Postnatal care generates phenotypic behavioural correlations in the Japanese quail

International audienceBehavioural phenotypes can be highly constrained by interdependent behavioural traits. Studies in different taxa showed that these behavioural phenotypic correlations are not universal within a species and can differ between populations exposed to different environmental pressures. Empirical studies are required to better understand the relative contributions of long-term adaptive processes and direct ontogenetic mechanisms in the development of these phenotypic behavioural correlations. In the present study, we investigated the role of postnatal nurturing care on the development of behavioural correlations in a precocial bird model, the Japanese quail (Coturnix coturnix japonica). We compared phenotypic correlations between two populations: 41 artificially reared birds (maternally deprived) and 36 birds fostered by unrelated females. Behavioural responses were measured at the age when birds naturally disperse, with three widely used behavioural tests to assess fearfulness and sociality: tonic immobility, open-field and emergence tests. Our results show that when quail chicks are reared by a foster mother, more phenotypic correlations appeared in the population including correlations within and across behavioural functions and between behavioural responses and chick mass. In contrast, chicks reared without a foster mother presented much fewer behavioural correlations and those were limited to functionally linked behaviours. Our results also highlight that the effect of mothering on phenotypic correlations is sex-specific, with a greater effect on males. We discuss the organisational role of parents on the development of behavioural correlations, the mechanisms likely to support this influence, as well as the reasons for sexual dimorphism

Fearfulness Affects Quail Maternal Care and Subsequent Offspring Development

International audienceOur study investigated relationships between a precocial bird’s fearfulness and maternal care, and the implication of maternal care as a vector for non-genomic transmission of fearfulness to chicks. We compared care given to chicks between two sets of female Japanese quail selected to present either high (LTI) or low fearfulness (STI). Chicks, from a broiler line, were adopted by these females following a sensitization procedure. Chicks’ fearfulness after separation from their mother was assessed by well-established procedures. LTIs took longer to present maternal responses, pecked chicks more during the first days post-hatch, presented impaired maternal vocal behaviour and were globally less active than STI females. Chicks mothered by LTIs presented more fearful reactions than did chicks mothered by STIs, supporting the hypothesis of a non-genetic maternal transmission of fearfulness. We suggest that the longer latencies required by LTIs to become maternal are a consequence of their greater fear of chicks, and that their lower general and vocal activity could be components of a heightened antipredatory strategy. We discuss the transmission of maternal fearfulness to fostered chicks, taking into account the possible implication of several well-known mechanisms underlying maternal effects

A Place to Hide in the Home-Cage Decreases Yolk Androgen Levels and Offspring Emotional Reactivity in Japanese Quail

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

Age Affects the Expression of Maternal Care and Subsequent Behavioural Development of Offspring in a Precocial Bird

Variations of breeding success with age have been studied largely in iteroparous species and particularly in birds: survival of offspring increases with parental age until senescence. Nevertheless, these results are from observations of free-living individuals and therefore, it remains impossible to determine whether these variations result from parental investment or efficiency or both, and whether these variations occur during the prenatal or the postnatal stage or during both. Our study aimed first, to determine whether age had an impact on the expression of maternal breeding care by comparing inexperienced female birds of two different ages, and second, to define how these potential differences impact chicks’ growth and behavioural development. We made 22 2-month-old and 22 8-month-old female Japanese quail foster 1-day-old chicks. We observed their maternal behaviour until the chicks were 11 days old and then tested these chicks after separation from their mothers. Several behavioural tests estimated their fearfulness and their sociality. We observed first that a longer induction was required for young females to express maternal behaviour. Subsequently as many young females as elder females expressed maternal behaviour, but young females warmed chicks less, expressed less covering postures and rejected their chicks more. Chicks brooded by elder females presented higher growth rates and more fearfulness and sociality. Our results reveal that maternal investment increased with age independently of maternal experience, suggesting modification of hormone levels implied in maternal behaviour. Isolated effects of maternal experience should now be assessed in females of the same age. In addition, our results show, for first time in birds, that variations in maternal care directly induce important differences in the behavioural development of chicks. Finally, our results confirm that Japanese quail remains a great laboratory model of avian maternal behaviour and that the way we sample maternal behaviour is highly productive

