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International audience; Parrots are highly social birds that are recognized for their primate-like cognitive abilities but their way to express emotions remain overlooked. Herein we explored potential facial indicators of emotions in cockatoos. We predicted that facial feather ruffling is an indicator of a cockatoo's emotional state and hypothesized that specific facial feather positions would be present more during positive valence and low arousal situations. We observed feather position on the crest, cheek and nape during the daily routine of a group of five captive, non-breeding, Sulphur-crested cockatoos. The data show that cheek and nape feather ruffling occurred significantly more during activities associated with low arousal levels and positive valence such as maintenance behaviours, positive and quiet social contact and resting. Our data suggest that ruffling feathers over the bill (i.e. cheek feather ruffling) and nape ruffling may provide visual indicators of calm/relaxed states in cockatoos. Subtle movement of facial feathers may be an effective close-ranged visual signal to communicate birds' affective states or their intention to engage in specific activities. This work provides a novel approach to assessing the positive welfare of captive cockatoos and to understanding emotional communication in non-mammalian species.

International audience; Regular visual presence of humans is known to reduce chickens' human-generated stress responses. Here we questioned whether, more than mere visual presence, human behaviour affects laying hen behaviour and subsequently their offspring's behaviour. We hypothesized that human behaviour triggers maternal effects via variations in yolk hormone levels. For five consecutive weeks, two groups of hens were exposed to the same durations of human presence (30 min twice a day, five days a week) but the behaviour of the human differed between groups. The first group (H+) was exposed to predictable arrival of the experimenter, slow movements combined with static presence, stroking during handling and human voice. Whereas the second group of hens (H-) was exposed to unpredictable arrival of the experimenter which remained silent, in motion, and did not provide stroking during handling. At the end of the treatment, we evaluated egg quality and offspring behaviour. We found that avoidance of the experimenter by H+ hens but not by H– hens decreased significantly. Fertility rates and concentrations of yolk progesterone and estradiol in H+ hens' eggs were higher than in H– hens' eggs. Fear of humans, neophobia or the capacity to solve a detour task did not differ significantly between H+ and H– chicks. Social discrimination tests showed that H+ chicks but not H– chicks typically preferred a familiar conspecific to a stranger. These results show that, with the same duration in the presence of the birds, humans through their behaviour engender variations in fertility rates, yolk hormone levels and transgenerational effects on social skills. Rarely explored, our data suggest that maternal effects influence filial imprinting. These data have broad implications for laboratory, commercial systems and conservatory programs where the inevitable presence of humans could trigger maternal effects on offspring phenotype.

International audience; The positive aspect of emotions, like pleasure, remains overlooked in birds. Our aim was to contribute to the exploration of facial indicators of positive emotions. To observe contrasting emotional expressions, we used two lines of Japanese quail divergently selected on their inherent fearfulness: a fearful line (long tonic immobility duration: LTI) and a less fearful line (short tonic immobility duration: STI). To induce positive emotions, we gave individual quail the opportunity to perform a rewarding behaviour, dustbathing, in an unfamiliar cage. More STI than LTI quail expressed dustbathing and latencies to dustbathe were significantly shorter in STI than LTI quail. This result indicated that the lines of quail differed in their fearfulness of the situation. We observed crown feather height, throat feather angle and pupil surface before (control) and during dustbathing. We found significant increases in crown feather height, pupil area and angle of throat feathers between the control and the dustbathing phases in STI quail, and pupil area correlated positively with crown feather height. In LTI quail, the angle of throat feathers increased during dustbathing, but the other parameters did not differ. We argue that variation in crown feather height and pupil area may provide indications of positive emotions in Japanese quail.

International audience; Mainly recognized for their cognitive performance, the visual communication system and, particularly, the potential function of facial displays in parrots remain thus far unexplored. Here, we provide the first descriptive study of facial display use in captive blue-and-yellow macaws. We observed the feather position (sleeked or ruffled) on the crown, nape and cheek at the group level during the macaws' daily routine and individually while interacting with a familiar animal caretaker. In the latter context, blushing was also assessed on the bare skin of the cheek. Group level observations showed that crown, nape and cheek feathers ruffling was more frequent in activities requiring no locomotion than in activities requiring locomotion. With the animal caretaker, crown ruffling was significantly more frequent when the caretaker was actively engaging with the parrot than during a control phase with no mutual interaction. In addition, a significantly higher proportion of naive observers judged blushing as being present on photographs taken during the mutual interaction phase than during the control phase. We thus showed significant variations in facial displays and bare skin colour based on the birds' social context and activity. Our results broaden the scope for further studies to determine whether parrots' faces provide visual social signals.

