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Briefer Freymond, S.; Briefer, E.F.; Niederhäusern, R.V.; Bachmann, I. |
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Title |
Pattern of Social Interactions after Group Integration: A Possibility to Keep Stallions in Group |
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Journal Article |
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2013 |
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PLoS ONE |
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PLoS ONE |
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8 |
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1 |
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e54688 EP - |
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<p>Horses are often kept in individual stables, rather than in outdoor groups, despite such housing system fulfilling many of their welfare needs, such as the access to social partners. Keeping domestic stallions in outdoor groups would mimic bachelor bands that are found in the wild. Unfortunately, the high level of aggression that unfamiliar stallions display when they first <italic>encounter each other</italic> discourages owners from keeping them in groups. However, this level of aggression is likely to be particularly important only during group integration, when the dominance hierarchy is being established, whereas relatively low aggression rates have been observed among stable feral bachelor bands. We investigated the possibility of housing breeding stallions owned by the Swiss National Stud in groups on a large pasture (5 stallions in 2009 and 8 stallions in 2010). We studied the pattern of agonistic, ritual and affiliative interactions after group integration (17–23 days), and the factors influencing these interactions (time after group integration, dominance rank, age or experience of group housing). We found that stallions displayed generally more ritual than agonistic and than affiliative interactions. The frequency of agonistic and ritual interactions decreased quickly within the first three to four days. The frequency of affiliative interactions increased slowly with time before decreasing after 9–14 days. A stable hierarchy could be measured after 2–3 months. The highest-ranking males had less ritual interactions than the lowest-ranking. Males had also less agonistic, ritual and affiliative interactions if they had already been housed in a group the previous year. Therefore, we found that breeding stallions could be housed together on a large pasture, because the frequency of agonistic interactions decreased quickly and remained at a minimal level from the fourth day following group integration. This housing system could potentially increase horse welfare and reduce labour associated with horse management.</p> |
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Public Library of Science |
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Equine Behaviour @ team @ |
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5656 |
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Benson-Amram, S.; Weldele, M.L.; Holekamp, K.E. |
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A comparison of innovative problem-solving abilities between wild and captive spotted hyaenas, Crocuta crocuta |
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2013 |
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Animal Behaviour |
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85 |
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2 |
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349-356 |
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Crocuta crocuta; innovation; neophobia; problem solving; spotted hyaena |
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Innovative problem solving enables individuals to deal with novel social and ecological challenges. However, our understanding of the importance of innovation for animals in their natural habitat is limited because experimental investigations of innovation have historically focused on captive animals. To determine how captivity affects innovation, and whether captive studies of animal innovation suffer from low external validity, we need experimental investigations of innovation in both wild and captive populations of the same species in diverse taxa. Here we inquired whether wild and captive spotted hyaenas differ in their ability to solve the same novel technical problem, and in the diversity of exploratory behaviours they exhibit when first interacting with the problem. Our results suggest that wild and captive populations show important differences in their innovative problem-solving abilities. Captive hyaenas were significantly more successful at solving the novel problem, and significantly more diverse in their initial exploratory behaviour, than were wild hyaenas. We were able to rule out hypotheses suggesting that these differences result from excess energy or time available to captive animals. We conclude that captive hyaenas were more successful because captive individuals were less neophobic and more exploratory than their wild counterparts. These results have important implications for our interpretation of studies on innovative problem solving in captive animals and aid our attempts to gain a broader understanding of the importance of innovation for animals in their natural habitat. |
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0003-3472 |
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Equine Behaviour @ team @ |
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5657 |
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Clucas, B.; Marzluff, J.M.; Mackovjak, D.; Palmquist, I. |
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Do American Crows Pay Attention to Human Gaze and Facial Expressions? |
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Year |
2013 |
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Ethology |
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Ethology |
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119 |
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4 |
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296-302 |
