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Despite the domestication of sheep and goats by humans for several millennia, we still lack comparative data on their cognitive capacity. Comparing the cognitive skills of farm animals can help understand the evolution of cognition. In this study, we compared the performances of sheep and goats in inference by exclusion tasks. We implemented two tasks, namely a cup task and a tube task, to identify whether success in solving the task could be attributed to either low-level mechanisms (avoiding the empty location strategy) or to deductive reasoning (if two possibilities A and B, but not A, then it must be B). In contrast to a previous study comparing goats and sheep in a cup task, we showed that both species solved the inferential condition with high success rates. In the tube task, performances could not be explained by alternative strategies such as avoiding the empty tube or preferring the bent tube. When applying a strict set of criteria concerning responses in all conditions and controlling for the potential effects of experience, we demonstrate that two individuals, a goat and a sheep, fulfil these criteria. This suggests that sheep and goats are able to make inferences based on deductive reasoning.

International audience; The psychoendocrine evaluation of lamb development has demonstrated that maternal deprivation and milk replacement alters health, behavior and endocrine profiles. While lambs are able to discriminate familiar and non-familiar conspecifics (mother or lamb), only lambs reared with their mother develop such clear social discrimination or preference. Lambs reared without mother display no preference for a specific lamb from its own group. Differences in exploratory and emotional behaviours between mother-reared and mother deprived lambs have also been reported. As these behavioural abilities are supported by the brain, we hypothesize that rearing with maternal deprivation and milk replacement leads to altered brain development and maturation. To test this hypothesis, we examined brain morphometric and microstructural variables extracted from in-vivo T1-weighted and diffusion-weighted magnetic resonance images acquired longitudinally (1 week, 1.5 months and 4.5 months of age) in mother-reared and mother-deprived lambs. From the morphometric variables the caudate nuclei volume was found to be smaller for mother-deprived than for mother-reared lambs. T1-weighted signal intensity and radial diffusivity were higher for mother-deprived than for mother-reared lambs in both the white and gray matters. The fractional anisotropy of the white matter was lower for mother-deprived than for mother-reared lambs. Based on these morphometric and microstructural characteristics we conclude that maternal deprivation delays and affects lamb brain growth and maturation.

International audience; This study aimed to characterize inappropriate maternal behaviours in stabled dromedary camels in order to detect the main causes of calf rejection, and to develop a suitable method to remediate mismothering. A herd of 45 pregnant females was under video surveillance to detect periparturient females. Twelve pregnant dromedary females (6 accepting their newborns and 6 rejecting them 1 h after calving) were selected as experimental subjects. A blood sample was collected during calving to determine cortisol levels. Maternal behaviour at the calving site was assessed during the first hour postpartum. Rejecting dams and their neonates were moved into a confinement enclosure to assess their maternal behaviour over a period of 30 min at 1 h, 6 h, 12 h, 24 h, 48 h, 72 h during confinement and at 7 d postpartum. Five IU of synthetic oxytocin were injected at 8:00, 12:00 and 16:00 to induce milk ejection in rejecting dams and one qualified person collected colostrum. The newborns were fed by holding the bottle of colostrum on the surface of the mother's udder and keeping body contact between the two animals. Results showed that the duration of parturition was longer in the mothers that rejected their calves (P = 0.04). Such females spent more time in standing position during the calving process (P = 0.01) compared to accepting mothers, had higher plasma cortisol levels (P < 0.01), and gave birth preferentially while standing. Rejecting mothers changed calving sites and displayed head-turning more frequently (P < 0.01 in both parameters) than accepting mothers. Two causes of rejection were identified: dystocia and presence of an alien calf at the birth site. Moreover, a female showed a case of repeated rejecters. During the first hour postpartum, rejecting mothers failed to express good maternal care and moved away from their neonates. In the confinement enclosure, they exhibited attack behaviour toward their calves, displayed low sniffing activity, and emitted mainly high-pitched grunt. Aggression diminished progressively and disappeared (P < 0.0001) on the 2nd day of confinement while sniffing behaviour increased steadily (P = 0.001). The number of high-pitched grunt decreased over time while the number of low-pitched grunt increased over the first 3 days before declining significantly at the end of the confinement period (P < 0.0001). In conclusion, rejecting mothers can be very aggressive towards their own newborns. However, three days of confinement and forced contact with the calf while bottle-feeding it with the mother's milk was sufficient to alleviate mismothering in dromedaries and establish proper mother-young relationships.

International audience; Currently, a trend toward the commercialization of dromedary milk associated with recent intensive rearing systemshas startingworldwide which impose constraints on animals affecting their behavioral repertoiresandwelfare status. The aimof this study was to investigate the effects of damparity and calf sex on parturition, neonatal, and maternal behaviors in stabled Maghrebi dairy camels (Camelus dromedarius). Thirty-six (primiparas N= 10; multiparas N= 26) periparturient femaleswere kept under video surveillance using a digital IR camera and 24-h sessionswere chosen to assess calving, maternal, and neonatal behaviors in calving pens. Duration of restlessness, process of giving birth, and expulsion of fetal membranes were assessed. After first suckling, dams and their calves were moved into an individual enclosure to assess maternal behavior at 12 h, 24 h, 48 h, 72 h, and 7d postpartum. Behaviorwas assessed using a camcorder for 30min after 1 h of young separation in an adjacent enclosure. Results showed an effect of parity on the duration of the birth process which was longer for primiparous thanmultiparous camels (P= 0.034). During this stage, primiparous females tended to raise their tails more often (P= 0.054) and spentmore time standing (P= 0.001) than multiparous camels. Neonatal behaviorwas affected by calf sex. Female newborns took less time to raise their heads (P= 0.041) andtostandup(P= 0.048) for the first time and were the earliest to suckle their dams (P= 0.032). Multiparous dams stood up sooner (P= 0.019) after calving and suckled their calves earlier (P= 0.043) than primiparous dams. They emittedmore bleats and exhibitedmore sniffing during the firstweek postpartumthan primiparas. During the first postpartumweek, both primiparas and multiparas showed a decrease in the total number of bleats (P < 0.001), low-pitch bleats (P < 0.001), and high-pitch bleats (P< 0.001), in sniffing frequency (P< 0.001) and sniffing duration (P < 0.001). This is the first study to describe in detail the calving, maternal, and neonatal behaviors of dromedary camels and to show the influence of parity and calf sex. Maternal care toward the newborn calf exhibited by a high level of bleating and sniffing activities in the first 2 days suggest that they play an important role in the establishment ofmother-young relationship. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of The Animal Consortium.