Emotions are recognized as strong modulators of cognitive capacities. However, studies have mainly focused on the effect of negative emotions, with few investigating positive emotions. Recent studies suggest that traits of personality can modulate the effects of emotion on cognitive performance. This study aimed to assess whether emotional states differing according to their valence influenced the ability to achieve instrumental conditioning and learning flexibility and to determine the influence of personality. After being tested for their personality, 55 mares underwent acquisition and extinction procedures of instrumental conditioning in a box previously associated with negative events (e.g., novel and sudden stimuli; E-), positive events (e.g., food reward; E+), or no particular event (E⁰). This contextual conditioning induced contrasting behavioral and physiological responses during acquisition, indicating that E- horses were in a negative and E+ horses were in a positive emotional state. Although acquisition performance did not differ between groups, E+ horses showed a greater flexibility in the extinction phase of instrumental learning than E- and E⁰ horses. Furthermore, fearless personality was related to better acquisition and increased cognitive flexibility. This study demonstrates that horses were able to undergo contextual conditioning that induced negative or more positive emotional states and that this latter emotional state enhanced cognitive flexibility. (PsycINFO Database Record

In this study, we assessed whether prenatal exposure to elevated yolk steroid hormones can influence in ovo chemosensory learning and the behavior of domestic chicks. We simulated a maternal environmental challenge by experimentally enhancing yolk progesterone, testosterone, and estradiol concentrations in hen eggs prior to incubation. The embryos from these hormones-treated eggs (HO) as well as sham embryos (O) that had received the vehicle-only were exposed to the odor of fish oil (menhaden) between embryonic Days 11 and 20. An additional group of control embryos (C) was not exposed to the odor. All chicks were tested following hatching for their feeding preferences between foods that were or were not odorized with the menhaden odor. In the 3-min choice tests, the behavior of O chicks differed significantly according to the type of food whereas C and HO chicks showed no preference between odorized and non-odorized food. Our result suggests weaker response in HO chicks. In addition, HO chicks showed impaired growth and reduced intake of an unfamiliar food on the 24-h time scale compared to controls. Our data suggest that embryonic exposure to increased yolk hormone levels can alter growth, chemosensory learning, and the development of feeding behaviors.

International audience; Chronic stress is considered detrimental for an individual as it is a long-lasting negative emotional state, without or with a limited habituation. The reactivity and sensitivity of animals to stressors depend on the animal's organismic characteristics such as sex. In poultry, the studies dealing with chronic stress were mainly performed on females. Our study then focused on male quail and aimed at assessing the effect of unpredictable and repeated negative stimuli (URNS) on their general activity, tonic immobility, emotional reactivity to a human, a novel object, novel foods or when restrained in a crush cage, as well as on their plasma corticosterone concentrations. Quail were then left undisturbed or submitted to URNS during 6 weeks (n = 12 in each group). The results indicated that disturbed males spent a greater proportion of time far from the human than control ones (on the 1st test, 44.23 ± 5.28 vs 21.80 ± 6.12%, P = 0.01), probably to avoid the human. Disturbed males pecked at the novel object latter (P = 0.03) and less (P = 0.05) than controls. When restrained in a crush cage, disturbed quail were more often motionless than controls (13.49 ± 4.57 vs 4.76 ± 2.11%, P = 0.05). Disturbed quail ate a greater cumulative amount of mealworms (P = 0.05) or ate red maggots with a shorter latency compared to controls (P < 0.05 for the 2nd and 3rd red maggots, on the 2nd test). Concerning the general activity, disturbed males only showed less stereotypic behaviour than control ones after 14 days with URNS (1.4 ± 0.4 vs 4.9 ± 1.2% respectively, P = 0.03), but this difference disappeared after 34 days with URNS (P > 0.1). More importantly, stereotypic behaviours represented less than 5% of the time budget of both groups. URNS had however no effect on tonic immobility, general activity and corticosterone concentrations. This study demonstrated that URNS induced an increase of male quail's emotional reactivity to a human (when tested for the 1st time), to a novel object and when restrained in a crush cage. URNS also altered male quail's feeding behaviour. Disturbed quail were more interested by the novel foods than control quail presumably because they considered them as positive rewards after repeated exposures and they used them as a way to compensate their negative emotional state. All in all, our results demonstrated that URNS induced a chronic stress state in male quail that can have negative consequences on their welfare.

In several mammalian species, prenatal exposure to odours can elicit later positive consummatory behaviour in response to substrates bearing that odorant. In birds, the sense of smell has been considerably underestimated, and very little is known about the effects of early sensory experience on the regulation of feeding behaviour. We tested the hypothesis that the feeding behaviour of the domestic chicken could be regulated by olfactory learning during the embryonic life. To that end, chicken embryos were exposed to an olfactory stimulus (blend of essential oil of orange and nature identical vanillin) from embryonic day (ED) 12 to ED20, and chicks were tested between 4 and 9 d of age. In short-term choice tests, at day 4 and 5, chickens previously exposed to a low concentration (LC) of the olfactory stimulus spent a higher proportion of time eating a familiar or an unfamiliar food bearing the olfactory stimulus compared to non-exposed control chickens. Conversely, chickens previously exposed to a high concentration (HC) of the olfactory stimulus were found to avoid all foods bearing the olfactory stimulus. On a 24- h time scale at day 7-8, LC and HC birds, but not controls, ingest significantly less familiar food containing the olfactory stimulus. This result indicated a long-term effect of the early olfactory experience on feeding preferences. We demonstrated that chickens can utilize information from their pre-hatch chemosensory environment to guide their later feeding behaviour. A pre-hatch effect of the intensity of odour signals in the regulation of feeding behaviour is reported here for the first time.

