species (ROS) production, which triggered the upregulation of key antioxidant enzymes (sod, gpx, cat, gst). The results suggest that the choice of stunning method is critical in mitigating stress, with electrical stunning combined with thermal shock being more effective than thermal shock alone, particularly under elevated temperatures. These findings underscore the importance of optimizing stunning practices to improve fish welfare, especially in the context of climate change. Understanding the interplay between seasonal and procedural stressors provides valuable insights for improving aquaculture management and sustainability
PB Springer
SN 0920-1742
YR 2025
FD 2025
LK https://hdl.handle.net/20.500.14352/124475
UL https://hdl.handle.net/20.500.14352/124475
LA eng
NO González-Garoz, R., Cabezas, A., Fernández-Muela, M., Martínez Villalba, A., González de Chávarri, E., Villarroel, M., De la Llave-Propín, Á., De la Fuente, J., Bermejo-Poza, R., & Díaz, M. T. (2025). Rainbow trout welfare: comparing stunning methods in winter and summer. Fish physiology and biochemistry, 51(3), 110. https://doi.org/10.1007/s10695-025-01526-7
NO Author contributions: R.G.G.: Methodology, data curation, writing – original draft. A.C.: Methodology, writing – review & editing. M.F.M: Methodology, writing – review & editing. A.M.V.: Methodology, writing – review & editing. E.G.C.: Methodology, writing – review & editing. M.V.: Conceptualization, writing – review & editing. A.L.P: Methodology, writing – review & editing. J.F.: Conceptualization, writing – review & editing. R.B.P: Methodology, writing – review & editing. M.T.D: Conceptualization, validation, supervision, data curation, writing – review & editing
NO Ministerio de Agricultura, Pesca y Alimentación ( España)
DS Docta Complutense
RD 18 dic 2025