Characterization of stress coping style in Senegalese sole ( Solea senegalensis ) juveniles and breeders for aquaculture

Abstract

The aim of this work was to characterize stress coping styles of Senegalese sole (Solea senegalensis) juveniles and breeders and to select an operational behavioural screening test (OBST) that can be used by the aquaculture industry to classify and select between behavioural phenotypes in order to improve production indicators. A total of 61 juveniles and 59 breeders were subjected to five individual behavioural tests and two grouping tests. At the end of the individual tests, all animals were blood sampled in order to measure cortisol, glucose and lactate. Three tests (restraining, new environment and confinement) characterized the stress coping style behaviour of Senegalese sole juveniles and breeders and demonstrated inter-individual consistency. Further, the tests when incorporated into a principal components analysis (PCA) (i) identified two principal axes of personality traits: ‘fearfulness-reactivity’ and ‘activity-exploration’, (ii) were representative of the physiological axis of stress coping style, and (iii) were validated by established group tests. This study proposed for the first time three individual coping style tests that reliably represented proactive and reactive personalities of Senegalese sole juveniles and breeders. In addition, the three proposed tests met some basic operational criteria (rapid testing, no special equipment and easy to apply and interpret) that could prove attractive for fish farmers to identify fish with a specific behaviour that gives advantages in the culture system and that could be used to establish selection-based breeding programmes to improve domestication and production.

Reproductive success of a marine teleost was correlated with proactive and reactive stress‐coping styles

“…Captive S. aurata breeders presented two main consistent behaviours in response to the different coping style tests performed. The individual tests identified fish with different activity levels and distinct physiological changes that represented behavioural styles ranging from proactive and reactive traits (Castanheira et al ., ; Ibarra‐Zatarain et al ., ; Koolhaas et al ., ; Øverli et al ., ). Similarly, the risk‐taking test determined individual behavioural differences between coping styles of fish that crossed, defined as proactive and those that did not cross categorised as reactive (Harris et al ., ; Réale et al ., ).…”

“…The first test, restraining test, consisted of netting fish individually in the water and three behavioural variables were evaluated for 120 s: (a) the first activity time (s), or latency time to move, of the fish once in the net (NetFirstAct); (b) the total activity time (s) of the fish spent moving or trying to escape from the net (NetTotAct); and (c) the total number of escape attempts (NetEsc) ( Solea senegalensis Kaup 1858 (Martins et al ., ); S. aurata (Castanheira et al ., ); Gasterosteus aculeatus L. 1758 (King et al ., ); S. senegalensis (Ibarra‐Zatarain et al ., ). The second test, confinement test, consisted of evaluating for 300 s the reaction of fish to confinement (the fish was placed in a small tank (56 cm length × 36 cm width × 30 cm depth) with a constant flow through of oxygenated water) by evaluating two variables: the latency to the first activity time (s) of fish in confinement (ConLat) and the total activity time (s) in confinement (ConAct) ( Lepomis macrochirus Rafinesque 1819 (Wilson & Godin, ); Cyprinus carpio L. 1758 (Huntingford et al ., ); G. aculeatus (King et al ., ); S. aurata (Herrera et al ., ); Dicentrarchus labrax (L. 1758) (Ferrari et al ., ); S. senegalensis (Ibarra‐Zatarain et al ., ). The third trial, anaesthesia test, consisted of evaluating the time required (s) to induce 5 different anaesthesia levels (Table ) ( Ictalurus punctatus (Rafinesque 1818) (Welker et al ., ); Danio rerio (Hamilton 1822) (Nordgreen et al ., ).…”

“…To reduce the possibility of interference of transient motivational states with individual behavioural responses, fish were fed ad libitum in the evening before testing, therefore, all individuals were, presumably, equally motivated for feeding. This test, which has been widely used to discriminate personalities and definitions of behaviours, were adapted from other studies performed with S. aurata (Castanheira et al ., ) and other fish species such as, L. macrochirus (Wilson & Godin, ), mulloway Argyrosomus japonicus (Temminck & Schlegel 1843) (Raoult et al ., ), Dicentrarchus labrax (Ferrari et al ., ) and Solea senegalensis (Ibarra‐Zatarain et al ., ).…”

“…To avoid blood coagulation and protein degradation, a solution of 10 μl sodium heparin (5%, 25.000 UI; HOSPIRA; http://www.hospira.co.uk) and 15 μl aprotinin (from bovine lung; 0.9% NaCl, 0.9% benzyl alcohol and 1.7 mg of protein; Sigma‐Aldrich; http://www.sigmaaldrich.com) was placed inside Eppendorf tubes, while the syringes and needles were coated with heparin. Blood samples were centrifuged at 3000 g and 4°C for 15 min (ThermoScientific centrifuge, M23i; Thermo rotor AM 2.18; 24 × 1.5 ml; http://www.thermoscientific.com) and the plasma supernatant was removed and stored in triplicate at −80°C prior to analysis (Ibarra‐Zatarain et al ., ; Martins et al ., ). Cortisol was measured by a competitive conjugated binding ligand by means of a commercial ELISA kit (range of detection: 0–800 ng ml −1 ; Demeditec; http://www.demeditec.com), whereas glucose and lactate were measured by means of commercial enzymatic colorimetric kits (Spinreact SAU; http://www.spinereact.com).…”

Stress responses of juvenile brown trout under winter conditions in a laboratory stream

“…Before analysis, cortisol from 20 ll plasma was extracted with 1 ml ethyl acetate and evaporated to dryness. Plasma cortisol concentrations were determined using a competitive conjugated binding ligand by means of an ELISA kit (DE1887; range of detection: 0-800 ng ml; Demeditec Diagnostics GmbH, KielWellsee, Germany) (Velasco-Santamaría & CruzCasallas, 2007;Ibarra-Zatarain et al, 2016;PinedoGil et al, 2016). The ELISA was carried out in accordance to the manufacturer's protocol.…”