International audience; The common practice of artificially rearing lambs from prolific meat breeds of sheep constitutes a welfare issue due to increased mortality rates and negative health issues. In this multidisciplinary study, we investigated the possible short- and mid-term advantages of artificially feeding fresh ewe's milk instead of commercial milk replacer on lambs' growth, health and welfare. Romane lambs were either separated from their mothers on D3 and fed with Lacaune ewes' milk (LAC, n = 13) or milk replacer (REP, n = 15), or they were reared by their mothers (MOT, n = 15). On D45, they were weaned, gathered in single-sex groups until the end of the study on D150. Lamb performance and biomarkers of overall health were assessed by measuring: growth, dirtiness of the perianal area, enteric pathogens in the faeces, total antioxidant status and redox status assessed by plasma reduced glutathione/oxidised glutathione ratio, and immune response after vaccination against chlamydiosis. As an exploratory approach, blood cell transcriptomic profiles were also investigated. Last, qualitative behaviour assessment (QBA) was performed as an integrated welfare criterion. Lacaune ewes' milk and REP never differed in their average daily gain but grew less than MOT lambs in the early suckling period and just after weaning. No effect was detected afterwards. On D30, LAC and REP lambs had lower total antioxidant and higher redox status than MOT lambs but did not differ among themselves. Lacaune ewes' milk and MOT had a cleaner perianal area than REP lambs on D21, while faecal pathogen infection did not vary between the treatment groups. After vaccination, LAC also had a stronger immune response on D90 compared to REP lambs. Transcriptome analysis performed on D150 showed differential gene expression, mainly in relation to inflammatory, immune and cell cycle response, between male lambs of the LAC group and those of the MOT and REP groups. Based on QBA, LAC lambs never differed from MOT lambs in their general activity and varied from REP only on D21; REP lambs were always more agitated than MOT lambs. In conclusion, artificial milk feeding impaired early growth rate, health and emotional state mainly during the milk feeding period and at weaning. Feeding artificially reared lambs with fresh ewe's milk partly mitigated some of the negative effects induced by milk replacer but without achieving the full benefit of being reared by the mother. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of The Animal Consortium.

Chez les mammifères, la séparation maternelle à la naissance induit un stress chronique avec pour conséquences des altérations comportementales et neurobiologiques. Ainsi, en élevage ovin, les agneaux surnuméraires sont séparés de leur mère à la naissance et nourris avec des laits artificiels, induisant de telles altérations. Des études montrent l’importance du microbiote intestinal sur le développement comportemental. Notre hypothèse est qu’une alimentation enrichie en prébiotique dès la naissance contribuerait, via une action sur le microbiote, à prévenir certains des désordres associés au stress de séparation maternelle, en particulier comportementaux.Des agnelles ont reçu le colostrum de leur mère les 2 jours suivant la naissance avant d’être séparées et nourries avec un lait commercial dépourvu (Preb-) ou enrichi avec un prébiotique (Preb+, 1% galactofructose) jusqu’au sevrage à 7 semaines. Après le sevrage, les agnelles ont toutes reçu une nourriture standard d’élevage. La maturation du microbiote fécal des agnelles a été suivie par séquençage de la région V3-V4 du gène codant l’ARNs 16S à l’âge de 3, 7 et 10 semaines. Parallèlement, leur comportement social a été comparé par une approche éthologique. La position des individus et leurs activités au sein du groupe ont été quantifiées toutes les 10 minutes pendant 3 heures par jour ainsi que les interactions affiliatives et agonistiques, et les vocalisations.Sur la période durant laquelle le galactofructose est apporté par le lait, une restructuration de la composition du microbiote révélant les propriétés bifidogènes du prébiotique est observée : la sur-implantation précoce de 3 espèces de Bifidobactéries au détriment de nombreuses communautés appartenant aux Clostridiales se traduit par une moindre richesse d’espèces dans le groupe Preb+. Elles présentent parallèlement sur le plan comportemental des indices d’association significativement plus importants et des interactions affiliatives plus fréquentes. Elles ont également tendance à manifester moins d’interactions agonistiques et à moins vocaliser. Enfin, les agnelles Preb+ consacrent davantage de temps à consommer du lait sans que ce comportement n’affecte leur croissance.Après le sevrage, une empreinte spécifique du microbiote des agnelles Preb+ est conservée et se caractérise par un meilleur équilibre de l’abondance des espèces présentes, avec notamment, une abondance augmentée des Clostridiales et une meilleure colonisation par Akkermansia muciniphila. Si les différences de comportement social s’estompent après le sevrage, en revanche les agnelles Preb+ présentent un réseau social plus structuré. Enfin, l’intégration de ces données à celles du microbiote par des analyses multidimensionnelles révèle des covariations significatives, mettant ainsi en exergue de potentielles relations entre les modulations du microbiote intestinal et le comportement social lors du développement.En conclusion, l’apport précoce de galactofructose dans le lait diminue durablement les troubles du comportement social des agnelles soumises à un allaitement artificiel et l’absence maternelle. Cette étude suggère que ce prébiotique, via ses répercussions sur la maturation du microbiote intestinal, pourrait compenser certains des effets délétères associés aux stress précoces.

International audience; Although sheep are known to be seasonal breeders and give birth in winter, not all of them follow this trend. A few breeds can be mated and give birth all year round, meaning that mothers and neonates will have to face contrasting climatic conditions. The aim of this study was to test whether lambing season affects maternal and neonatal behaviors in D’man sheep. During four different lambing seasons (winter, autumn, summer, spring), periparturient ewes (n = 111) and their lambs (n = 213) were kept under 24-h-video surveillance in order to record post-partum behaviors. Mother-young preference was tested around 48 h after parturition. Lamb vigor was studied by the determination of birth weight, early postnatal behavior and rectal temperature at birth and 48 h later. Litter expulsion time was not affected by lambing season but birth weight was biased against summer and winter born lambs. Ewes provided a higher intensity of care to their offspring in winter: latency for grooming was shorter and time spent grooming was longer compared to lambing in spring and summer (P = 0.01 in all cases). On the other hand, lambs were the most active in spring as they were faster to extend their hind legs (P = 0.01), stand up (P = 0.04) and reach the udder (P = 0.04). Rectal temperature at 48 h was affected by season of birth (P < 0.001) with higher values observed in summer. Glycaemia variation between birth and 48 h was the lowest in spring born lambs and plasma levels increased less in spring born lambs than in winter (P < 0.0001), autumn (P < 0.0001) and summer born lambs (P < 0.0001). In the choice test, mothers clearly preferred their own young and no season effect was detected except that in the first minute of the test they spent less time near their own young in winter than in the other seasons (P = 0.04). Lambs also chose their mother successfully without any major effect of the season however, but winter born lambs were the least vocal (P = 0.01). Overall, this study show that maternal care, lamb behavior and vigor vary lightly according to seasons, albeit not in a consistent manner. In conclusion, a season is no more detrimental than another for the onset of mother-young relationships. Keywords: parturition, maternal behavior, neonate behavior, bonding, glycaemia

International audience; A key question in the field of animal cognition is how animals comprehend their physical world. Object permanence is one of the fundamental features of physical cognition. It is the ability to reason about hidden objects and to mentally reconstruct their invisible displacements. This cognitive skill has been studied in a wide range of species but never directly in the horse (Equus caballus). In this study, we therefore assessed the understanding of visible and invisible displacements in adult Welsh mares in two complementary experiments, using different horses. In experiment 1, visible displacement was investigated using two tasks adapted from the Uzgiris and Hunt scale 1. Invisible displacement was assessed using a transposition task, in which food was first hidden in one of two containers and the location of the containers was then switched. In experiment 2, we further investigated horses' understanding of visible and invisible displacements using an easier procedure designed to avoid potentially confounding factors. In both experiments, horses successfully completed the tasks involving visible displacement with two or three possible hiding places. However, in both experiments, horses failed the transposition tasks, suggesting that they may not be able to track the displacement of an object that is not directly perceived (i.e., invisible displacement). These results bring new insights into object permanence in horses and how they represent their physical world.