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Interactions between species can lead to the evolution of interspecific communication. Non-verbal communication by humans, both intentional and unintentional, can be interpreted by other species. We tested whether American crows (Corvus brachyrhynchos) were sensitive to human facial features under field conditions by comparing flight initiation distances and urgency of escape behavior to human approaches varying in eye contact and facial expression. We first examined whether crows distinguish between an approaching human who is directly gazing at them and a human approaching them with an averted gaze. In a second experiment, we tested whether crows differentiate a smiling from scowling human approaching them with direct or averted gaze. In the first experiment, we found that crows fled sooner and more urgently when humans were directly gazing at them. Similarly, in the second experiment, crows responded sooner to a direct vs. averted gaze; however, they did not react differently to varying human facial expressions. We suggest that crows use human gaze as a reliable visual cue compared with facial expressions when making decisions about responding to approaching humans. This is the first study to show that a wild corvid species changes its behavior based on human gaze, possibly representing an adaptation to living in human-dominated urban areas and suggesting crows might perceive human intention by this visual cue. |
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1439-0310 |
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Equine Behaviour @ team @ |
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5670 |
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Proops, L.; Rayner, J.; Taylor, A.M.; McComb, K. |
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The Responses of Young Domestic Horses to Human-Given Cues |
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2013 |
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PLoS ONE |
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PLoS ONE |
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8 |
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6 |
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e67000 EP - |
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<p>It has been suggested that the process of domestication, at least in some species, has led to an innate predisposition to be skilled at reading human communicative and attentional cues. Adult domestic horses (<italic>Equus caballus</italic>) are highly sensitive to subtle bodily cues when determining if a person is attending to them but they are less adept at using human communicative cues in object choice tasks. Here we provide the first study into the ontogeny of such skills in order to gain insights into the mechanisms underlying these abilities. Compared with adult horses, youngsters under the age of three could use body orientation but not more subtle cues such as head movement and open/closed eyes to correctly choose an attentive person to approach for food. Across two object choice experiments, the performance of young horses was comparable to that of adult horses – subjects were able to correctly choose a rewarded bucket using marker placement, pointing and touching cues but could not use body orientation, gaze, elbow pointing or tapping cues. Taken together these results do not support the theory that horses possess an innate predisposition to be particularly skilled at using human cues. Horses' ability to determine whether humans are attending to them using subtle body cues appears to require significant experience to fully develop and their perhaps less remarkable use of limited cues in object choice tasks, although present at a much earlier age, is likely to reflect a more general learning ability related to stimulus enhancement rather than a specific ‘human-reading’ skill.</p> |
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Public Library of Science |
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Equine Behaviour @ team @ |
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5676 |
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Begall, S.; Malkemper, E.P.; Cervený, J.; Nemec, P.; Burda, H. |
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Magnetic alignment in mammals and other animals |
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Journal Article |
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2013 |
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Mammalian Biology – Zeitschrift für Säugetierkunde |
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Mamm. Biol. |
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78 |
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1 |
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10-20 |
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Cattle; Deer; Fox; Horse; Magnetoreception |
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Magnetic alignment (MA) constitutes the simplest directional response to the geomagnetic field. In contrast to magnetic compass orientation, MA is not goal directed and represents a spontaneous, fixed directional response. Because animals tend to align their bodies along or perpendicular to the magnetic field lines, MA typically leads to bimodal or quadrimodal orientation, although there is also growing evidence for a fixed unimodal orientation not necessarily coinciding with the magnetic cardinal directions. MA has been demonstrated in diverse animals including insects, amphibians, fish, and mammals. Alignment can be expressed by animals during resting as well as on the move (e.g. while grazing, hunting, feeding, etc.). Here, we briefly survey characteristic features and classical examples of MA and review the current knowledge about the occurrence of MA in mammals. In addition, we summarize what is known about mechanisms underlying MA and discuss its prospective biological functions. Finally, we highlight some physiological effects of alignment along the magnetic field axes reported in humans. We argue that the phenomenon of MA adds a new paradigm that can be exploited for investigation of magnetoreception in mammals. |
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1616-5047 |
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Equine Behaviour @ team @ |
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5678 |
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Larsson, M. |
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The optic chiasm: a turning point in the evolution of eye/hand coordination |
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2013 |
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Frontiers in Zoology |
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Front. Zool. |
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10 |
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1 |
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41 |