Repeated encounters with unfamiliar conspecifics in large groups of domestic birds create a potentially stressful social environment which can affect the birds' emotional reactivity and consequently their welfare. As social relationships between young quail are particularly influenced by their social motivation (i.e., the motivation to seek close proximity with conspecifics), it is likely that the reaction of quail to repeated encounters with strangers depends on their social motivation. The aim of this study was to assess the emotional reactivity of quail chicks with high (HSR) or low (LSR) social motivation housed under stable and unstable social conditions. Quail chicks were housed either in stable pairs, i.e. remaining with the same cagemate until testing (N(HSR) = 19 and N(LSR) = 18 pairs), or in unstable pairs, i.e. changing cagemate daily from 6 to 13 days of age (N(HSR) 20 and N(LSR) = 19 pairs). Emotional reactivity was measured using a novel object test on day 14, and an emergence test and a tonic immobility test on day 15. The social condition affected the number of induction attempts of quail chicks in the tonic immobility test but only in the LSR ones. This number of inductions was lower under the stable than under the unstable social condition in this line. Moreover, the HSR chicks showed greater disturbance than the LSR ones in the three behavioural tests. In conclusion, social instability did not affect the emotional reactivity of HSR quail chicks, which was high, regardless of social condition. In contrast, repeated cagemate changes seemed to decrease the emotional reactivity of LSR quail chicks. These results suggest that low social motivation makes easier the adaptation to the potential social instability encountered in large flocks. (c) 2010 Elsevier B.V. All rights reserved.

La notion de bien-être chez l’animal d’élevage n’a de sens que si on lui reconnaît la capacité à ressentir des émotions. Cependant, du fait de l’absence de langage verbal, le vécu émotionnel de l’animal est difficilement mesurable, ce qui a toujours rendu son étude délicate. Les travaux récents en psychologie cognitive montrent combien l’étude des interactions entre émotions et cognition est nécessaire pour accéder aux états affectifs de l’animal et tenter ainsi d’identifier les paramètres susceptibles d’affecter son bien-être. Ce texte comporte deux volets. Le premier volet s’appuie sur les théories de l’évaluation développées chez l’Homme, lesquelles suggèrent que le déclenchement des émotions résulte de processus cognitifs d’évaluation basés sur des critères élémentaires tels que la nouveauté et la prévisibilité. Sur la base de ce cadre théorique, nous avons engagé une approche sur les animaux d’élevage visant à définir les critères d’évaluation qu’ils utilisent, et à faciliter ainsi la compréhension de leurs émotions à partir de l’étude de la combinaison des critères impliqués. Le second volet de ce texte s’appuie sur les nombreuses études menées chez l’Homme et les animaux de laboratoire, qui suggèrent que les émotions peuvent en retour influencer les capacités cognitives de l’individu en altérant ses capacités attentionnelles et mnésiques. L’approfondissement de l’étude des interactions entre émotions et cognition offre donc de nouvelles perspectives de recherche pour mieux comprendre les conditions de bien-être des animaux en élevage., Assessment of farm animal welfare requires a good understanding of the animals' affective experience, including their emotions. However, this is difficult to measure because of the absence of verbal communication. Recent studies in the field of cognitive psychology have shown that affective states can be assessed through investigation of the interactions between emotions and cognition. On the one hand, theories of the way humans appraise situations provide a conceptual framework that suggests that emotions are triggered by cognitive appraisal processes based on few elementary criteria such as novelty and predictability. In accordance with appraisal theories, we have developed an experimental approach to study the elementary criteria used by farm animals to evaluate their environment and then express a given emotional response. On the other hand, an increasing number of studies in humans and animals suggest that emotions also influence cognitive processes by modifying attention, memory and judgement. Measurement and manipulation of cognitive processes may provide new insights into how emotions and more persistent affective states in animals can be assessed. Further work on these cognitive approaches will offer new paradigms for a better understanding of the welfare of farm animals.

Furnished cages for laying hens exist in a wide variety of sizes and designs and should be equipped to allow hens to express some of their behavioural priorities. European Council Directive 1999/74/EC stipulates that litter must be provided for pecking and scratching but the type of litter and the pad where litter is delivered are not defined. In the same way, neither the maximum nor the optimum number of birds per cage has been defined. Two successive experiments were carried out to analyse pecking, scratching (PS) and dustbathing (DB) behaviours performed in different furnished cages with different designs. Three group sizes of ISA brown laying hens (20, 40 or 60 hens, with the same density in all the cages), with or without additional feed distribution as litter substrate, were compared in the first experiment. The second experiment focussed on DB behaviour and compared two pecking and scratching pads (artificial turf or rubber mats), with or without wheat bran distribution as litter substrate, in groups of 60 hens per cage. Irrespective of litter presence, group size, and type of pad, DB and PS were mainly performed in the pecking and scratching area, showing the attractiveness of this area. In the first experiment, feed–litter provision in pecking and scratching area increased PS and DB behaviours, while group size did not affect them. In the second experiment, hens performed more DB in the pecking and scratching area when wheat-bran litter was present than when it was absent. Rubber matting was more attractive to hens for DB than artificial turf matting. Durations of DB bouts were not affected by the presence or absence of wheat-bran litter or the choice of pecking and scratching pad. In furnished cages, hens clearly seek out pads and litter to perform PS, and providing litter (feed or wheat bran) or rubber in pecking and scratching area is attractive for hens to DB in it. However, the cage design could be improved to promote more DB activity, for instance by increasing space of pecking and scratching area in the cage.

