Showing papers by "Sophie Lumineau published in 2011"

Development of Fearfulness in Birds: Genetic Factors Modulate Non-Genetic Maternal Influences

Abstract: The development of fearfulness and the capacity of animals to cope with stressful events are particularly sensitive to early experience with mothers in a wide range of species. However, intrinsic characteristics of young animals can modulate maternal influence. This study evaluated the effect of intrinsic fearfulness on non-genetic maternal influence. Quail chicks, divergently selected for either higher (LTI) or lower fearfulness (STI) and from a control line (C), were cross-fostered by LTI or STI mothers. Behavioural tests estimated the chicks' emotional profiles after separation from the mother. Whatever their genotype, the fearfulness of chicks adopted by LTI mothers was higher than that of chicks adopted by STI mothers. However, genetic background affected the strength of maternal effects: the least emotional chicks (STI) were the least affected by early experience with mothers. We demonstrated that young animal's intrinsic fearfulness affects strongly their sensitivity to non-genetic maternal influences. A young animal's behavioural characteristics play a fundamental role in its own behavioural development processes.

Influence of a mobile robot on the spatial behaviour of quail chicks

Abstract: Quail chicks encountered an autonomous mobile robot during their early development. The robot incorporated a heat source that stimulated following of chicks. The spatial behaviour of grown-up chicks was tested in an exploration test and a detour test. Chicks that grew with the mobile robot exhibited better spatial abilities than chicks grown with a static heat source. We discuss these results in the perspective of animal–robot interaction and of the role of early spatial experience on the behavioural development.

A place to hide in the home-cage decreases yolk androgen levels and offspring emotional reactivity in Japanese quail.

Abstract: An animal's emotional responses are the result of its cognitive appraisal of a situation. This appraisal is notably influenced by the possibility of an individual to exert control over an aversive event. Although the fact that environment controllability decreases emotional responses in animals is well established, far less is known about its potential trans-generational effects. As the levels of avian yolk hormones can vary according to the mother's environment, we hypothesized that housing environment of mothers would modulate the quality of her eggs and in turn her offspring's behaviour. Two groups of female Japanese quail were constituted: a group that had access to a place to hide in their home-cage (Hd, n = 20) and a group that had nowhere to hide (NoHd, n = 20) when stressed. Both groups were submitted to daily human disturbances for a twenty-day-period. Hd females produced eggs with both less testosterone and androstenedione than did NoHd females. The emotional and social reactivity of Hd females' offspring were lower and their growth was slower than those of NoHd females' offspring. Our results show that a minor difference in housing environment had substantial effects on eggs and offspring. The presence of a shelter probably helped quail to cope with daily human disturbances, producing less reactive offspring. This transgenerational effect caused by an opportunity to hide could lead to applications in care of laboratory animals, conservation biology and animal welfare.

Rhythmic birds show a better social integration than arrhythmic birds.

Abstract: The activity rhythms of Japanese quail vary from one individual to another. Performing a divergent selection, we obtained one line of quail expressing a robust circadian rhythmicity of feeding activity (R) and one line of quail expressing circadian arrhythmicity of feeding activity (A). We questioned whether the endogenous rhythmicity of an individual could predict its integration in a group. For that, we introduced either an R- or an A-line chick into stable groups of standard chicks. First, we evaluated proximity and synchronization of the introduced chicks on the activities of the other group members. R-chicks remained spatially and temporally closer to other group members than did A-chicks. Second, we evaluated interactions of the introduced chicks and the level of their acceptance by the other group members. R-chicks were more competent to gain access to food than were A-chicks, and separation from their group stressed R-chicks more than A-chicks. Last, successive introductions assessed age effects: before, around, and after dispersal time (∼11th day of chicks' life). Most differences between R- and A-chicks were observed between their 7th and 15th day of life. In conclusion, individual endogenous rhythms predict social integration.