Captive Blue-and-yellow macaws (Ara ararauna) show facial indicators of positive affect when reunited with their caregiver.

In mammals, human-animal bonding is recognized as a source of positive affect for companion or farm animals. Because this remains unexplored in birds, we investigated captive parrots' perspective of the human-animal relationship. We used a classical separation-reunion paradigm and predicted that variations in parrots' facial displays and behaviours would indicate their appraisal of the relationship. The test was divided into three phases of two minutes each: the bird was placed in an unfamiliar environment with a familiar caregiver (union), then the bird was left alone (separation) and finally, the caregiver returned (reunion). The test was repeated 10 times for each bird and video recorded in order to analyze their behaviour. The data show significantly higher crown and nape feather heights, higher redness of the skin and higher frequency of contact-seeking behaviours during the union and reunion phases than during the separation phase during which they expressed long distance contact calls. We observed the expression of eye pinning during the union and reunion phases in one out of five macaws. We argue that variation in facial displays provides indicators of parrot's positive appraisal of the caretaker presence. Our results broaden the scope for further studies on parrots' expression of their subjective feelings.

Impact of natural and artificial prenatal stimulation on the behavioural profile of Japanese quail.

As the sensory systems of vertebrates develop prenatally, embryos perceive many environmental stimuli that can influence the ontogeny of their behaviour. Whether the nature and intensity of prenatal stimuli affect this ontogeny differently remains to be investigated. In this context, this study aimed to analyse the effects of prenatal auditory stimulation (natural stimulation, NS; predator vocalisations or artificial stimulation, AS; metallic sounds) on the subsequent behaviour of young Japanese quail (Coturnix coturnix japonica). For this, behavioural variables recorded during ethological tests evaluating emotional and social reactivity were analysed using a principal component analysis. This analysis revealed significant differences between the behavioural profile of stimulated chicks and that of non-exposed chicks. Indeed, chicks exposed to NS expressed more intense emotional responses in fearful situations, but less neophobia when exposed to a novel environment or object, whereas chicks exposed to AS appeared more sensitive to social isolation. Our results show that the acoustic environment of embryos can influence the way young birds subsequently interact with their social and physical environment after hatching, and face challenges in changing living conditions.

Generation of the induced pluripotent stem cell line UHOMi002-A from peripheral blood mononuclear cells of a healthy male donor.

Human pluripotent stem cells (hiPSC) are highly valuable tools to model lung development and chronic bronchial diseases. We generated a hiPSC line from a highly characterized 40-year-old healthy male nonsmoking donor. Peripheral blood mononuclear cells (PBMCs) were reprogrammed using integration-free Sendai Virus. The cell line had normal karyotype, expressed pluripotency hallmarks, and differentiated into the three primary germ layers. The reported UHOMi002-A iPSC line may be used as a control to model lung development, study human chronic bronchial diseases and drug testing.

Horses Could Perceive Riding Differently Depending on the Way They Express Poor Welfare in the Stable.

This study investigated the relationships between four behavioral and postural indicators of a compromised welfare state in loose boxes (stereotypies, aggressive behaviors toward humans, withdrawn posture reflecting unresponsiveness to the environment, and alert posture indicating hypervigilance) and the way horses perceived riding. This perception was inferred using a survey completed by the usual riding instructor and during a standardized riding session (assessment of behaviors and postures, qualitative behavior assessment (QBA) and characterization of the horses' locomotion using an inertial measurement unit). In accordance with ear and tail positions and the QBA, stereotypic and the most hypervigilant horses in loose boxes seemed to experience a more negative affective state during the riding session compared with nonstereotypic and less hypervigilant animals (P < .02 in all cases). Horses which were aggressive toward humans in loose boxes had higher scores regarding the occurrence of discomfort and defensive behaviors on the survey than nonaggressive horses (P = .03). They also presented higher dorsoventral accelerations at a canter during the riding session (P = .03), requiring the rider to increase his spinal movement (P = .005). These results suggest that aggressive horses may be harder to ride than nonaggressive animals. The expression of unresponsiveness to the environment in loose boxes was related to more reluctance to move forward, as assessed in the survey (P = .006). This study suggests that a compromised welfare state in the stable is related to horses having a more negative perception of riding. This perception could vary depending on the expression of poor welfare.

Bill covering and nape feather ruffling as indicators of calm states in the Sulphur-crested cockatoo (Cacatua galerita).