In birds there is compelling evidence that the development and expression of behavior is affected by maternal factors, particularly via variation in yolk hormone concentrations of maternal origin. In the present study we tested whether variation in yolk hormone levels lead to variation in the expression of neophobia in young domestic chicks. Understanding how the prenatal environment could predispose chicks to express fear-related behaviors is essential in order to propose preventive actions and improve animal welfare. We simulated the consequences of a maternal stress by experimentally enhancing yolk progesterone, testosterone and estradiol concentrations in hen eggs prior to incubation. The chicks from these hormone-treated eggs (H) and from sham embryos (C) that received the vehicle-only were exposed to novel food, novel object and novel environment tests. H chicks approached a novel object significantly faster and were significantly more active in a novel environment than controls, suggesting less fearfulness. Conversely, no effect of the treatment was found in food neophobia tests. Our study highlights a developmental influence of yolk hormones on a specific aspect of neophobia. The results suggest that increased yolk hormone levels modulate specifically the probability of exploring novel environments or novel objects in the environment.

International audience; Animals perceiving repeated aversive events can become chronically stressed. Chronic activation of the hypothalamic-pituitary-adrenal (HPA) axis can have deleterious consequences on physiological parameters (e.g. BW, blood chemistry) and behaviour (e.g. emotional reactivity, stereotypies, cognition). Environmental enrichment (EE) can be a mean to reduce animal stress and to improve welfare. The aim of this study was first, to assess the effects of EE in battery cages on the behaviour of young Japanese quail and second, to evaluate the impact of EE on quail exposed to chronic stress. The experiment involved quail housed in EE cages and submitted or not to a chronic stress procedure (CSP) (EE cages, control quail: n=16, CSP quail: n=14) and quail housed in standard cages and exposed or not to the CSP (standard non-EE cages, control quail: n=12, CSP quail: n=16). Our procedure consisted of repeated aversive events (e.g. ventilators, delaying access to food, physical restraint, noise) presented two to five times per 24 h, randomly, for 15 days. During CSP, EE improved quail's welfare as their stereotypic pacing decreased and they rested more. CSP decreased exploration in all quail. After the end of CSP, quail presented increased emotional reactivity in emergence test. However, the effect of EE varied with test. Finally, chronic stress effects on comfort behaviours in the emergence test were alleviated by EE. These results indicate that EE can alleviate some aspects of behavioural alterations induced by CSP.

Young domestic fowl chicks, Gallus gallus domesticus, discriminate between familiar and unfamiliar agemates. We investigated the retention of individual discrimination and the effects of social experience on such recognition memory. In the first series of experiments, chicks were paired with an initial social partner (I) for 22.5 or 42 h. These I pairs were then separated and each chick was housed with a new partner (Recent: R) for about 19 h. During subsequent tests, interactions between I partners did not differ from those of unfamiliar test pairs. However, chicks in R pairs pecked at their partners less frequently during the test trials and spent more time in physical contact than did unfamiliar pairs. Chicks in two additional experiments were similarly housed in pairs with an initial partner, then either isolated or housed with a new partner in an unlit room. After these treatment procedures, chicks in both experiments pecked at lower frequencies when tested with their I partner compared to an unfamiliar agemate. We conclude that retention of a memory trace of a social partner depends upon the chicks' intervening experience during the separation period. Exposure to a second individual interferes with the recognition memory of the first partner. Furthermore, the negative effect of the second partner on the retention of a memory trace of a previous partner depends on familiarization with the second partner's visual phenotype.

Since 2012 in the EU, cages for the housing of laying hens must provide nests, perches and a pecking and scratching area to promote natural behaviours and enhance animal welfare. Previous studies highlighted the difficulty of finding adequate materials for pecking and scratching areas in such cages, mainly due to hygiene problems and technical constraints. This study investigates whether alternative materials could stimulate dustbathing (DB), pecking, and scratching behaviours and examines if hens show any preferences for these materials compared to other well-known litter materials such as sand, peat and artificial turf. We set up two separate experiments: one to simultaneously compare four litter materials (wheat bran, sand, shell sand and peat) and one to simultaneously compare four alternative non-litter, pad-type solutions (plastic mat, artificial turf mat, a slightly friable experimental block made of wood and oyster shells, and a slightly friable experimental sand block). For each experiment, 15 groups of four hens were observed over four days in a multiple choice test. Wheat bran was found to promote pecking and scratching behaviours better than the other litters. Peat induced more dustbaths than wheat bran but duration of DB bouts was similar for both materials. However, the number of dustbaths in wheat bran increased throughout the test, while the duration of DB bouts decreased in peat, showing an increasing preference for wheat bran. The shell sand was found to be the least preferred for pecking, scratching and DB. In the second experiment, pads were found to be less attractive than litters for pecking, scratching, and DB. The plastic mat was very rarely used for DB compared to other solutions in the pad choice test. As hens rarely pecked or scratched any of the pads, no significant differences were noted between the four different types. However, experimental blocks stimulate DB as much as artificial turf mats and seem promising, as their use for DB increased throughout the test. This study shows that wheat bran could be an optimal litter for use in furnished cages to improve hen welfare. In addition, research on new experimental blocks is worth being developed, as it has the advantage of not needing to be renewed during a laying period.