International audience; Social animals can gain important benefits by inferring the goals behind the behavior of others. However, this ability has only been investigated in a handful of species outside of primates. In this study, we tested for the first time whether domestic horses can interpret human actions as goal directed. We used the classical "unwilling versus unable" paradigm: an experimenter performed three similar actions that have the same outcome, but the goal of the experimenter differed. In the unwilling condition, the experimenter had no intention to give a piece of food to a horse and moved it out of reach when the horse tried to eat it. In the two unable conditions, the experimenter had the intention to give the food to the horse but was unable to do so, either because there was a physical barrier between them or because of the experimenter's clumsiness. The horses (n = 21) reacted differently in the three conditions: they showed more interest in the unable conditions, especially in the unable clumsy condition, than in the unwilling condition. These results are similar to results found in primates with the same paradigm and suggest that horses might have taken the experimenter's goal, or even intentions, into account to adapt their behavior. Hence, our study offers more insights into horse interspecific social cognition towards humans.

International audience; Animals can indirectly gather meaningful information about other individuals by eavesdropping on their third-party interactions. In particular, eavesdropping can be used to indirectly attribute a negative or positive valence to an individual and to adjust one's future behavior towards that individual. Few studies have focused on this ability in nonhuman animals, especially in nonprimate species. Here, we investigated this ability for the first time in domestic horses (Equus caballus) by projecting videos of positive and negative interactions between an unknown human experimenter (a "positive" experimenter or a "nega-tive" experimenter) and an actor horse. The horses reacted emotionally while watching the videos, expressing behavioral (facial expressions and contact-seeking behavior) and physiological (heart rate) cues of positive emotions while watching the positive video and of negative emotions while watching the negative video. This result shows that the horses perceived the content of the videos and suggests an emotional contagion between the actor horse and the subjects. After the videos were projected, the horses took a choice test, facing the positive and negative experimenters in real life. The horses successfully used the interactions seen in the videos to discriminate between the experimenters. They touched the negative experimenter significantly more, which seems counterintuitive but can be interpreted as an appeasement attempt, based on the existing literature. This result suggests that horses can indirectly attribute a valence to a human experimenter by eavesdropping on a previous third-party interaction with a conspecific.

International audience; The present study examined in lambs whether exposure to flavors derived from pregnant mother‘s diet and transferred to amniotic fluid (AF) could induce a preference for artificial milk containing one of these flavors. To test this hypothesis, cumin was added to the maternal diet in the last month of gestation. Preference for artificial milk containing p-cymene, one of the chemosensory compounds of cumin, was tested within the first two days after birth in maternally deprived lambs born from mothers fed a cumin-flavored diet (Cumin group), or an unflavored diet (Control group). Aromatic profile of AF from cumin-fed mothers was analyzed by GC-MS/MS to determine whether p-cymene could be detected. While the control group avoided the flavored artificial milk on day 1, the Cumin group did not and showed a preference for the cumin-scented formula on day 2. GC-MS/MS profile of AF revealed that four of the main volatile cumin compounds, p-cymene, p-cymenene, β-pinene and γ-terpinene were present in variable amounts in all samples, p-cymene being the most frequently detected. These findings indicate that newborn lambs can memorize flavors from the mother's diet present in AF and that prenatal experience influences their preference for an artificial milk containing one specific flavor.

International audience; The removal of pre-existing geographical barriers between species, notably by humans, allows previously isolated species to hybridize. Interspecies hybridization has been studied at different levels but the mother-young relationship, which is crucial for the offspring's survival, has not been investigated in large wild mammals. We compared the establishment of the mother-young relationship at birth and during the first week of life and the morphological development of the young in red deer, Cervus elaphus, sika deer, Cervus nippon, and their hybrids (male nippon x female elaphus). Most mother-young behaviours did not differ between the three groups, showing strong conservation of peripartum behaviours in cervids. In contrast, the behaviour and body size of the hybrid young were similar or tended to be close to those found in the maternal species, suggesting important maternal effects. In addition, hybrid young were more likely to be standing during the first week than young from the other groups, possibly resulting from increased maternal stimulation and/or hybrid vigour. Adult females in the herd were more likely to perform smell-related and agonistic behaviours towards the hybrid young, suggesting potential species recognition issues, which require further investigation. In conclusion, our findings show that hybridization has no noticeable impact on the mother-young relationship, which could partly explain the success of hybridization between the sika and red deer in the wild. (C) 2019 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

International audience; Simple Summary: Recently, an increasing number of studies have investigated the expression and perception of emotions by non-human animals. In particular, it is of interest to determine whether animals can link emotion stimuli of different modalities (e.g., visual and oral) based on the emotions that are expressed (i.e., to recognize emotions cross-modally). For domestic species that share a close relationship with humans, we might even wonder whether this ability extends to human emotions. Here, we investigated whether domestic horses recognize human emotions cross-modally. We simultaneously presented two animated pictures of human facial expressions, one typical of joy and the other of anger; simultaneously, a speaker played a human non-verbal vocalization expressing joy or anger. Horses looked at the picture that did not match the emotion of the vocalization more (probably because they were intrigued by the paradoxical combination). Moreover, their behavior and heart rate differed depending on the vocalization: they reacted more negatively to the anger vocalization and more positively to the joy vocalization. These results suggest that horses can match visual and vocal cues for the same emotion and can perceive the emotional valence of human non-verbal vocalizations. Abstract: Over the last few years, an increasing number of studies have aimed to gain more insight into the field of animal emotions. In particular, it is of interest to determine whether animals can cross-modally categorize the emotions of others. For domestic animals that share a close relationship with humans, we might wonder whether this cross-modal recognition of emotions extends to humans, as well. In this study, we tested whether horses could recognize human emotions and attribute the emotional valence of visual (facial expression) and vocal (non-verbal vocalization) stimuli to the same perceptual category. Two animated pictures of different facial expressions (anger and joy) were simultaneously presented to the horses, while a speaker played an emotional human non-verbal vocalization matching one of the two facial expressions. Horses looked at the picture that was incongruent with the vocalization more, probably because they were intrigued by the paradoxical combination. Moreover, horses reacted in accordance with the valence of the vocalization, both behaviorally and physiologically (heart rate). These results show that horses can cross-modally recognize human emotions and react emotionally to the emotional states of humans, assessed by non-verbal vocalizations.

