Entity

Time filter

Source Type


Benhaim D.,British Petroleum | Begout M.-L.,College de France | Lucas G.,British Petroleum | Chatain B.,Laboratoire Of Recherche Piscicole Of Mediterranee
PLoS ONE | Year: 2013

European sea bass aquaculture is so recent that very little is known on the effects of the early steps of its domestication. Behavioural parameters are sensitive indicators of the domestication process since they are generally impacted as soon as the first generation. The present work compared wild-caught and domesticated sea bass juvenile swimming activity, exploration and ability to learn to discriminate between two 2-D objects associated to a simple spatial task that enabled the tested individual to visually interact with an unfamiliar congener (the reward) located behind a transparent wall at the end of one of the two arms of a maze. Ten fish from each origin were individually tested 3 times in a row during 3 days (9 trials in total). Fish were placed in a start box closed by a transparent wall located in front of two 2-D objects. Fish were filmed during 10 min after the removal of the start box wall. Different swimming variables including angular velocity, total distance travelled and velocity mean, were analyzed from videos as well as the time spent in each of 6 virtual zones including the reward zone near the congener (Cong) and the zone opposite to the reward zone (OpCong). Two learning criteria were chosen: the number of successful turns and time to reach Cong. Behavioural differences were found between domesticated and wild fish. Angular velocity was higher in wild fish while the distance travelled and the velocity mean were higher in domesticated ones. Wild and domesticated fish spent most of the time in Cong and in OpCong. No differences were seen in learning ability between wild and domesticated fish. However, our findings for learning require confirmation by further studies with larger numbers of learning sessions and experiments designed to minimise stress. This study therefore demonstrated an impact of domestication on swimming behaviour but not on spatial learning. © 2013 Benham et al. Source


Benhaim D.,British Petroleum | Begout M.-L.,College de France | Chatain B.,Laboratoire Of Recherche Piscicole Of Mediterranee
Journal of Aquaculture Research and Development | Year: 2013

The present work compared wild-caught and domesticated sea bass juveniles swimming activity, exploration and visual attraction induced by an unfamiliar congener located behind a transparent wall at the end of one arm of a T-maze. This cognitive challenge was based on the hypothesis that placed into a novel and therefore stressful environment; the fish would adopt a gregarious behaviour even though they were not familiar with the present congener. Twenty individuals of similar size from both origins were individually tested. After a 5min acclimatization period, the wall of the start-box was removed and the maze was filmed during 20 min. Different swimming variables including angular velocity (Vang), total distance travelled (Dtot), velocity mean (Vel), time spent in Immobility (Im) were analysed from videos as well as the time spent in each of 6 virtual zones including the start-box zone (Start), the zone near the congener (ZCong), the zone opposite to ZCong (OpCong) and three other zones. Vang was higher in domesticated fish and Im higher in wild fish but fish from both origins spent most of the time in ZCong showing a similar visual attraction induced by an unfamiliar congener of similar size. Nevertheless, individual variability was shown, including fish choosing to shelter in Start and fish visually attracted to the congener but located in OpCong. These results demonstrated an impact of domestication on a few swimming activity characteristics but not on gregarious behaviour. The findings are discussed with focus on ecological and aquaculture concerns and their potential interest for future cognition-based experiments on this species. © 2013 Benhaïm D, et al. Source


Benhaim D.,British Petroleum | Pean S.,College de France | Brisset B.,College de France | Leguay D.,College de France | And 2 more authors.
Aquatic Living Resources | Year: 2011

This study aims to test the influence of size grading on self-feeding behaviour, social structure (measured by the percentage of triggering acts per individual), growth performances, and blood physiological variables of individually passive integrated transponder (PIT)-tagged sea bass juveniles, using a computerized on-demand feeding system coupled with a PIT tag monitoring device. Three consecutive periods of 27 days each were compared: a first period (P1) before grading (6 tanks of 100 fish; 40.2 ± 8.9 g) followed by a second period (P2) after grading. The protocol applied aimed to create two groups of fish of similar mean weight but with either a low or a high coefficient of variation of weight (CV w) corresponding to an imposed difference in social disruption (T low: CV w ∼ 10%, 3 tanks of 60 fish each with social disruption; T high:CV w ∼20%, 3 tanks of 60 fish each, without social disruption). T low and T high groups were studied over P2, and an additional 27-day period under identical conditions (P3). The grading protocol used and/or time modified the social structure when comparing P1 and P2. Thereafter, during P2 and P3, no difference could be observed in growth performances, feed demand, or physiological variables between T low and T highgroups. Feeding rhythms and social structures were similar in both groups. In conclusion, such grading practice only transiently modifies feed demand behaviour and social structure built around the self-feeder, without further improvement in individual growth performances in sea bass. © 2011 EDP Sciences, IFREMER, IRD. Source


Benhaim D.,British Petroleum | Begout M.-L.,College de France | Pean S.,College de France | Brisset B.,College de France | And 2 more authors.
Applied Animal Behaviour Science | Year: 2012

In various experiments under self-feeding conditions, sea bass groups could be divided into three categories regarding feeder actuation: high, low and zero-triggering fish. In all cases few high-triggering fish were responsible for a high percentage of the feed delivery. A question was raised about the role played by feeding motivation in such high-triggering status acquisition. It was approached by applying a 3-week fasting period in order to induce similar negative specific growth rate (SGR) in two groups of fish of similar mean weight but with either a low or a high coefficient of variation for weight (CV w) (T low: CV w~11%, 3 tanks of 60 fish each; T high: CV w~20%, 3 tanks of 60 fish each). These groups were created to test the consistency of behavioural responses in two different contexts (i.e. two population size-distributions). During the follow-up period of 40 days, the group level feed-demand behaviour was not strongly modified by the fasting period and there were no differences between T low and T high groups. Complete growth compensation was the same in all tanks as observed at the end of the experiment. At the individual level, high-triggering fish were exactly the same individuals before and after the fasting period. Up to four high-triggering fish could be observed according to the tank and when several fish were performing high-triggering activity, their rankings were sometimes reversed after the fasting period. High-triggering fish increased their activity levels after the fasting period showing behavioural plasticity. High-triggering status could neither be explained by an initial lower SGR nor a sex effect, nor by any of the measured physiological blood parameters. Thus, individual's triggering activity levels could be related to personality and/or metabolic traits but further research is required to confirm this assumption. © 2011 Elsevier B.V. Source


Ferrari S.,College de France | Ferrari S.,CIRAD - Agricultural Research for Development | Benhaim D.,British Petroleum | Colchen T.,College de France | And 3 more authors.
Applied Animal Behaviour Science | Year: 2014

Most studies carried out with seabass under self-feeding conditions report an intriguing social structure that is built around the device and the food dispenser with three coexisting triggering categories: high-triggering (HT), low-triggering (LT) and zero-triggering (ZT) fish. However, neither sex nor feeding motivation or hierarchy can explain the establishment of this specialization. We characterized the personality of seabass with the commonly used restraint and open field tests and assessed the link between personality traits and individual triggering activity towards the self-feeder apparatus. We found no differences between triggering categories during the restraint test but high triggering fish were characterized as shyer than low- and zero-triggering fish during the open field test. Triggering activity was negatively correlated with exploratory capacities and boldness. This experiment provides for the first time evidence that high triggering status in seabass is correlated with personality traits, which could partly explain the social structure that builds around a self-feeder device. © 2014 Elsevier B.V.. Source

Discover hidden collaborations