Compared to rodents, the relationship between anxiety and cognitive performances has been less studied in birds. Yet, birds are frequently exposed to stimulations that constitute a potential source of anxiety and can affect their adaptation to their living conditions. The present study was aimed at evaluating, in birds, the relationship between levels of anxiety and object habituation and discrimination with the use of Japanese quail lines divergently selected for a fear response, tonic immobility. Previous studies demonstrated that the selection programme has modified the general anxiety trait of the birds. The task consisted in 4 daily sessions of 8 successive presentations of the same object in the home cage of the quail in order to habituate each bird to the object. The observation that both quail with a high and a low anxiety trait progressively spent more time close to the object indicated that habituation occurred. Dishabituation was assessed during a single session of 8 presentations of a novel object. Only quail with a high anxiety trait exhibited significant discrimination. They spent significantly less time close to the novel object than to the habituated object. It is hypothesised that a high anxiety trait is associated with a more accurate processing of environmental cues or events resulting in better discriminative performances.

This study tested whether lines of Japanese quails divergently selected for a fear response, the tonic immobility, might constitute a reliable bird model for studying anxiety. Previous studies demonstrated that the selection modifies the general underlying emotionality of the birds rather than exerting its effect only on tonic immobility. The behavioural effects of intraperitoneal injections of diazepam, an anxiolytic drug, were assessed in two lines of quail selected either for their short (STI) or long (LTI) duration of tonic immobility. Effects of diazepam were examined in two tests used for measuring emotionality in birds, the open field and the tonic immobility tests. After being placed in the centre of the open field, birds with a high emotionality (LTI quails) stayed longer in the centre of the apparatus than STI quail. Diazepam had anxiolytic effect in LTI birds as it increased the time spent in the outer area. This effect of diazepam appears to be selective because the drug has no effect on other behaviours such as distress calls or escape attempts. The drug has also no effect on the tonic immobility response in any of the two lines. These findings reveal an “anxiogenic” trait of LTI birds in the open field test that can be modulated by the administration of an anxiolytic drug. Therefore quails selected for LTI and STI represent a valuable model to study the mechanisms underlying anxiety in birds.

International audience; Chronic stress is known to enhance mammals' emotional reactivity and alters several of their cognitive functions, especially spatial learning. Few studies have investigated such effects in birds. We investigated the impact of a two-week stress on Japanese quail's emotional reactivity and spatial learning. Quail is an avian model widely used in laboratory studies and for extrapolation of data to other poultry species. As sensitivity to chronic stress can be modulated by intrinsic factors, we tested juvenile female Japanese quail from three lines, two of them divergently selected on tonic immobility duration, an indicator of general fearfulness. The different emotional reactivity levels of quail belonging to these lines can be revealed by a large variety of tests. Half of the birds were submitted to repeated unpredictable aversive events for two weeks, whereas the other half were left undisturbed. After this procedure, two tests (open field and emergence tests) evaluated the emotional reactivity of treated and control quails. They were then trained in a T-maze for seven days and their spatial learning was tested. The chronic stress protocol had an impact on resting, preening and foraging in the home cage. As predicted, the emotional reactivity of treated quails, especially those selected for long tonic immobility duration, was higher. Our spatial learning data showed that the treatment enhanced acquisition but not memorization. However, intrinsic fearfulness did not seem to interact with the treatment in this test. According to an inverted U-shaped relationship between stress and cognition, chronic stress can improve the adaptability of birds to a stressful environment. We discussed the mechanisms possibly implied in the increase of emotional reactivity and spatial abilities.

Social bonds between groupmates and social motivation can influence the stability of the social structure among domestic birds. Group size may also influence social stability, but no information is available about its influence on social bonding. We investigated the effect of group size and social motivation on the strength of social bonds between familiar Japanese quail chicks. The behaviour of quail selected for high (HSR) or low (LSR) social reinstatement behaviour and housed in different group sizes (6, 15 and 30 individuals) was recorded during two successive 10 min situations: separation and return of a cagemate or an unfamiliar conspecific. In both lines and for all group sizes, chicks formed social bonds with cagemates, shown by disturbance at separation and a greater calming effect of the return of a familiar versus an unfamiliar quail. LSR chicks might form stronger social bonds than HSR ones but our results do not allow us to conclude confidently on that point. With increasing group size, the calming effect and especially the positive social interactions decreased in both lines, indicating a weakening of the social bond between familiar conspecifics, perhaps because of the larger number of potential partners or the establishment of a tolerant social strategy based on less aggression, less time spent in contact and weaker bonds. Further investigations of the relationship between group size and social bonding in this species may allow us to determine why their social behaviour changes with increasing group size and to make more suitable social environments for domestic birds.