The effect of prolificacy on mother-young mutual recognition is still largely unknown in sheep. The aim of the present study was to investigate the ability of prolific ewes to develop an exclusive bond with their neonate and to recognize each other from alien subjects. Observations were performed on 11 D'man and 16 Romanov ewes with, respectively, 19 and 37 of their lambs. Maternal selectivity was tested at 24 h postpartum during two consecutive periods of 3 min. All mothers accepted their own lambs at suckling, while 21 out of 27 (78%) rejected the alien, thus displaying mostly selective nursing. To assess mother-young recognition, a two-choice test was performed at 36 h postpartum. Ewes clearly preferred their own lambs to an alien lamb and behavioral differences were not found between mothers of small (singletons and twins) and large litters (triplets and quadruplets). Romanov ewes reached their own lambsmore rapidly and spent more time near them than D'man ewes. Lambs from small litters, in particular light lambs, clearly preferred their mothers to an alien dam; however, both light and heavy lambs in large litters did not discriminate between the two stimulus ewes. D'man lambs clearly preferred their mothers to an alien dam; in contrast, such a preference was not as clearly demonstrated in Romanov lambs.

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.

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International audience; Ewes develop a strong selective bond with their offspring, which is set immediately after lambing and maintained until weaning, which in domestic sheep occurs when lambs are 4-5 months old. However, in productive systems lambs are weaned earlier, when they are 2-5 months old. The aim of this experiment was to determine how long the preference for the mother is maintained after abrupt weaning in lambs that have been nursed by their dam for 3 months. Eighty-two single Corriedale lambs stayed with their mother until weaning at 3 months of age, when they were abruptly separated from their mothers and moved to another paddock located 1500 m away, avoiding any mother-young communication. Preference for the mother was tested using a two-choice test between their own and another mother from the same flock, matched for age and physiological status. Lambs were tested in a 10 m x 10 m x 7 m triangular testing enclosure with one ewe placed in each of the two holding pens. A wire mesh plastic fence prevented lambs from approaching the ewes at less than 1 m. A proximity zone near the ewes was defined (1 x 2 m). The location of the mother and the familiar ewe in the holding pens was alternated between tests. During 3 min were recorded: the proximity zone reached first, the latencies to enter each proximity zone, the total time spent in each proximity zone, and the number of bleats produced by the lamb while it was in each zone. All the lambs were tested 3 days before weaning, and 30 (n = 25), 40 (n = 15) or 60 days (n = 42) after weaning. Before weaning, there were no difference in the first proximity zone entered, but in the other variables lambs showed a strong preference for their mother rather than for the familiar ewe. Lambs still preferred their mother 30 days after weaning, although this preference was weakened. However, lambs tested 40 and 60 days after weaning did not show any preference. We concluded that after being weaned at three months of age, the preference of lambs for their mother in comparison to a familiar ewe decreases within 30 days, and finally disappeared 60 days after weaning.

Remerciements : Plateforme Phénotypage-Endocrinologie, INRA, UMR PRC 0085, Centre Tours Val de Loire; International audience; Characteristics of attachment were assessed in peer- and object-reared lambs, and compared to mothered subjects by taking into consideration distress, proximity seeking, and exploration during two separation-reunion tests in both the familiar and a novel environment. Plasma cortisol and oxytocin were assayed as physiological indicators of stress and being comforted during the separation-reunion test. Rewarding properties of the familiar figures were also determined in a conditioned place preference-like paradigm. Between-group analysis revealed the existence of secure attachment with the mother, alteration of secure attachment with the peer and weaker attachment with the object. Weaker attachment was expressed by a lack of distress during separation in the home pen and no preference for the place conditioned with the familiar object. Elevated basal plasma oxytocin levels, but not cortisol, observed in maternally deprived lambs were more likely linked to the absence of a maternal figure rather than social comfort during reunion.

Consequences of prenatal stress on emotional reactivity and cognitive abilities in offspring are under-documented in precocial mammals. Here, we investigated to what extent emotional reactivity, judgment bias and spatial learning abilities of lambs are affected by chronic stress during late pregnancy and by their dams' emotional reactivity. The 20 highest-responsive (HR) and 20 lowest-responsive (LR) ewes from a population of 120 Romane ewes were selected according to their pre-mating reactivity to social isolation in a new environment. Over the final third of pregnancy, 10 HR ewes and 10 LR ewes were exposed daily to various unpredictable aversive events such as restraint, mixing groups and transport while the other 20 selected ewes were not. In a human and an object test, prenatally-stressed lambs were more fearful than control lambs, but the prenatal stress effect was moderated by the reactivity of the mothers: prenatally-stressed lambs from ewes with high emotional reactivity were more affected. Prenatally-stressed lambs did not perform as well as control lambs in a maze test and showed pessimistic-like judgment in a cognitive bias test. Prenatally-stressed lambs were thus characterized by a negative affective state with increased fear reactions and impaired cognitive evaluation. The development of negative moods could have long-lasting consequences on the coping strategies of the lambs in response to their rearing conditions.

Impact of early rearing experience on brain development in sheep infant. . New animal models to understand the brain

The well-being of mammals kept in the laboratory or on the farm is a major concern worldwide. Having multiple and reliable indicators that appraise mammals living under assorted conditions is, therefore, essential to attain their well-being in captivity. This also constitutes a research topic in Behavioral Neuroendocrinology as the best indicators of an animal's welfare state are largely neuroendocrine and behavioral. In this chapter we selected species commonly found in laboratories or farms (rodents, rabbits, sheep, goats, bovines) to illustrate the effects of housing and environmental conditions, management practices, and early rearing on specific hormonal, behavioral, and immunological parameters.

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While behavioral mechanisms of bonding between young mammals and humans have been explored, brain structures involved in the establishment of such processes are still unknown. The aim of the study was to identify brain regions activated by the presence of the caregiver. Since human positive interaction plays an important role in the bonding process, activation of specific brain structures by stroking was also examined. Twenty-four female lambs reared in groups of three were fed and stroked daily by a female caregiver between birth and 5–7 weeks of age. At 4 weeks, an isolation-reunion-separation test and a choice test revealed that lambs developed a strong bond with their caregiver. At 5–7 weeks of age, lambs were socially isolated for 90 min. They either remained isolated or met their caregiver who stroked them, or not, at regular intervals over a 90-min period. Neuronal activation was investigated at the end of the period for maximum c-Fos expression. Reunion with the caregiver appeased similarly the lambs whether stroking was provided or not. Stroking did not activate a specific brain network compared to no stroking. In both cases, brain regions associated with olfactory, visual and tactile cue processing were activated in the presence of the caregiver, suggesting a multisensory process involved. In addition, activation of the oxytocinergic system in the hypothalamic paraventricular nucleus induced by the presence of the caregiver suggests similar neuroendocrine mechanisms involved in inter-conspecific and animal-human bonding.

