Among the strategies that can be used to improve fish welfare in a rearing environment,domestication and/or selective breeding was proposed to minimize fish responsiveness tohusbandry practices. To verify this hypothesis on a recently domesticated species, the seabass Dicentrarchus labrax, two experiments were realized, each using twopopulations differing according to their level of domestication or selection. For thefirst experiment, we used one population produced from wild parents (Wild;initial body mass: 106  ±  3 g), and one population from parents selected forgrowth for one generation (Selected 1; initial body mass: 129  ±  4 g).For the second experiment, we used one population produced from parents domesticated fortwo generations (Domesticated; initial body mass: 72  ±  3 g), and oneproduced from parents selected for growth for two generations (Selected 2;initial body mass: 89  ±  4 g). The first experiment was carried out over 112days with 240 fish (60 fish per tank, 120 fish per population), and the second one over 84days with 200 fish (50 fish per tank, 100 fish per population). Two variables,self-feeding behavior and growth performance, were measured over the time of theexperiments. After a control period, the fish were submitted twice, at three-weekintervals, to an acute stress treatment consisting of draining the tank and leaving thefish out of water for one minute. Both self-feeding behavior and growth performance werealtered by the acute stress treatment. During the first post-stress period, theDomesticated and Selected (1 and2) groups showed more pronounced post-stress exposure responses thanthe Wild fish: they modified their feeding rhythm, their feed intake, andtheir growth rate. During the second post-stress period, feeding rhythm was still affected(being more diurnal with a well defined peak), but the feed intake and growth rate resultsshowed that the Domesticated and Wild groups seemed lessaffected than the Selected (1 and 2)populations, which continued to express a high post-stress response.

According to these results, it can be concluded that: (1) an application of two acutestress treatments, at three-week intervals, modified fish feeding behavior and growthperformance; (2) the domestication process seemed to improve fish adaptation abilities tothis kind of stress; and (3) the process of selection for growth led to a final, bettergrowth, but did not seem to improve fish acute stress tolerance.