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The primate visual system has a uniquely high proportion of ipsilateral retinal projections, retinal ganglial cells that do not cross the midline in the optic chiasm. The general assumption is that this developed due to the selective advantage of accurate depth perception through stereopsis. Here, the hypothesis that the need for accurate eye-forelimb coordination substantially influenced the evolution of the primate visual system is presented. Evolutionary processes may change the direction of retinal ganglial cells. Crossing, or non-crossing, in the optic chiasm determines which hemisphere receives visual feedback in reaching tasks. Each hemisphere receives little tactile and proprioceptive information about the ipsilateral hand. The eye-forelimb hypothesis proposes that abundant ipsilateral retinal projections developed in the primate brain to synthesize, in a single hemisphere, visual, tactile, proprioceptive, and motor information about a given hand, and that this improved eye-hand coordination and optimized the size of the brain. If accurate eye-hand coordination was a major factor in the evolution of stereopsis, stereopsis is likely to be highly developed for activity in the area where the hands most often operate.The primate visual system is ideally suited for tasks within arm's length and in the inferior visual field, where most manual activity takes place. Altering of ocular dominance in reaching tasks, reduced cross-modal cuing effects when arms are crossed, response of neurons in the primary motor cortex to viewed actions of a hand, multimodal neuron response to tactile as well as visual events, and extensive use of multimodal sensory information in reaching maneuvers support the premise that benefits of accurate limb control influenced the evolution of the primate visual system. The eye-forelimb hypothesis implies that evolutionary change toward hemidecussation in the optic chiasm provided parsimonious neural pathways in animals developing frontal vision and visually guided forelimbs, and also suggests a new perspective on vision convergence in prey and predatory animals. |
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1742-9994 |
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Equine Behaviour @ team @ |
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5685 |
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Flauger, B.; Krueger, K. |
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Aggressionslevel und Platzangebot bei Pferden (Equus caballus) [ Aggression level and enclosure size in horses (Equus caballus)] |
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2013 |
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Pferdeheilkunde |
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29 |
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4 |
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495-504 |
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Aggression / Verletzungsgefahr / Sozialverhalten / Gruppenhaltung / Pferdehaltung / Eingliederung von Pferden [aggression / injury risk / social behaviour / group housing / horse management / introduction of horses] |
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Viele Pferdebesitzer bevorzugen aus Angst vor aggressiven Interaktionen und Verletzungsgefahr der Tiere untereinander die Einzelhaltung, obwohl von Tierschutzorganisationen die Gruppenhaltung für Pferde empfohlen wird. In dieser Studie beobachteten wir während des alltäglichen Soziallebens als auch bei der Eingliederung von neuen Gruppenmitgliedern das Sozialverhalten, insbesondere das Aggressionsverhalten, von elf Gruppen domestizierter Pferde (Equus caballus) verschiedener Größe und Zusammensetzung. Während des alltäglichen Soziallebens hatten die Gruppe und der Paddock-Typ (Gras / kein Gras) keinen Einfluss auf die Verhaltensweisen, wohingegen die Paddockgröße unter 10000 m2 einen signifikanten Einfluss auf die submissiven Verhaltensweisen (GzLM; n=56; t=-2.061, P=0.044) und einen nicht signifikanten Einfluss auf die aggressiven Verhaltensweisen (GzLM; n=56; t=-1.782, P=0.081) hatte. Allerdings verringerten sich sowohl die aggressiven als auch die submissiven Verhaltensweisen mit steigendem Platzangebot bis zu 10000 m2 (Spearman rank Korrelation; n=56; aggressive Verhaltensweisen: r = -0.313, P = 0.019; submissive Verhaltensweisen: r = -0.328, P = 0.014). Während den Eingliederungen reduzierten sich die Aggressionen pro Stunde mit der Vergrößerung des Platzangebotes (Spearman rank Korrelation; n=28; r=-0.402, P=0.034). Dies zeigte sich noch deutlicher, wenn Beobachtungen mit einem Platzangebot von über 10000 m2 ausgeschlos- sen wurden (Spearman rank Korrelation; n=23; r=-0.549, P=0.007). Während des alltäglichen Soziallebens näherte sich der Aggressionslevel der Nulllinie an, wenn das Platzangebot pro Pferd mehr als 331 m2 betrug. Deshalb empfehlen wir zur Reduzierung des Aggressionslevels und des Verletzungsrisikos von sozial gehaltenen Pferdegruppen ein Platzangebot von mindestens 331 m2 pro Pferd.
[Even though animal welfare organisations propose group housing for horse welfare, many owners stable horses individually for fear of aggressive interactions and injury risks. In the present study we observed social behaviour, and especially aggressiveness, in eleven domestic horse groups (Equus caballus) of different size and composition, in basic social situations and when new group members were introduced. During basic social situations, the group and the type of paddock (grass / no grass) had no effect on any of the behaviours, where- as the enclosure size below 10,000 m2 had a significant effect on submissive behaviour (GzLM; n=56; t=-2.061, P=0.044) and an insignificant effect on aggressive behaviour (GzLM; n=56; t=-1.782, P=0.081). However, aggressive and submissive behaviour dimi- nished with the increase of enclosure sizes up to 10,000 m2 (Spearman rank correlation; n = 56; aggressive behaviour: r = -0.313, P=0.019; submissive behaviour: r=-0.328, P=0.014). During introductions, aggression levels per hour decreased with any increase of enclosure size (Spearman rank correlation; n=28; r=-0.402, P=0.034) and even more when enclosure sizes above 10,000 m2 were excluded (Spearman rank correlation; n=23; r=-0.549, P=0.007). During basic social situations the aggression level approached zero when the space allowance was more than 331 m2 per horse. We therefore recommend keeping horse groups in an enclosure with at least 331 m2 per horse to reduce aggression and injuries.] |
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Equine Behaviour @ team @ |
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5714 |
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Viry, S.; Sleimen-Malkoun, R.; Temprado, J.-J.; Frances, J.-P.; Berton, E.; Laurent, M.; Nicol, C. |
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Title |
Patterns of Horse-Rider Coordination during Endurance Race: A Dynamical System Approach |
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Journal Article |
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2013 |
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PLoS ONE |
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PLoS ONE |
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8 |