This review is based on an invited presentation at the 65th Annual Meeting of the European Association for Animal Production held in Copenhagen, Denmark, August 2014; Neonatal mortality in small ruminant livestock has remained stubbornly unchanging over the past 40 years, and represents a significant loss of farm income, contributes to wastage and affects animal welfare. Scientific knowledge about the biology of neonatal adaptation after birth has been accumulating but does not appear to have had an impact in improving survival. In this paper, we ask what might be the reasons for the lack of impact of the scientific studies of lamb and kid mortality, and suggest strategies to move forward. Biologically, it is clear that achieving a good intake of colostrum, as soon as possible after birth, is crucial for neonatal survival. This provides fuel for thermoregulation, passive immunological protection and is involved in the development of attachment between the ewe and lamb. The behaviour of the lamb in finding the udder and sucking rapidly after birth is a key component in ensuring sufficient colostrum is ingested. In experimental studies, the main risk factors for lamb mortality are low birthweight, particularly owing to poor maternal nutrition during gestation, birth difficulty, litter size and genetics, which can all be partly attributed to their effect on the speed with which the lamb reaches the udder and sucks. Similarly, on commercial farms, low birthweight and issues with sucking were identified as important contributors to mortality. In epidemiological studies, management factors such as providing assistance with difficult births, were found to be more important than risk factors associated with housing. Social science studies suggest that farmers generally have a positive attitude to improving neonatal mortality but may differ in beliefs about how this can be achieved, with some farmers believing they had no control over early lamb mortality. Facilitative approaches, where farmers and advisors work together to develop neonatal survival strategies, have been shown to be effective in achieving management goals, such as optimising ewe nutrition, that lead to reductions in lamb mortality. We conclude that scientific research is providing useful information on the biology underpinning neonatal survival, such as optimal birthweights, lamb vigour and understanding the importance of sufficient colostrum intake, but the transfer of that knowledge would benefit from an improved understanding of the psychology of management change on farm. Developing tailored solutions, on the basis of adequate farm records, that make use of the now substantial body of scientific literature on neonatal mortality will help to achieve lower neonatal mortality.

Les ovins sont bien connus pour développer différentes formes d’attachement social. Le déclenchement de la motivation maternelle et le développement d’un lien mutuel entre la mère et son jeune sont sous l’influence combinée de stimulations hormonales et somato-sensorielles périphériques. Ces stimulations sont fournies par la parturition chez la mère et par les premiers épisodes de tétée chez le nouveau-né. Des changements neurophysiologiques profonds sont observés dans les bulbes olfactifs principaux de la brebis, alors qu’ils sont exposés à des odeurs d’agneau nouveau-né. L’activation de l’hypothalamus consécutive à la mise bas contribue à l’expression de la motivation maternelle et à la mémorisation des odeurs de l’agneau. L’hypothalamus et l’amygdale sont également activés chez le nouveau-né suite à l’ingestion de colostrum. L’ocytocine, un neuropeptide connu pour jouer un rôle clé dans les comportements prosociaux, facilite la construction de la relation mère-jeune. Lorsque des agneaux nouveau-nés sont séparés de leur mère pour être artificiellement nourris, une pratique agricole très commune, ils sont profondément affectés. Les réponses neuroendocrinologiques suggèrent que les agneaux sont dans une situation de détresse. Cependant, si un humain prend soin d’eux, une liaison interspécifique se met en place, facilitée par des contacts sociaux positifs dans lesquels l’allaitement au biberon ou les caresses jouent un rôle clé. De tels contacts activent le système ocytocinergique, comme cela est observé dans la construction du lien mère-jeune. Ainsi, dans des conditions d’élevage artificiel, l’être humain devient une figure d’attachement saillante qui se substitue à la mère et qui peut faciliter la gestion des agneaux., The sheep is well known to develop various forms of social attachment. The onset of maternal responsiveness and the development of the mutual mother-young bond are under the combined influence of hormonal and peripheral somatosensory stimulations. These stimuli are provided by parturition in the mother and by the first suckling episodes in the neonate. Following parturition, the main olfactory bulbs of the ewe undergo profound neurophysiological changes when exposed to offspring odours while activations in the hypothalamus contribute to maternal responsiveness and memorization of lamb odours. Similarly, in the neonate the hypothalamus and the amygdala respond to colostrum ingestion. Oxytocin, a neuropeptide known to play a key role in prosocial behaviours, facilitates mother-young bonding. When new-born lambs are separated from their mother to be artificially-fed, a very common farm practice, they are profoundly affected. Neuroendocrine responses suggest that lambs are in a situation of distress. However, should a human caregiver look after them, an interspecific bond is then facilitated by positive social contacts including bottle-feeding or stroking. These contacts activate the oxytocinergic system, like in the mother-young bonding process. Thus, under artificial rearing conditions,the human becomes a salient attachment figure who may facilitate the management of lambs on farms.

The aim of this work was to assess maternal and neonatal changes in plasma proteins, glucose and cortisol and to quantify the colostral immunoglobulin G (IgG) transfer in the peri-partum period in D'man sheep, a prolific breed, taking into account the parity of the ewe. The concentrations of proteins and glucose were high in the ewes on day 7 and at lambing before decreasing. Likewise, cortisol plasma concentration was maximal during the 6 h following lambing and dropped at 12 h. Protein and glucose concentrations were low in lambs at 1 h of birth after which they increased. By contrast, cortisol level was the highest during the first 12 h of birth and then decreased. The colostral IgG level was high at lambing and dropped by over 87 % from 1 to 48 h post-partum. In the newborn, the plasma IgG concentration was lowest at birth and increased rapidly during the first 24 h of birth. Parity influenced maternal physiology with multiparous ewes having the lowest concentrations of proteins, glucose, IgG and cortisol, but the highest colostrum IgG level. Accordingly, lambs born from primiparous ewes had lower protein, glucose and plasma IgG concentrations than lambs born from multiparous ewes. The main outcome of this study was that lambs born from primiparous ewes are characterized by the lowest physiological indices and this may influence their survival chance.

The onset of maternal responsiveness and the development of mother-young attachment in sheep are under the combined influence of hormonal and sensory stimulations. In the mother, the prepartum rise in oestrogen and vaginocervical stimulation caused by expulsion of the foetus act on the main olfactory system and on hypothalamic regions. This induces maternal care through the central release of oxytocin, modulated by opiates and corticotrophin-releasing hormone. In parallel, activation of the main olfactory network enables the learning of individual lamb odour and maternal attachment. In the neonate, the first suckling episodes and the concomitant activation of the cholecystokinin, opioids and oxytocin systems facilitate the development of a preference for the mother. Gastrointestinal signals activate the brain stem, the hypothalamus and the amygdala. Within 72 h of parturition, the mother-young attachment shifts from proximal to distal recognition based on visual and auditory cues after which vocal cues become more salient. Although olfaction remains a key element in the display of selective maternal nursing, maternal attachment relies on a multisensory mental image of the lamb. These findings support the view that sheep are amongst the most appropriate animal models for the study of maternal and filial attachment in mammals.