Chronic stress is known to induce long term alterations of emotional behaviours as well as cognitive performances leading thereby to welfare or husbandry problems. These stress-induced consequences are observed following long periods of stress lasting from several weeks to several years. The current study examined whether a shorter period of stress (one week) produced similar impairing effects. Two-week old Japanese quail were either submitted to a series of aversive events over consecutive 8 days, at unpredictable times each day (treated animals) or left undisturbed (controls). Following the treatment period, animals were weighed and basal as well as aversive events-induced levels of plasma corticosterone were quantified. Quail were also tested for emotional reactivity in three tests (the tonic immobility test, the hole-in-the-wall and novel object tests) and for spatial reference memory. Although there was no difference in corticosterone levels between the two groups, the treated animals had lower body weight than controls. Behavioural investigations after the treatment period did not reveal any difference between the groups in the three emotional reactivity tests. In the spatial task, treated quail displayed enhanced behavioural flexibility as revealed by their higher performances during the reversal phase of the task. The alteration of growth suggests that a short period of repetitive exposures to unpredictable aversive events can be perceived by quail as stressful. Such a stress period can improve spatial learning performances in quail supporting the critical role played by the duration of the stress period on cognitive performance. (C) 2010 Elsevier B.V. All rights reserved.

International audience; Social bonds between conspecifics (sexual pairmates, parent-infant or siblings) and social motivation can influence the way birds interact. Social bonds between familiar conspecifics may also be formed, especially in chicks from precocial species in which behaviour is characterized by a strong social attraction. We investigated the establishment of such a bond and the effect of social motivation using a separation/reunion test in 1-week-old Japanese quail. In experiment 1, the behaviour of paired quail selected for high (HSR) or low (LSR) social reinstatement behaviour was recorded during three successive 10 min situations: baseline, separation and return of the cagemate. Both lines showed behavioural changes during social separation but the distress response was higher in the HSR line. Return of the familiar cagemate induced a return to baseline activity in both lines. The specificity of this response was tested in experiment 2 in which paired quail of both lines were separated, and their behavioural and vocal responses to the introduction of the familiar or an unfamiliar bird were compared. LSR chicks responded differently both behaviourally and vocally according to the familiarity of the introduced bird, whereas the response of HSR chicks differed only for aggressive pecks. HSR quail chicks thus revealed a nonspecific social attraction for conspecifics, whereas LSR chicks showed a bond with the cagemate. Our results highlight the importance of vocal communication as an indicator of the strength of the bond. Our findings show that high social motivation in quail chicks is not related to the development of a social bond.

WOS:000272361400006; International audience; This experiment explored links between individual social traits and behavioural rhythms by comparing the feeding activity rhythms of HSR (high social reinstatement) Japanese quail that will cover long distances to reach conspecifics, to those of LSR (low social reinstatement) quail that will cover only short distances to reach conspecifics. We evaluated the functioning of their circadian and ultradian clocks under constant darkness (M), and then under photoperiodic conditions (LD). Our results revealed that, under DO conditions, the circadian periods of HSR quail were closer to 24 h than those of LSR quail. Under LD conditions, the daily rhythm of HSR quail was clearer than that of LSR quail. HSR quail synchronized faster and better to the environmental LD cycle than LSR quail. Our results also showed that, under DID conditions, more LSR than HSR quail expressed ultradian rhythmic phenotypes and that the ultradian rhythm of LSR quail was clearer than that of LSR quail. Under LD conditions, these differences between HSR and LSR quail showed the same tendencies. LSR quail seem to present a more functional ultradian system, and thus could possibly synchronise better on an ultradian environmental cue than HSR quail. Our study demonstrated a link between individual rhythmicity and social traits at an intra-specific level. It revealed complex relationships between ultradian, circadian, and daily rhythms and level of social motivation in Japanese quail.

International audience; A simultaneous two-choice test was used to investigate discrimination between a familiar (F) and an unfamiliar conspecific (U) in Japanese quail, selected for high (HSR) or low (LSR) social reinstatement behavior (tendency to rejoin and stay close to conspecifics). Animals were 1-week unsexed and 6-week-old male quail. One-week-old LSR quail and 6-week-old male HSR quail displayed discrimination after 24 hr of pair contact (P < 0.05), and a tendency to discriminate (p < 0.10) was found in adult male LSR quail. After I week of pair contact, results were similar in LSR quail chicks, but no discrimination was evidenced in adult quail of either line. Therefore, Japanese quail are able to discriminate between a familiar cagemate and an unfamiliar conspecific after only 24 hr of pair contact. Moreover this study reveals for the first time in this species that social motivation and age both influence the display of individual discrimination. (C) 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 311-321, 2009.

The reaction of ewes to food treated with amniotic fluid (AF) from other ewes, cows and goats, vs. untreated food (control) was tested around the time of parturition (from 24 h before until 4 h after parturition). Nine ewes were tested with both bovine and ovine AF and 12 additional ewes were tested with both caprine and ovine AF. Results confirm our previous study showing a repulsion in response to ovine AF before lambing, and an attraction toward this fluid at parturition that continues for at least 4 h. Ewes also appeared to be strongly repelled by bovine AF at all times as they never ate from the trough containing that fluid. Prior to parturition, ewes were also repelled by caprine AF: only two out of 12 females ate food damped with AF. This repulsion disappeared at parturition: nine out of 12 females ate from the AF trough. However, ewes spent more time consuming food mixed with ovine than with caprine AF (P = 0.01), indicating that they were more attracted to the former substance. Interest for caprine AF decreased 4 h after parturition, with only three out of 11 ewes feeding from the AF trough. The implications of the results for the possibility of fostering between species of ungulates were discussed.