Les Rythmes comportementaux : variabilité, déterminisme et fonctions

National audienc

Rythmes et comportements

International audienc

Rythmes comportementaux et influences maternelles: Caractérisation des rythmes circadiens et ultradiens, et effets maternels postnataux chez un modèle d'oiseau nidifuge, la caille

International audienceTout phénomène biologique, qu''il soit physiologique ou comportemental, n''est pas constant dans le temps. Par stratégie évolutive, les organismes ont intégré de manière endogène des rythmes biologiques en réponse aux variations prévisibles et cycliques de l''environnement dans lequel ils vivent. Ces rythmes biologiques, dont l''étude a longtemps été négligée, représentent donc une fonction fondamentale du monde vivant. La chronobiologie est une discipline en plein essor qui s''attache à répondre à de multiples préoccupations sociétales (chronomédecine, rythmes scolaires, décalages horaires...). Ce livre est une synthèse de travaux qui, dans ce contexte scientifique, cherche in fine à mieux comprendre les phénomènes rythmiques, avec une approche résolument éthologique. Ce travail s''est attaché à caractériser les rythmes de comportement (circadiens et ultradiens) chez un modèle d''oiseau nidifuge, la caille, et d''établir comment la mère, du fait de son importance au cours des premiers stades de vie, va influencer la mise en place des rythmes de ses jeunes. Les effets maternels ont aussi été étudiés sur d''autres caractéristiques comportementales liées au tempérament de l''individu

Leçon de lumière

Conférence plénièreNational audienc

L’ontogenèse des comportements : évolution des concepts d’éthogenèse depuis les années 60

National audienceDans son article fondateur « On aims and methods of ethology » en 1963, Nikolaas Tinbergen énonce comme un des 4 axes principaux d’études d’un éthologiste, celui de l’ontogenèse des comportements. A cette époque, le débat de l’inné et de l’acquis reste encore vif, de même que celui des théories développementales. En effet, la théorie de la préformation des comportements est bien soutenue et préconise un développement unidirectionnel du génotype vers la sortie comportementale. Il faudra attendre les études originales de Gottlieb (1973) sur l’embryogenèse des comportements et les effets de l’expérience précoce sur le développement postnatal des comportements chez les oiseaux nidifuges pour amorcer un changement de direction de pensée. Il émet la théorie de l’épigenèse probabiliste qui propose que le comportement se met en place sous les effets bidirectionnels entre génotype, comportement et environnement. Depuis les années 90, l’évolution des techniques moléculaires a permis d’éclairer certains mécanismes en faveur de cette théorie. Ces mécanismes épigénétiques, démontrés par Meaney chez le rongeur, restent une préoccupation actuelle de nombreux chercheurs, car ils constitueraient une voie de transmission intergénérationnelle des traits comportements, qui expliquerait des processus d’adaptation évolutive des espèces à des changements environnementaux. La contribution de Raymond Campan dans ces débats a été fondamentale, par des travaux sur l’ontogenèse des comportements chez le grillon, et surtout par les synthèses écrites et largement relayées dans la communauté française qui en font des supports d’une indéniable qualité pour la compréhension des évolutions théoriques sur l’éthogenèse

Rythmes et comportements

International audienceQu’est-ce que l’éthologie, ses concepts, ses méthodes ? Comment l’animal utilise son espace, exploite les ressources alimentaires, construit son monde social ? Quelle est la nature des processus cognitifs à l’oeuvre ? Quelle est la part explicative de la personnalité dans le comportement ? Volontairement accessible et pédagogique, supporté par de nombreuses illustrations, cet ouvrage propose des réponses synthétiques à partir de l’analyse des recherches les plus actuelles en éthologie. Il présente la particularité d’exposer, par plusieurs chercheurs spécialistes d’un domaine, outre les thématiques classiques de l’éthologie, les différentes méthodologies de cette discipline et certains concepts nouveaux comme celui de la personnalité animale. Éthologie animale s’adresse principalement aux étudiants en biologie et en psychologie ainsi qu’aux chercheurs et enseignants-chercheurs désireux de découvrir ou d’approfondir leur connaissance du comportement animal