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8 |
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e71804 EP - |
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<p>In riding, most biomechanical studies have focused on the description of the horse locomotion in unridden condition. In this study, we draw the prospect of how the basic principles established in inter-personal coordination by the theory of <italic>Coordination Dynamics</italic> may provide a conceptual and methodological framework for understanding the horse-rider coupling. The recent development of mobile technologies allows combined horse and rider recordings during long lasting natural events such as endurance races. Six international horse-rider dyads were thus recorded during a 120 km race by using two tri-axial accelerometers placed on the horses and riders, respectively. The analysis concentrated on their combined vertical displacements. The obtained shapes and angles of Lissajous plots together with values of relative phase between horse and rider displacements at lower reversal point allowed us to characterize four coordination patterns, reflecting the use of two riding techniques per horse's gait (trot and canter). The present study shows that the concepts, methods and tools of self-organizing dynamic system approach offer new directions for understanding horse-rider coordination. The identification of the horse-rider coupling patterns constitutes a firm basis to further study the coalition of multiple constraints that determine their emergence and their dynamics in endurance race.</p> |
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Equine Behaviour @ team @ |
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5706 |
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Gil, M.; Bhatt, R.; Picotte, K.B.; Hull, E.M. |
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Sexual experience increases oxytocin receptor gene expression and protein in the medial preoptic area of the male rat |
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2013 |
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Psychoneuroendocrinology |
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Psychoneuroendocrinology |
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38 |
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9 |
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1688-1697 |
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Oxytocin; Oxytocin receptor; Sexual behavior; Sexual experience; Medial preoptic area; Hypothalamus; Rats |
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Oxytocin (OT) promotes social and reproductive behaviors in mammals, and OT deficits may be linked to disordered social behaviors like autism and severe anxiety. Male rat sexual behavior is an excellent model for OT regulation of behavior, as its pattern and neural substrates are well characterized. We previously reported that OT microinjected into the medial preoptic area (MPOA), a major integrative site for male sexual behavior, facilitates copulation in sexually experienced male rats, whereas intra-MPOA injection of an OT antagonist (OTA) inhibits copulation. In the present studies, copulation on the day of sacrifice stimulated OTR mRNA expression in the MPOA, irrespective of previous sexual experience, with the highest levels observed in first-time copulators. In addition, sexually experienced males had higher levels of OTR protein in the MPOA than sexually naïve males and first-time copulators. Finally, intra-MPOA injection of OT facilitated mating in sexually naive males. Others have reported a positive correlation between OT mRNA levels and male sexual behavior. Our studies show that OT in the MPOA facilitates mating in both sexually naive and experienced males, some of the behavioral effects of OT are mediated by the OTR, and sexual experience is associated with increased OTR expression in the MPOA. Taken together, these data suggest a reciprocal interaction between central OT and behavior, in which OT facilitates copulation and copulation stimulates the OT/OTR system in the brain. |
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Pergamon Press. |
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0306-4530 |
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Equine Behaviour @ team @ S0306-4530(13)00040-1 |
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5724 |
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Sebilo, M.; Mayer, B.; Nicolardot, B.; Pinay, G.; Mariotti, A. |
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Long-term fate of nitrate fertilizer in agricultural soils |
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Journal Article |
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2013 |
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Proceedings of the National Academy of Sciences |
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PNAS |
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Increasing diffuse nitrate loading of surface waters and groundwater has emerged as a major problem in many agricultural areas of the world, resulting in contamination of drinking water resources in aquifers as well as eutrophication of freshwaters and coastal marine ecosystems. Although empirical correlations between application rates of N fertilizers to agricultural soils and nitrate contamination of adjacent hydrological systems have been demonstrated, the transit times of fertilizer N in the pedosphere–hydrosphere system are poorly understood. We investigated the fate of isotopically labeled nitrogen fertilizers in a three–decade-long in situ tracer experiment that quantified not only fertilizer N uptake by plants and retention in soils, but also determined to which extent and over which time periods fertilizer N stored in soil organic matter is rereleased for either uptake in crops or export into the hydrosphere. We found that 61–65% of the applied fertilizers N were taken up by plants, whereas 12–15% of the labeled fertilizer N were still residing in the soil organic matter more than a quarter century after tracer application. Between 8–12% of the applied fertilizer had leaked toward the hydrosphere during the 30-y observation period. We predict that additional exports of 15N-labeled nitrate from the tracer application in 1982 toward the hydrosphere will continue for at least another five decades. Therefore, attempts to reduce agricultural nitrate contamination of aquatic systems must consider the long-term legacy of past applications of synthetic fertilizers in agricultural systems and the nitrogen retention capacity of agricultural soils. |
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Equine Behaviour @ team @ |
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5730 |
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