International audience; In intensive rearing, birds are exposed to frequent changes in both their social and physical environments, and this can have an impact on animal welfare under commercial conditions. The aim of the present study was to compare the emotional responses induced by social and non-social changes and to study the influence of the familiarity on these responses.Twenty-two female quail were first reared with a ball in 15–20-individual groups for 3 weeks from hatching. Then, each experimental subject was allocated either a familiar congener (CONG) or a familiar object (BALL). At 6 weeks of age the birds were fitted with a telemetric device to collect motor and cardiac activities. After that, each subject was exposed first to a separation from its cage-mate/familiar object, and secondly to the (re-)introduction of either the cage-mate/familiar object or of an unknown conspecific/another ball. Emotional responses were assessed through behavioural reactions and heart rate variability.Before being separated, both BALL and CONG quail showed stereotyped pacing that was more pronounced in BALL quail. BALL quail were not affected by the ball withdrawal, unlike CONG quail which reacted to the separation from their cage-mate by reducing activity and exploratory behaviour (P < 0.05). After the re-introduction, BALL quail remained closer to their ball and CONG quail spent more time with “stretched necks” than before the separation (P < 0.05). Surprisingly, CONG quail showed less stereotyped pacing when their partner was removed and recovered the initial level of stereotyped behaviour when their cage-mate was re-introduced (P < 0.01). Likewise, CONG quail also recovered the initial values of heart rate after the re-introduction of their cage-mate, indicating an increase in sympathetic activity compared to the isolation period. When the unfamiliar congener or ball was introduced in their cage, BALL quail pecked the unknown ball more than the familiar ball and had more contact with it (P < 0.05) and CONG quail had more contact with the unknown congener than with the cage-mate (P < 0.05).In conclusion, the quail appeared to experience a negative affective state before being separated, and there was no clear evidence of negative emotion in quail in response to the separation from either a social partner or an inanimate object. Nevertheless, the emotional responses of the quail in reaction to the (re-)introduction was influenced by the familiarity of the congener or the ball. Finally, changes in the quail's social environment induced more behavioural and cardiac modifications than changes in its non-social environment.

This study examined the capacity of young Japanese quail to discriminate between a familiar cagemate (F) and an unfamiliar conspecific (U). Two tests of discrimination were initially compared: a simultaneous double choice test and a pair test allowing social pecking. Discrimination was more clearly demonstrated in the choice test, which was, therefore, used in the subsequent experiments. One-day-old chicks that had been housed in pairs after hatching spent significantly more time near F than a U stimulus bird and more frequently approached and attempted to interact with F. Seven-day-old chicks that were raised in large groups for the first 6 days, then in pairs for 24 h, subsequently displayed no significant differences in their responses to their recent pair partner versus an unfamiliar chick. On the other hand, chicks that were raised in pairs for 6 days, then housed with a new partner (F) for 24 h, more frequently approached and attempted to interact with F than a U bird. These results show that 24 h of pair contact beginning at hatching or 6 days of age is sufficient for quail to discriminate between a familiar cagemate and a stranger. This discrimination ability is influenced by the chicks' early social experience.

International audience; Many studies have shown how laying aviaries can improve hens' welfare, but little work has been done on the adaptation of hens to this system according to their previous rearing conditions, despite the specific adaptation skills it requires of them. The adaptation to laying aviaries of hens previously reared in different conditions was assessed here through their use of vertical levels, numbers and distances of flights and jumps (in week 20 after transfer and, only in rearing aviaries, in week 15 before transfer), eggs location and laying rate (from weeks 18 to 27 after transfer) and mortality (from weeks I to 27). Twelve batches of 282-308 ISA Brown hens were reared from 1 day to 17 weeks of age in floor pens furnished with platforms and perches with manual feed hoppers on litter (FH hens), in rearing aviaries with platforms and manual feed hoppers on litter (AH hens), or in rearing aviaries with automatic chain troughs on platforms (AC hens). Hens in each of these treatments were then transferred to similar laying aviaries with automatic chain troughs on platforms. The FH hens used upper levels less, showed lower accuracy in long flights and jumps and displayed a preference for staying on litter and lower levels, compared with AH and AC hens. They laid fewer eggs inside nest boxes during the first 2 weeks of lay, laid more eggs on litter throughout the observed period, and had a lower onset of laying than AH and AC hens. The FH mortality rate was higher than that of AC hens after transfer, and higher than that of AH and AC pallets before transfer. AH pullets used the lower levels more and made more and longer flights than AC pullets before transfer, but these differences did not persist after transfer. Mortality rates did not differ between AH and AC pullets before transfer, whereas it was higher in AH hens after transfer. AH hens laid slightly more eggs inside nest boxes and had a similar laying rate to AC hens. The present study shows that the design of rearing pens largely influences adaptation: rearing aviaries ensured a better adaptation than furnished floor pens. On the other hand, the feeding system used during the rearing period, particularly troughs location, largely influenced the use of space before transfer, but only slightly influenced the adaptation after transfer in laying aviaries: higher vertical distance between feed and water ensured a better adaptation. (C) 2007 Elsevier B.V. All rights reserved.

