Discipline : Éthologie

The closely associated concepts of welfare and stress may be considered as opposites since welfare cannot be achieved under stress and vice versa. Stress was first considered as an unspecific response to any challenge taxing the organism’s resources where the HPA axis plays a central role. Along the same lines, welfare was considered as the state of an individual on a continuum between poor and good depending on the efforts required to adapt to the environment. However, these views cannot explain opposite results such as up- vs. down-regulation of the HPA axis and hypo- vs. hyper-behavioural reactivity under chronic stress. … It is therefore suggested that the discrepancies found in the literature in terms of responses of the HPA axis or modification of behaviour under aversive conditions may stem from differences in the way a situation is evaluated. It is argued that stress comes from the animal’s evaluation of the outcome of a situation, and that welfare is the state resulting from that evaluation.