FN Archimer Export Format PT J TI Measuring cortisol in fish scales to study stress in wild tropical tuna BT AF ROQUE D'ORBCASTEL, Emmanuelle Bettarel, Yvan Dellinger, Marion Sadoul, Bastien Bouvier, Thierry Monin Amandé, Justin DAGORN, Laurent Geffroy, Benjamin AS 1:1;2:1;3:1,2;4:1,3;5:1;6:4,5;7:6;8:1; FF 1:PDG-ODE-LITTORAL-LERLR;2:;3:;4:PDG-RBE-MARBEC-LAAAS;5:;6:;7:;8:PDG-RBE-MARBEC-LAAAS; C1 MARBEC Univ Montpellier, CNRS, Ifremer, IRD, Sète, France Department of Aquaculture and Fish Biology, Hólar University, Hólar, Iceland ESE, Ecology and Ecosystem Health, Inrae, Institut Agro, Rennes, Brittany, France Centre de Recherches Océanologiques (CRO), DRAV, 29, Rue des pêcheurs, BP V 18, Abidjan, Côte d’Ivoire Cocody 2 Plateaux Aghien, 01 BP 3012 Abidjan 01, Abidjan, Côte d’Ivoire MARBEC Univ Montpellier, CNRS, Ifremer, IRD, Sète, France C2 IFREMER, FRANCE UNIV HOLAR, ICELAND AGROCAMPUS OUEST, FRANCE CRO, COTE IVOIRE Cocody 2 Plateaux Aghien, 01 BP 3012 Abidjan 01, Abidjan, Côte d’Ivoire IRD, FRANCE SI SETE PALAVAS SE PDG-ODE-LITTORAL-LERLR PDG-RBE-MARBEC-LAAAS UM MARBEC IN WOS Ifremer UMR WOS Cotutelle UMR copubli-france copubli-p187 copubli-europe copubli-int-hors-europe copubli-sud IF 1.798 TC 7 UR https://archimer.ifremer.fr/doc/00703/81509/85941.pdf LA English DT Article DE ;Fish scales;Cortisol;Tress;Welfare;Kipjack tuna;Yellowfin tuna AB Cortisol is recognized as a physiological indicator of stress in fish. However, this hormone is typically measured in plasma samples. In this study, cortisol content was evaluated for the first time in the scales of tropical tuna. The sample included 20 skipjack tuna (Katsuwonus pelamis) and 25 yellowfin tuna (Thunnus albacares) collected in the Atlantic (the Gulf of Guinea off the Ivory Coast) and the Indian Ocean (off Reunion Island), and their scales were analyzed using an ELISA test. The results indicated that on average, cortisol concentration (1) did not show any geographical pattern, (2) was independent of fish size, and (3) was significantly higher in skipjack (mean 4.75 ± 6.56 ng g−1) than in yellowfin (mean 1.65 ± 1.85 ng g−1), although the difference was mainly due to four skipjack individuals. Larger datasets would be needed to confirm any species difference in cortisol concentration. The particularly high cortisol concentration observed in four individuals may be due to fish from different schools, suggesting the need for future sampling from free-swimming schools to investigate intra- and inter-school variability in cortisol concentration. This study opens the door for future research, including the collection of scales on tagged individuals, to investigate the links between chronic stress and behavior in these species. PY 2021 PD JUL SO Environmental Biology Of Fishes SN 0378-1909 PU Springer Science and Business Media LLC VL 104 IS 6 UT 000667043200001 BP 725 EP 732 DI 10.1007/s10641-021-01107-6 ID 81509 ER EF