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.

Human behaviour at the origin of maternal effects on offspring behaviour in laying hens (Gallus gallus domesticus).

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.

Generation of the induced pluripotent stem cell line UHOMi001-A from a patient with mutations in CCDC40 gene causing Primary Ciliary Dyskinesia (PCD).

Primary Ciliary Dyskinesia (PCD) is a rare heterogeneous genetic disorder affecting motile cilia structure and function leading to lung disease. We generated induced pluripotent stem cells (iPSCs) from dermal fibroblasts of a female PCD patient carrying disease-causing variants in the CCDC40 gene. Reprogramming was performed with the human OSKM transcription factors using the Sendai-virus delivery system. The resulting transgene free iPSCs had normal karyotype, expressed pluripotency markers, could differentiate into the three germ layers in vivo and retained the disease-causing CCDC40 mutations. This iPSC line could be useful to model PCD disease and test gene therapy strategies. Resource Table.

Facial display and blushing: Means of visual communication in blue-and-yellow macaws (Ara Ararauna)?

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 naïve 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.

Are there facial indicators of positive emotions in birds? A first exploration in Japanese quail.

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.

Emotional state and personality influence cognitive flexibility in horses (Equus caballus).

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 (E°). 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 E° 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

Incubation temperature affects the expression of young precocial birds' fear-related behaviours and neuroendocrine correlates.

The influence of embryonic microclimate on the behavioural development of birds remains unexplored. In this study, we experimentally tested whether chronic exposure to suboptimal temperatures engendered plasticity in the expression of fear-related behaviours and in the expression of the corticotropin-releasing factor in the brains of domestic chicks (Gallus g. domesticus). We compared the neurobehavioural phenotypes of a control group of chicks incubated in an optimal thermal environment (37.8 °C) with those of a group of experimental chicks exposed chronically in ovo to suboptimal temperatures (27.2 °C for 1 hour twice a day). Chronic exposure to a suboptimal temperature delayed hatching and decreased growth rate and experimental chicks had higher neophobic responses than controls in novel food and novel environment tests. In addition, experimental chicks showed higher expression of corticotropin-releasing factor than did controls in nuclei of the amygdala, a structure involved in the regulation of fear-related behaviours. In this study, we report the first evidence of the strong but underappreciated role of incubation microclimate on the development of birds' behaviour and its neurobiological correlates.

Accounting for linkage disequilibrium in genome scans for selection without individual genotypes: The local score approach.

Detecting genomic footprints of selection is an important step in the understanding of evolution. Accounting for linkage disequilibrium in genome scans increases detection power, but haplotype-based methods require individual genotypes and are not applicable on pool-sequenced samples. We propose to take advantage of the local score approach to account for linkage disequilibrium in genome scans for selection, cumulating (possibly small) signals from single markers over a genomic segment, to clearly pinpoint a selection signal. Using computer simulations, we demonstrate that this approach detects selection with higher power than several state-of-the-art single-marker, windowing or haplotype-based approaches. We illustrate this on two benchmark data sets including individual genotypes, for which we obtain similar results with the local score and one haplotype-based approach. Finally, we apply the local score approach to Pool-Seq data obtained from a divergent selection experiment on behaviour in quail and obtain precise and biologically coherent selection signals: while competing methods fail to highlight any clear selection signature, our method detects several regions involving genes known to act on social responsiveness or autistic traits. Although we focus here on the detection of positive selection from multiple population data, the local score approach is general and can be applied to other genome scans for selection or other genomewide analyses such as GWAS.

Lipids in maternal diet influence yolk hormone levels and post-hatch neophobia in the domestic chick.

We assessed whether the ratio of dietary n-6/n-3 polyunsaturated fatty acids (PUFA) during egg formation engenders transgenerational maternal effects in domestic chicks. We analyzed yolk lipid and hormone concentrations, and HPA-axis activity in hens fed a control diet (high n-6/n-3 ratio) or a diet enriched in n-3 PUFAs (low n-6/n-3 ratio) for 6 consecutive weeks. Their chicks were tested for neophobia during the first week of life. We found higher corticosterone metabolites in droppings of hens fed the diet enriched in n-3 and significantly higher concentrations of yolk progesterone, androstenedione, and estradiol in their eggs compared to controls. Chicks of hens fed the n-3 enriched diet showed a lower body mass at hatch than controls and expressed higher neophobia when exposed to a novel object. These results add support to the hypothesis that the nutritional state of female birds produces variation in yolk hormone levels and engender maternal effects.