International audience; Most tests used to study fear in birds involve transferring them to a novel environment, which constitutes a bias in studies aiming at identifying the neural correlates of a specific fear-inducing situation. In order to investigate fear in birds with minimum interference by humans, behavioural and endocrine responses to the presentation of a novel object in the home cage were investigated in two lines of Japanese quail divergently selected for long or short duration of tonic immobility, a behavioural index of fear. Presentation of the novel object induced typical fear responses (avoidance of the object, increased pacing and increased plasma corticosterone levels) that were similar in the two lines of quail. Presentation of a novel object in the home cage thus appears to be a suitable stimulus to induce fear reactions in quail, with minimum interference from other motivational systems. The fact that quail of both lines reacted similarly in this test, while they are known to differ greatly in their behavioural responses to other fear-inducing tests, illustrates the multidimensional nature of fear. (C) 2007 Elsevier B.V. All rights reserved.

New housing systems for commercial egg production, furnished cages and non-cage systems, should improve the welfare of laying hens. In particular, thanks to the presence of a litter area, these new housing systems are thought to satisfy the dust-bathing motivation of hens more than in conventional cages, in which no litter area is present. However, although apparently obvious, there is no concrete evidence that non-cage systems, particularly aviaries, satisfy hens' motivation to dust-bathe and thus improve hens' welfare in terms of dust-bathing behaviour. The aim of this study was to compare hens' dust-bathing motivation when housed for a long time under similar conditions to commercial conditions in laying aviaries (with litter) and in conventional cages (without litter). Three treatments were compared: hens reared in floor pens then housed in conventional cages, hens reared in furnished floor pens then housed in a laying aviary, and hens reared in rearing aviaries then housed in a laying aviary. All three treatments provided access to litter during the rearing period. After transfer to the laying systems, access to litter was maintained for the aviary hens but stopped for the cage hens. Twelve groups of four hens per treatment were tested 36 to 43 weeks after transfer. The hens were placed in sawdust-filled testing arenas, and latency to dust-bathe, duration and number of dust baths, and number of hens dust-bathing were recorded. Latency to dust-bathe was shorter, dust baths were longer and more numerous and more hens dust-bathed among cage hens than among aviary hens. Our results indicate that hens' motivation to dust-bathe was more satisfied in laying aviaries than in conventional cages. Thus, laying aviaries improve hens' welfare in term of dust-bathing behaviour compared with conventional cages.

We conducted a series of experiments to investigate the temporal development and sensory basis of social discrimination by young chicks, Gallus gallus domesticus . In the initial experiment, 1-day-old chicks were housed in pairs for 6–9 or 11–14 h. After this treatment period, interactions between paired chicks that had been housed together for 6–9 h did not differ from those of unfamiliar chicks. However, pairs of chicks that had been together for 11–14 h pecked each other significantly less than did unfamiliar pairs. Reduced pecking by the familiar partners indicates that 11–14 h of direct contact is sufficient for the establishment of individual discrimination. In a second experiment we assessed the role of olfaction in the development of social discrimination. Chicks in the anosmic condition were housed in pairs after their external nares were blocked with acrylic cement. Control chicks had cement applied to the beak (the nares remained uncovered) before being housed in pairs. When tested after the pair-housing period, pecking frequencies were lower among familiar cagemates than among unfamiliar pairs of chicks in both the anosmic and control conditions. Anosmic chicks, unlike the controls, showed little reaction to mint odour, thereby verifying that the blocked-nares treatment disrupted olfactory perception. In a final experiment, there was no reliable difference between the pecking rates of paired chicks that had been housed together in the dark and those of unfamiliar dark-reared pairs. We conclude that access to social partners' visual phenotype, but not olfactory familiarization, is necessary for the rapid development of individual discrimination by chicks.

Abstract The present study examined whether prenatal chemosensory experience influenced chemosensory-based orientation behaviour in newly-born lambs. Two experimental strategies were developed in order: (i) to analyse the responsiveness of lambs to odours extracted from the prenatal environment (experiments 1 and 4) and to odours their were never exposed to (experiment 2), and (ii) to analyse the neonatal consequences of a prenatal exposure to a novel odorant (experiment 3). In experiment 1, when simultaneously presented with amniotic fluid (AF) and distilled water in a double-choice test, lambs displayed a clear attraction to AF. In experiment 3, two groups of lambs received differing exposure to citral in utero: group I lambs were born to ewes fed a citral diet and group 2 lambs were born to ewes never exposed to citral (CI). They were assessed in a double-choice test contrasting CI and AF (experiment 2 indicates that CI was neither attractive nor aversive in naive lambs). Although control lambs showed a clear preference for AF over CI, those exposed to CI prenatally did not orient discriminately to either stimulus, suggesting that prenatal experience with CI may alter postnatal responsiveness to it. Experiment 4 tested the ability of lambs to discriminate between the chemosensory qualities of samples of own vs alien AF; lambs oriented preferentially to their own AF. These findings suggest that prenatal chemosensory experience may be stored by lambs for some time after birth and influence their search behaviour.