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.

International audience; Temperament influences maternal behavior and lamb survival in Merino sheep selected for calm or nervous temperament. The impact of this selection oil mother-young recognition and early expression of temperament ill lambs is unknown. We tested the ability of multiparous elves selected for calm (n = 16) or nervous (n = 18) temperament to recognize their own lambs 6 hr after parturition, the ability of the lambs to display a preference for their own mother at 18 hr; and the temperament of the lambs at 1 and 16 weeks of age. Elves and lambs from both genotypes showed a similar preference for their familiar kin. In contrast, differences lit temperament were detectable at l and 16 weeks of age. Nervous lambs showed higher vocal and locomotor activity than calm lambs. Thus, temperament did not affect the early process of ewe-lamb bonding but might affect the quality of the mother-young relationship under more challenging situations. (C) 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 429-438, 2009.

Stroking by humans is beneficial to the human-animal relationship and improves welfare in many species that express intraspecific allogrooming, but very few studies have looked at species like sheep that do not express such contact except around parturition. This study investigated the way lambs perceive regular human tactile contact using behavioral and physiological responses. Twenty-four lambs were reared and bucket-fed in groups of four. All were stroked daily by their familiar caregiver. At 8 weeks of age, the lambs were individually tested in their home pen but in a 1×1m open-barred pen after a 15 h period of habituation to physical separation from peers while remaining in visual and auditory contact. Half of the lambs received stroking by their caregiver for 8 min and half were exposed to their caregiver's immobile presence. Heart rate and heart rate variability were recorded and analyzed by 2-min slots over the same interval based on three measures: mean heart rate value (HR), root mean square of successive differences (RMSSD) and standard deviation of all intervals measured between consecutive sinus beats (SDNN). Behavioral responses (ear postures of the lamb and time spent in contact with the familiar caregiver, on the knees of the familiar caregiver, and moving) were recorded throughout the test. Lamb HR decreased continuously while in the presence of their caregiver. Lambs being stroked showed slower HR and higher RMSSD which reflected positive emotional states compared to lambs left unstroked. All behavioral variables were highly correlated with the main component axis of the PCA analyses: the more the animals stayed in contact with their caregiver, the less they moved and the more their ears were hanging. This first component clearly differentiates lambs being stroked or not. Behavioral and physiological observations support the hypothesis that gentle physical contact with the caregiver is perceived positively by lambs.

Social factors hypotheses predict that social segregation between male and female adult ungulates is due to social preferences among same-sex peers and avoidance of the opposite sex, rather than aggregation due to body size dimorphism and differential needs of the sexes. It is suggested that if such social preference/avoidance exists its roots should be early in life. While juvenile ungulate males show social preference for same-sex and same-age peers a few weeks after birth, no studies have confirmed such a phenomenon in juvenile females. In this study we investigated another possible mechanism that would result in an early social preference for same-sex conspecifics among juvenile females: we hypothesized that offspring–mother attachment is stronger for daughters than for sons. Attachment was measured in lambs, Ovis aries, using three characteristics defined initially in children: proximity seeking, distress following separation and exploration in the mother's presence. Lambs were tested at 3 weeks of age in two experimental situations in which they could interact with the mother, a familiar ewe or an unfamiliar ewe. (1) During a choice test between the mother and the familiar ewe, daughters maintained closer proximity with the mother than sons did. During the test without the mother (a familiar versus an unfamiliar ewe) daughters were more distressed than sons were. (2) In an isolation–reunion–separation test, reunion with the mother increased exploratory behaviour more in daughters than in sons. Overall, our results reveal that daughters displayed stronger attachment behaviours and could be more strongly attached to their mother than sons are. Such early preference may be a key factor leading to social preference among females and social segregation between the sexes.

Animals develop relationships with intra- and interspecific partners, including humans. In some cases this can lead to strong emotional bonds indicating the existence of attachment. The sheep is well known to develop various forms of social attachment (mothers towards young, lambs towards siblings). The relationship they can develop with humans is much less understood. In this review, based on the attachment theory framework developed in human infants, we outline features and mechanisms that participate in the development and the expression of affiliative behaviours that lambs can develop with their mother or a human. Behavioural tests comparing responses towards a presumed attachment figure with those directed towards unfamiliar or familiar conspecifics demonstrate that lambs do search specifically the proximity of their mother or human caregiver. Differential emotional responses in the presence (calmness) or the absence of the partner (agitation) are also expressed. However, a relationship with a human takes place more easily when lambs are reared without their primary attachment figure, the mother. Human-lamb attachment is then facilitated by positive social contacts (gentling, hand-feeding) provided by a specific caregiver. In the case of attachment with the mother, suckling is the main reward. Although the existence of a sensitive period is still unclear, in both cases attachment develops more rapidly if positive interactions take place immediately after birth. Three neurochemical systems have profound impact on the expression of filial attachment in sheep: the gut peptide cholecystokinin, endogenous opioids, and oxytocin, all known to play a key role in prosocial behaviours in mammals. In addition, positive nutritive or non-nutritive interactions activate specific brain regions that are involved in the expression of social and emotional behaviours. In conclusion, lambs do develop intra- and interspecific attachment but not in a concomitant manner as the presence of the mother strongly reduces their motivation to interact with a human. Nonetheless, under artificial rearing conditions the human becomes a salient attachment figure.

The aim of this study was to determine if repeated exposure to stressors of a different nature and intensity during the last 6 weeks of pregnancy modifies the reactivity of ewes to their lambs and to humans after lambing. Multiparous ewes were either subjected to 10 sessions of transport in isolation twice a week for 1 h (TRAN, n = 20 ewes), 10 sessions of isolation with or without the presence of a dog twice a week for 1 h (ISOL, n = 20 ewes) or no disturbance (CON, n = 19 ewes). Blood samples were collected during the 1st, 5th and 9th stress sessions for the TRAN and ISOL ewes and cortisol responses were measured. Maternal reactivity and fear of a human were measured during several challenge situations: 1 h after parturition (1) a human approached the lambing site at tagging and (2) a human held the lambs; 6 h after parturition, (3) the ewe was forced to cross a corridor to reach its lambs, (4) the ewe was forced to tolerate the presence of a human if it wished to remain close to its lambs and (5) the ewe was separated from its lambs; 1 month after parturition (6) a human approached the ewe and (7) the flight distance in response to a human was measured. A Principal Component Analysis was used to identify groups of statistically interrelated measures which otherwise would have remained undetected. During the 1st and the 9th sessions, transport in isolation provoked a greater cortisol release in ewes than isolation alone. However, ewes from both treatments habituated to the treatment with time. During the tests performed 1 h and 6 h after parturition, a clear divergence in reactivity was observed between treatments: ISOL ewes tried to maintain contact with their lambs in the presence of a human while TRAN ewes did not. CON ewes showed an intermediate response between ISOL and TRAN ewes. The divergence in behaviour persisted 1 month after parturition with ISOL ewes showing less avoidance of a human than TRAN ewes, CON ewes were intermediate. Correlations were found between cortisol responses and behavioural responses during the tests performed 1 h, 6 h and 1 month after lambing. The differences in ewe behaviour during challenge situations after lambing were probably not due to a weaker mother–young bond but to divergence in the effect of treatment during pregnancy on fear of humans: repeated isolation reduced fear of humans whereas repeated transport increased it.

