Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5925548 | Physiology & Behavior | 2012 | 7 Pages |
In this study we evaluated Pavlovian conditioned food anticipatory behaviour as a potential indicator for stress in groups of Atlantic salmon, and compared this with the physiological stress responses of cortisol excretion into water and hyper-consumption of oxygen. We hypothesised that environmental stress would result in reduced feeding motivation. To assess this, we measured the strength of anticipatory behaviour during a period of flashing light that signalled arrival of food. Further, we expected that fish given a reduced food ration would be less sensitive to environmental stress than fish fed full ration. The fish responded to an acute temperature fluctuation with hyper-consumption of oxygen that decreased in line with the temperature, and elevated cortisol excretion up to 1Â h after the stressor. These physiological responses did not differ significantly between the food ration groups. The anticipatory behaviour was significantly reduced after the stressor and returned to control levels after 1 to 2Â h in the reduced ration group, but not until after 3 to 4Â h in the full ration group. Our results show that acute stress can be measured in terms of changes to feeding motivation, and that it is a more sensitive indicator of stress that influences the fish over a longer time period than measures of change in cortisol excretion.
⺠We introduce conditioned anticipatory behaviour as a stress indicator in fish. ⺠This provides new insight into how fish experience their own situation. ⺠It has potential for fish research and as online welfare assessment in aquaculture.