Yolk hormones influence in ovo chemosensory learning, growth, and feeding behavior in domestic chicks.

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.

Artificially Increased Yolk Hormone Levels and Neophobia in Domestic Chicks.

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.

A medium density genetic map and QTL for behavioral and production traits in Japanese quail.

BACKGROUND: Behavioral traits such as sociability, emotional reactivity and aggressiveness are major factors in animal adaptation to breeding conditions. In order to investigate the genetic control of these traits as well as their relationships with production traits, a study was undertaken on a large second generation cross (F2) between two lines of Japanese Quail divergently selected on their social reinstatement behavior. All the birds were measured for several social behaviors (social reinstatement, response to social isolation, sexual motivation, aggression), behaviors measuring the emotional reactivity of the birds (reaction to an unknown object, tonic immobility reaction), and production traits (body weight and egg production). RESULTS: We report the results of the first genome-wide QTL detection based on a medium density SNP panel obtained from whole genome sequencing of a pool of individuals from each divergent line. A genetic map was constructed using 2145 markers among which 1479 could be positioned on 28 different linkage groups. The sex-averaged linkage map spanned a total of 3057 cM with an average marker spacing of 2.1 cM. With the exception of a few regions, the marker order was the same in Japanese Quail and the chicken, which confirmed a well conserved synteny between the two species. The linkage analyses performed using QTLMAP software revealed a total of 45 QTLs related either to behavioral (23) or production (22) traits. The most numerous QTLs (15) concerned social motivation traits. Interestingly, our results pinpointed putative pleiotropic regions which controlled emotional reactivity and body-weight of birds (on CJA5 and CJA8) or their social motivation and the onset of egg laying (on CJA19). CONCLUSION: This study identified several QTL regions for social and emotional behaviors in the Quail. Further research will be needed to refine the QTL and confirm or refute the role of candidate genes, which were suggested by bioinformatics analysis. It can be hoped that the identification of genes and polymorphisms related to behavioral traits in the quail will have further applications for other poultry species (especially the chicken) and will contribute to solving animal welfare issues in poultry production.

Short- and long-term effects of unpredictable repeated negative stimuli on Japanese quail's fear of humans.

Numerous aversive events occur in poultry production, and if repeated and unpredictable, can result in an impaired welfare. Some events such as handling can be perceived negatively and it is of interest to understand how humans' behaviour could affect poultry's behaviours and especially its avoidance of humans. Our aim was to evaluate short- and long-lasting effects of a 3-week procedure involving unpredictable repeated negative stimuli (URNS) applied during the post-juvenile period on quail's reactivity to humans. We compared the reactions of two sets of quail: URNS was applied to one set (treated quail) and the other set was left undisturbed (control quail). When two weeks old, treated quail were exposed to a variety of negative stimuli, either applied automatically or involving human presence. One and seven weeks after the termination of the procedure, the reactivity of control and treated quail to a passive human being was evaluated. Furthermore, the experimenter with her hand on a trough containing a mealworm assessed the propensity of quail of both groups to habituate to feed close to a human being. In the presence of a seated observer, treated quail were more inhibited and more alert than control quail. Likewise, seven weeks after the end of the URNS procedure, more treated than control quail adopted a fear posture. Moreover, whereas control quail spent as much time in the different areas of their cages, treated quail spent more time in the rear part of their cages. Finally, whereas control quail habituated gradually to feed near the experimenter's hand, treated quail did not. All these tests evidence negative short- and long-term effects on treated quail's reactivity to a passive human being and on their habituation to a human being when her presence is positively reinforced. This highlights the importance of young poultry's experience with humans in production.

Emotionality modulates the effect of chronic stress on feeding behaviour in birds.