The present study investigated the rewarding effects of nonnutritive sucking on the development of a filial preference. Two experiments were conducted to test whether nonnutritive visceral and oral stimuli have reinforcing properties independent from each other or act in synergy. Lambs could interact freely with their dam but were deprived of suckling by covering the udder for the first 12 hr. In Experiment 1, suckling was prevented and replaced by human giving, in the presence of the mother, either a bottle of water (B5 and B2.5: 5% or 2.5% birth weight, BW, divided into seven portions over 12 hr) or water via tube-feeding (I5 and I2.5: 5% or 2.5% BW, also divided into seven portions over 12 hr). During a two-choice test performed at 12 hr after birth, only B5 and I5 lambs preferred their mother to an alien ewe however, B5 were faster at choosing their mother at the beginning of the test. B2.5 and I2.5 lambs made a random choice. In Experiment 2, suckling was prevented and replaced by human giving, in the presence of the mother, either a bottle of water (B2.5: 2.5% BW, divided into seven portions over 12 hr) or water via tube-feeding (I10 and I2.5: 10% or 2.5% BW, also divided into seven portions over 12 hr). During a two-choice test at 12 hr, tube-fed lambs (I10 and I2.5) preferred their mother to a human. B2.5 lambs were equally attracted to both partners and spent more time near the human than lambs from the other groups. In a test of reactivity to a human performed on neonates isolated from their mother, B2.5 lambs explored the human much more than the other lambs. The presence of the human had soothing properties in B2.5 lambs and once the human left, they were the only lambs displaying enhanced vocal and locomotor activity. In these experiments, nonnutritive gastrointestinal stimuli induced a preference for the mother whereas nonnutritive sucking led to a strong positive relationship with the human. These results suggest that when lambs suckle their dam, the development of filial bonding is facilitated through the combined effects of oral and gastrointestinal stimuli. © 2006 Wiley Periodicals, Inc. Dev Psyshobiol 48: 220–232, 2006.

Consequences of prenatal stress on emotional reactivity and cognitive abilities in offspring are under-documented in precocial mammals. Here, we investigated to what extent emotional reactivity, judgment bias and spatial learning abilities of lambs are affected by chronic stress during late pregnancy and by their dams' emotional reactivity. The 20 highest-responsive (HR) and 20 lowest-responsive (LR) ewes from a population of 120 Romane ewes were selected according to their pre-mating reactivity to social isolation in a new environment. Over the final third of pregnancy, 10 HR ewes and 10 LR ewes were exposed daily to various unpredictable aversive events such as restraint, mixing groups and transport while the other 20 selected ewes were not. In a human and an object test, prenatally-stressed lambs were more fearful than control lambs, but the prenatal stress effect was moderated by the reactivity of the mothers: prenatally-stressed lambs from ewes with high emotional reactivity were more affected. Prenatally-stressed lambs did not perform as well as control lambs in a maze test and showed pessimistic-like judgment in a cognitive bias test. Prenatally-stressed lambs were thus characterized by a negative affective state with increased fear reactions and impaired cognitive evaluation. The development of negative moods could have long-lasting consequences on the coping strategies of the lambs in response to their rearing conditions.

Equipe Comportement, PRCUMR 6073 INRA/CNRS/Universite´ de ToursNouzilly, FranceE-mail: levy@tours.inra.frABSTRACT: Maternal behavior in sheep is characterized by the rapid establish-ment of individual recognition of the lamb through the use of different sensorymodalities. Olfactory recognition mediates acceptance at suckling whereas visual/auditory cues are involved in recognition from a distance. This study investigates(a)thetiming ofbothtypes ofrecognition and(b) whether theycan beinfluenced bymaternal experience. Olfactory recognition was assessed at lambing, 30 min, 1, 2,or 4 hr postpartum by presenting successively an alien and the familiar lamb.Recognitionatadistancewasassessedat6,8,and12hrpostpartumbyusingatwo-choice test between the familiar and an alien lamb. A majority (33/51) of ewesshowed selectivity at suckling as early as 30 min after parturition, and no differ-ences due to maternal experience were observed. By contrast, in the two-choicerecognition test, multiparous ewes showed a preference for their familiar lamb at6hrwhereasprimiparousmothersdidsoonly after24hrofmother–youngcontact:The performance of biparous mothers was intermediate. Thus, both types ofrecognition can be rapidly established after parturition, and maternal experiencehas a differential effect on the dynamics of these learning processes. 2003 Wiley Periodicals, Inc. Dev Psychobiol 43: 167–176, 2003.Keywords: bonding; maternal behavior; sheep; sensory recognition

Lambs can discriminate their own mother from an alien dam on the first day of life, suggesting the recognition of individual physical characteristics of the mother. Alternatively, their choice may depend on behavioral differences existing between the ewes because of their maternal selectivity. To clarify this, the ability of 24-hr-old lambs to discriminate between their own and an alien mother, that were either intact and accept only their own lamb at nursing (i.e., selective, n = 19) or anosmic, which nurse indiscriminately alien lambs as well as their own (i.e., nonselective, n = 24), was assessed by a 5-min, two-choice test. With intact dams, lambs spent significantly more time next to their own mother whereas this was not so in the presence of anosmic dams. Furthermore, in the intact group, the vocal activity by their own mother differed from that by the alien dam while this was not so in anosmic ewes. We conclude that 24-hr-old lambs rely more on the behavior of the ewes to select their dam than on their individual physical characteristics.

Remerciements : INRA-UE 0332-Domaine Expérimental Bourges-La Sapinière (BOURGES); Consequences of prenatal stress on mother–young relationships are well-documented in altricial mammals but less so in precocial mammals. In this study, we investigated the effects of unpredictable aversive events on maternal behavior and mutual mother–young recognition in pregnant ewes while accounting for modulatory effects of ewe reactivity. From a population of 120 Romane-breed ewes, we selected 20 high-responsive (HR) and 20 low-responsive (LR) ewes according to pre-mating reactivity assessed in isolation tests. Over the final third of pregnancy, 10 HR ewes and 10 LR ewes were exposed daily to various aversive events such as social isolation, mixing and transport (stressed ewes), while the other 20 ewes were not exposed to aversive events (control ewes). Although the treatment induced chronic stress, physiologically confirmed by an increase in salivary cortisol following transport and sham shearing, maternal behavior of stressed ewes observed during the first 30 min postpartum and in the selectivity test 1 h 30 min later did not differ from controls. However, in a maternal motivation test performed 48 h postpartum, stressed ewes vocalized less than controls when separated from their lambs, and walked less readily past an unknown object to reach their lambs. Lambs of stressed ewes spent more time near their dam in a preference test performed 15 h after birth compared to control-ewe lambs. HR ewes spent more time grooming their lambs than LR ewes. We posit that domestication could have selected animals displaying robust expression of maternal behavior related to social reactivity and producing offspring that are better adapted to challenging situations.

