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Kuczaj, S. A., Makecha, R., Trone, M., Paulos, R. D., & Ramos, J. A. (2006). Role of Peers in Cultural Innovation and Cultural Transmission: Evidence from the Play of Dolphin Calves. Int. J. Comp. Psychol, 19(2), 223–240.
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Murphy, J., & Arkins, S. (2006). Laterality and visuo-spatial ability in the equine: Functional measures of sport horse selection? BSAP Occasional Publication, 35, 159–170.
Abstract: Laterality in any organism or species can be manifest as morphological, sensory and functional degrees of asymmetry such as hemispheric dominance, handedness or sidedness and other motor functional behaviours and as such is equally important in equitation. The influence of the horses' sex on both the direction and the degree of the laterality was explored within and between 4 experimental procedures in the 1st study. The findings showed that the direction, but not the degree of idiosyncratic motor preference in the horses was strongly sex-related. Male horses exhibited significantly more left lateralized responses and female horses exhibited significantly more right lateralized responses. Visuo-spatial ability is also likely to be important in the performance horse. In many species, moderate to large differences in visuo-spatial ability have been reported between the sexes, with superior visuo-spatial ability being reported in males of all species investigated to date. As no known studies had addressed visuo-spatial ability in the equine, the objective of the 2nd study, was to determine if visuo-spatial ability differed between male and female horses. The results produced the first behavioural demonstration of superior visuo-spatial ability in male horses, similar to that reported in other species. There is evidence to suggest that visuospatial ability and motor laterality are associated with cerebral hemispheric asymmetry and may be intrinsically linked. Brain development and laterality have also been associated with hair patterning, and, in a 3rd study we attempted to identify predictors of lateral bias in motor behaviour in horses. We investigated the relationship between the direction of facial hair whorl rotation and the incidence/direction of laterality in the horse. The findings suggest that direction of facial hair whorl rotation may be a useful indicator of lateralised motor behavioural preferences in the horse. We then attempted to establish if laterality was evident at birth in a 4th study, where we explored if neonatal foals exhibited lateralised patterns during and immediately post the birthing process that were correlated with their facial hair whorl patterns. The results showed a significant association between the sex of the foal and the choice of foreleg presented initially during 2nd stage parturition. Significantly more colt foals led with the left foreleg and significantly more filly foals led with the right foreleg than expected purely by random and the behaviour was correlated with facial hair whorl patterns. The findings also suggest that lateralisation in the horse is determined in utero as has also been shown in humans. Comparisons of wholly intact male and female horses are warranted as they might elucidate additional linkages between motor behaviour, visuo-spatial ability and brain organisation and development in the horse. Further research in this area could lead to more appropriate competition conditions (better fence design/construction on cross-country tracks) and so eliminate unnecessary levels of risk associated with many equestrian sports.
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Nowak, S., Jedrzejewski, W., Schmidt, K., Theuerkauf, J., Myslajek, R. W., & Jedrzejewska, B. (2006). Howling activity of free-ranging wolves (Canis lupus) in the Bialowieza Primeval Forest and the Western Beskidy Mountains (Poland). J Ethol, 25.
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Berger, K. M. (2006). Carnivore-Livestock conflicts: effects of subsidized predator control and economic correlates on the sheep industry. Conserv Biol, 20.
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Lim, M. M., & Young, L. J. (2006). Neuropeptidergic regulation of affiliative behavior and social bonding in animals. Hormon. Behav., 50(4), 506–517.
Abstract: Social relationships are essential for maintaining human mental health, yet little is known about the brain mechanisms involved in the development and maintenance of social bonds. Animal models are powerful tools for investigating the neurobiological mechanisms regulating the cognitive processes leading to the development of social relationships and for potentially extending our understanding of the human condition. In this review, we discuss the roles of the neuropeptides oxytocin and vasopressin in the regulation of social bonding as well as related social behaviors which culminate in the formation of social relationships in animal models. The formation of social bonds is a hierarchical process involving social motivation and approach, the processing of social stimuli and formation of social memories, and the social attachment itself. Oxytocin and vasopressin have been implicated in each of these processes. Specifically, these peptides facilitate social affiliation and parental nurturing behavior, are essential for social recognition in rodents, and are involved in the formation of selective mother-infant bonds in sheep and pair bonds in monogamous voles. The convergence of evidence from these animal studies makes oxytocin and vasopressin attractive candidates for the neural modulation of human social relationships as well as potential therapeutic targets for the treatment of psychiatric disorders associated with disruptions in social behavior, including autism.
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Fagot, J., & Cook, R. G. (2006). Evidence for large long-term memory capacities in baboons and pigeons and its implications for learning and the evolution of cognition. Proc Natl Acad Sci U S A, 103.
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Leiner, L. (2006). Vergleich verschiedener Methoden zur Angstextinktion bei Pferden. Diploma thesis, , .