Chronic stress is a long-lasting negative emotional state that induces negative consequences on animals' psycho-physiological state. This study aimed at assessing whether unpredictable and repeated negative stimuli (URNS) influence feeding behaviour in quail. Sixty-four quail were exposed to URNS from day 17 to 40, while 64 quail were undisturbed. Two lines divergently selected on their inherent emotionality were used to assess the effect of genetic factors on the sensitivity to URNS. All quail were submitted to a sequential feeding procedure (using two diets of different energetic values) which placed them in a contrasting situation. Behavioural tests were performed to assess the emotional reactivity of the two lines. Results confirmed that differences exist between them and that their emotional reactivity was enhanced by URNS. Diet preferences, motivation and daily intake were also measured. URNS did not change the preferences for the hypercaloric diet compared to the hypocaloric diet in choice tests, but they reduced daily intakes in both lines. Motivations for each diet were differently affected by URNS: they decreased the motivation to eat the hypercaloric diet in quail selected for their low inherent fearfulness whereas they increased the motivation to eat the hypocaloric diet in quail selected for their high inherent fearfulness, which suggested a devaluation process in the former and a compensatory behaviour in the later. Growth was furthermore reduced and laying delayed by URNS in both lines. In conclusion, the exposure to URNS induced interesting changes in feeding behaviour added with an increase in emotional reactivity and an alteration of production parameters. This confirms that both lines of quail experienced a chronic stress state. However differences in feed motivation and emotional reactivity between lines under chronic stress suggested that they experienced different emotional state and use different ways to cope with it depending on their genetic background.

Evidence of phenotypic and genetic relationships between sociality, emotional reactivity and production traits in Japanese quail.

The social behavior of animals, which is partially controlled by genetics, is one of the factors involved in their adaptation to large breeding groups. To understand better the relationships between different social behaviors, fear behaviors and production traits, we analyzed the phenotypic and genetic correlations of these traits in Japanese quail by a second generation crossing of two lines divergently selected for their social reinstatement behavior. Analyses of results for 900 individuals showed that the phenotypic correlations between behavioral traits were low with the exception of significant correlations between sexual behavior and aggressive pecks both at phenotypic (0.51) and genetic (0.90) levels. Significant positive genetic correlations were observed between emotional reactivity toward a novel object and sexual (0.89) or aggressive (0.63) behaviors. The other genetic correlations were observed mainly between behavioral and production traits. Thus, the level of emotional reactivity, estimated by the duration of tonic immobility, was positively correlated with weight at 17 and 65 days of age (0.76 and 0.79, respectively) and with delayed egg laying onset (0.74). In contrast, a higher level of social reinstatement behavior was associated with an earlier egg laying onset (-0.71). In addition, a strong sexual motivation was correlated with an earlier laying onset (-0.68) and a higher number of eggs laid (0.82). A low level of emotional reactivity toward a novel object and also a higher aggressive behavior were genetically correlated with a higher number of eggs laid (0.61 and 0.58, respectively). These results bring new insights into the complex determinism of social and emotional reactivity behaviors in birds and their relationships with production traits. Furthermore, they highlight the need to combine animal welfare and production traits in selection programs by taking into account traits of sociability and emotional reactivity.

Moderate heat challenge increased yolk steroid hormones and shaped offspring growth and behavior in chickens.

BACKGROUND: Environmental challenges might affect the maternal organism and indirectly affect the later ontogeny of the progeny. We investigated the cross-generation impact of a moderate heat challenge in chickens. We hypothesized that a warm temperature--within the thermotolerance range--would affect the hormonal environment provided to embryos by mothers, and in turn, affect the morphology and behavioral phenotype of offspring. METHODOLOGY/PRINCIPAL FINDINGS: Laying hens were raised under a standard thermal condition at 21°C (controls) or 30°C (experimental) for 5 consecutive weeks. A significant increase was observed in the internal temperature of hens exposed to the warm treatment; however plasma corticosterone levels remained unaffected. The laying rate was not affected, but experimental hens laid lighter eggs than the controls during the treatment. As expected, the maternal thermal environment affected yolk hormone contents. Eggs laid by the experimental hens showed significantly higher concentrations of yolk progesterone, testosterone, and estradiol. All chicks were raised under standard thermal conditions. The quality of hatchlings, growth, feeding behavior and emotional reactivity of chicks were analyzed. Offspring of experimental hens (C30 chicks) were lighter but obtained better morphological quality scores at hatching than the controls (C21 chicks). C30 chicks expressed lesser distress calls when exposed to a novel food. Unlike C21 chicks, C30 chicks expressed no preference for energetic food. CONCLUSION/SIGNIFICANCE: Our findings suggest that moderate heat challenge triggers maternal effects and modulate the developmental trajectory of offspring in a way that may be adaptive. This suggests that the impact of heat challenges on captive or wild populations might have a cross-generation effect.