Providing piglets with repeated stroking and brushing leads to behaviours of affinity towards their handler, but there is still no evidence of physiological modifications. In addition, other tactile stimulations like scratching have not yet been studied while there are used by pig-keepers. Thus, the present experiment aimed at determining the consequences of stroking and scratching weaned piglets on their later behavioural, cortisol and cardiac responses to human presence and gentle tactile interactions. Four groups of four piglets were weaned at 28 days of age (Day 0) and handled twice a day for 10 min, five days a week, from Day 1 to 28. Handling consisted in standing for 30 s, sitting for 1 min and then stroking and scratching each piglet for 2 min. Four groups of four piglets were used as controls and received only the minimal contact for routine husbandry practices. Behavioural reactions to the presence of the handler in the home pen (Day 25) and to her presence and departure in an arena test (Days 26–27) were observed. Behavioural and cardiac responses to the handler’s presence and contact were compared in a test pen (Days 33–35). Salivary cortisol levels were measured in another test pen after 15-min of either contact with the handler or isolation (Days 40–43). In the home pen, handled piglets investigated sooner the handler (P0.05). Overall this study shows that scratching and stroking piglets during three weeks after weaning changed the way that they interacted with the handler, being more attracted than control piglets. However, there was no clear difference in cardiac reactions to scratching and stroking between handled and control piglets, suggesting that these contacts are perceived positively, regardless of the previous experience. The body region stimulated may be of importance but it needs further investigation.

This experiment investigates how the maternal presence influences the effect of additional human contact in early age on the reaction of lambs to their stockperson. Forty twin-born lambs were involved in this experiment during their first 4 days of life. Ten pairs of twins were reared artificially from 12h of age. One of each litter (AF, n=10) received 6.5+/-0.7 sessions of 30min of separation from the twin (with a wire fence) with 5min of gentling and feeding (suckling from a bottle and from a bucket fitted with a rubber teat). The other twin was not treated. Ten pairs of twins were reared with their dam and received 6.6+/-0.7 sessions of treatment. One twin (MAF, n=10) received the same treatment as AF. The other twin (M, n=10) was separated for 30min from the dam and had no human contact. From the age of 70+/-7h, lambs were tested in a social isolation test (alone for 1min, with the familiar stockman for 2min, alone again for 1min), in a Preference test (2min) between an unfamiliar maternal ewe and the familiar stockman, and, for the AF lambs only, in a Preference test (2min) between their familiar and an unfamiliar stockman. Eight AF lambs learned to suck on their own from the bucket of milk by the end of the experiment compared to only one MAF (P0.001). AF lambs approached the human more (P0.01), vocalised less (P0.01) and walked less (P0.01) during the social isolation test than animals reared with their mother (M and MAF). AF did not show any preference between the stockman and the unfamiliar maternal ewe while M and MAF lambs chose the ewe (P0.05). AF lambs discriminated the familiar from an unfamiliar stockman only if they had learned to suck from the bucket during the treatment. Nevertheless MAF lambs vocalised less than M (P0.05) in the presence of the stockman during the social isolation test, indicating a possible reduction of isolation distress. These results show that artificially reared lambs are preferentially motivated to interact with a familiar human after only a few days of contact. Moreover, they highlight the difficulty in using a feeding reward to improve the human-lamb relationship when lambs are reared permanently with their dams. However, the results suggest that early gentling improves the human-animal relationship whatever the maternal environment.

The defining characteristic of mammals is that females nurse and care for their young; without this, the neonate has no chance to survive. Studies on wild and domestic species show that the neonatal period is the most critical step in the lifetime of a mammal. This review compares three well-studied species (the rabbit, pig and sheep) that differ in their parental strategies and in the problems that neonates have to overcome. As a general trend, mother-young interactions vary according to the maturity of the newborn, and the size of the litter. Neonatal survival relies to a great extent on an environment that is ecologically appropriate for the developmental stage of the neonate, and on optimum interactions with the mother. Adaptive maternal care supposes that the mother provides the basic needs of the neonate: warmth (in pigs and rabbits) or shelter, food, water and immunological protection (via colostrum) and, in some instances, protection from predators and other conspecifics. A major risk facing all neonates, other than the birth process itself, is inadequate colostrum intake owing to delayed suckling or competition with siblings, which leads to starvation, hypothermia or even crushing, as has been observed in pigs.

Two studies were carried out to test the ability of Prealpes du Sud x Lacaune (Study 1) and Rambouillet ewes (Study 2) to recognize their lambs during the first 24 h postpartum. Ewes were given the choice between their own and an alien lamb of approximately the same age, in a triangular pen of 10 m×10 m×10 m. A lamb was placed in each of the two corners while the mother was released from the third corner. Direct access to the lambs was prevented by an open barrier located at 1 m from the pens in which the lambs were kept. Ewes were studied at 8 h (n=10, 12), 12 h (n=20, 10) and 24 h postpartum (n=29, 9; Study 1 and Study 2 respectively). Tests lasted 3 and 5 min in Study 1 and 2, respectively. Although the first choice of the ewes did not differ from random, in both studies mothers spent significantly more time near their own lamb than near the alien. In both breeds a significant preference for the own lamb was already present at 8 h (P

The first sucking bouts have strong rewarding properties in the establishment of a preference for the mother by newborn lambs. In this study we designed an artificial teat (Experiment 1) and a method of tube feeding (Experiment 2) to investigate the role of nonnutritive sucking and colostrum intake as reinforcers in the development of this relationship (Experiment 3). In this third experiment, lambs of the control group (n = 10) had free access to the udder. In the other groups they were prevented from sucking between birth and 6 h by covering the ewe's udder while lambs received one of the following treatments: access to nonnutritive teats fitted onto the mother's udder (n= 12), tube fed with colostrum (n = 11), or fully deprived (n = 10). When tested in a two-choice test at 24 h of age, controls and lambs receiving colostrum spent significantly more time near their mother than near the alien ewe. By contrast, deprived lambs did not. Half of the lambs having access to nonnutritive teats displayed a preference for their mother; the other half chose the alien ewe. However, most lambs that were affected by the treatments displayed a preference for their mother when a second test was performed at 48 h. In conclusion, these results demonstrate that a neonatal nasogastric infusion of colostrum has the same rewarding properties as a complete sucking bout. They also provide evidence for the first time that a relationship with the dam can be established via a nutritional signal originating from the gastrointestinal sphere.