FN Archimer Export Format PT J TI Cardiac and behavioural responses to hypoxia and warming in free-swimming gilthead seabream, Sparus aurata BT AF Mignucci, Alexandre Bourjea, Jerome Forget, Fabien Allal, Hossein Dutto, Gilbert Gasset, Eric McKenzie, David AS 1:1;2:1;3:5;4:2;5:3;6:3;7:4; FF 1:PDG-RBE-MARBEC-LHM;2:PDG-RBE-MARBEC-LHM;3:;4:;5:PDG-RBE-MARBEC-LSEA;6:PDG-RBE-MARBEC-LAAAS;7:; C1 MARBEC, Université de Montpelier, CNRS, IRD, Ifremer, 34200 Sète, France CHU de Montpellier, Service Chirurgie Pédiatrique, 34000 Montpellier, France MARBEC, Université de Montpellier, CNRS, IRD, Ifremer, 34250, Palavas-les-Flots, France MARBEC, Université de Montpellier, CNRS, IRD, Ifremer, 34095 Montpellier, France MARBEC, Université de Montpelier, CNRS, IRD, Ifremer, 34200 Sète, France C2 IFREMER, FRANCE CHU MONTPELLIER, FRANCE IFREMER, FRANCE CNRS, FRANCE IRD, FRANCE SI SETE PALAVAS SE PDG-RBE-MARBEC-LHM PDG-RBE-MARBEC-LSEA PDG-RBE-MARBEC-LAAAS UM MARBEC IN WOS Ifremer UMR WOS Cotutelle UMR copubli-france copubli-p187 IF 3.308 TC 5 UR https://archimer.ifremer.fr/doc/00710/82168/86964.pdf LA English DT Article DE ;Heart rate;Acceleration;Biologging;Respirometry;Star-Oddi;Confinement;Oxygen saturation;Teleost AB Gilthead seabream were equipped with intraperitoneal biologging tags to investigate cardiac responses to hypoxia and warming, comparing when fish were either swimming freely in a tank with conspecifics or confined to individual respirometers. After tag implantation under anaesthesia, heart rate (fH) required 60 h to recover to a stable value in a holding tank. Subsequently, when undisturbed under control conditions (normoxia, 21°C), mean fH was always significantly lower in the tank than in the respirometers. In progressive hypoxia (100% to 15% oxygen saturation), mean fH in the tank was significantly lower than in the respirometers at oxygen levels down to 40%, with significant bradycardia in both holding conditions below this level. Simultaneous logging of tri-axial body acceleration revealed that spontaneous activity, inferred as the variance of external acceleration (VARm), was low and invariant in hypoxia. Warming (21 to 31°C) caused progressive tachycardia with no differences in fH between holding conditions. Mean VARm was, however, significantly higher in the tank during warming, with a positive relationship between VARm and fH across all temperatures. Therefore, spontaneous activity contributed to raising fH of fish in the tank during warming. Mean fH in respirometers had a highly significant linear relationship with mean rates of oxygen uptake, considering data from hypoxia and warming together. The high fH of confined seabream indicates that respirometry techniques may bias estimates of metabolic traits in some fishes, and that biologging on free-swimming fish will provide more reliable insight into cardiac and behavioural responses to environmental stressors by fish in their natural environment. PY 2021 PD JUN SO Journal Of Experimental Biology SN 0022-0949 PU The Company of Biologists VL 224 IS 14 UT 000681398200011 DI 10.1242/jeb.242397 ID 82168 ER EF