Abstract: Pferde sind Fluchttiere. Ihr Fluchtinstinkt bewirkt, dass sie sich leicht erschrecken und auch in
diversen Situationen mit Flucht reagieren. Diese Tatsache ist den meisten Reitern bekannt,
nur ist es für den Menschen teilweise schwer, mit dieser Eigenschaft auszukommen und sie zu
verstehen oder gar nachzuvollziehen. So kommt es häufig zu Unfällen, die aus der Angst der
Pferde resultieren, jedoch vermeidbar gewesen wären, hätte man ankündigende Signale früher
erkannt. Des Weiteren kann die Angst eines Pferdes auch durch eine (Ver-) Weigerung,
bestimmte Dinge zu tun, sichtbar werden. Diese Weigerung wird in der Reiterei gerne als
„Bockigkeit“ und „Ungehorsam“ des Pferdes interpretiert und führt nicht selten zu einer
Bestrafung. Insgesamt kann man sagen, dass angstauslösende Reize und die Reaktionen des
Pferdes darauf oft falsch eingeschätzt oder falsch interpretiert werden und in der Folge auch
falsch damit umgegangen wird. Ein Grund dafür ist sicher das fehlende Wissen über das
Verhalten des Pferdes. Mit der vorliegenden Diplomarbeit soll ein Beitrag geleistet werden,
das Pferd in seinem Angstverhalten besser zu verstehen. Ziel der Arbeit war es, das Verhalten
des Pferdes bei verschiedenen Intensitäten von Angst zu untersuchen. Des Weiteren wurden
Methoden untersucht, mit denen man die Angst von Pferden vor bestimmten Reizen und
Situationen potentiell lindern kann, was letztendlich auch der Unfallvorbeugung dient.
Die vorliegende Diplomarbeit wurde am Haupt- und Landesgestüt Marbach durchgeführt; 24
Junghengste standen hierfür zur Verfügung. Darunter waren 18 Deutsche Warmblüter, 3
Vollblutaraber und 3 Schwarzwälder Füchse (Kaltblüter), somit war auch ein Rassenvergleich
möglich.
In einem ersten Teil der Arbeit wurde untersucht, wie sich Angst bei Pferden äußert. Hierfür
wurde ausgenutzt, dass Pferde ganz generell vor unbekannten, neuen Gegenständen Angst
haben (= Neophobie). Zur Angstauslösung dienten als Konfrontationsgegenstände ein
Sonnenschirm und eine Plastikplane. Beide Gegenstände waren für die Testpferde unbekannt.
Das Verhalten sowie die Herzrate der Tiere wurden während aller Versuche beobachtet und
quantifiziert. Nacheiner ersten Konfrontation wurden die Pferde an die Objekte gewöhnt
(Extinktionstraining = Angstlöschung) und beobachtet welche Verhaltensymptome sich
während dieser Gewöhnung (= Verlust der Neophobie) verändern. Die Hypothese war, dass
tatsächliche Angstsymptome während der Gewöhnung immer seltener zu beobachten sind.
Zusammenfassung III
Als Verhaltensweisen für Angst konnten Ausweichbewegungen und Flucht, Lautäußerungen
(Prusten und Schnauben), das Anspannen der Halsmuskulatur sowie das Vordrücken der
Oberlippe identifiziert werden. Darüber hinaus wurde gezeigt, dass Abstufungen im
Angstverhalten möglich sind: Bei sehr hohem Angstlevel sind Fluchtreaktionen zu
beobachten. Bei mittlerem Angstlevel treten Ausweichbewegungen im Schritt und
Lautäußerungen (Prusten und Schnauben) auf, bei geringem Angstlevel wird die
Halsmuskulatur angespannt und die Oberlippe vorgedrückt.
Im Zweiten Teil der Arbeit sollten verschiedene Methoden zur Angst-Extinktionauf ihre
Wirksamkeit hin untersucht werden. Verwendet wurde in verschiedenen Testgruppen die
Methode der Desensibilisierung (d.h. leichte, schrittweise stärker werdende Exposition
gegenüber dem angstauslösenden Reiz), die Desensibilisierung mit Gegenkonditionierung
(positive Verstärkung) durch Streicheln bzw. Reiben des Halses und die Desensibilisierung
mit Gegenkonditionierung durch Futterbelohnung. Als Kontrollgruppe dienten Pferde, die
ohne eine Konfrontation mit dem angstauslösenden Reiz nur über den Versuchplatz geführt
wurden.
Während des Extinktionstrainings konnte beobachtet werden, dass die Desensibilisierung mit
Gegenkonditionierung zu einer schnelleren Extinktion führt als ohne Gegenkonditionierung.
Allerdings zeigte ein Vergleich mit der Kontrollgruppe, die das Extinktionstraining nicht
erfahren hatte, den gleichen Verlust an Angstverhalten wie die Gruppen mit Extinktionstraining.
Dieses Ergebnis wurde so interpretiert, dass die wiederholte Exposition gegenüber
angstauslösenden Reizen bei den durchgeführten Verhaltenstests zwar eine Rolle spielt, doch
dass auch allein die Beschäftigung mit den Tieren zu einem Verlust von Angstverhalten führt
(wahrscheinlich auch aufgrund eines wachsenden Vertrauens zur Führperson, die über das
komplette Experiment hin die Gleiche blieb).
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de Cocq, P., van Weeren, P. R., & Back, W. (2006). Saddle pressure measuring: Validity, reliability and power to discriminate between different saddle-fits. The Veterinary Journal, 172(2), 265–273.
Abstract: Saddle-fit is recognised as an important factor in the pathogenesis of back problems in horses and is empirically being evaluated by pressure measurements in clinical practice, although not much is known about the validity, reliability and usability of these devices in the equine field. This study was conducted to assess critically a pressure measurement system marketed for evaluating saddle fit. Validity was tested by calculating the correlation coefficient between total measured pressure and the weight of 28 different riders. Reliability and discriminative power with respect to different saddle fitting methods were evaluated in a highly standardised, paired measurement set-up in which saddle-fit was quantified by air-pressure values inside the panels of the saddle. Total pressures under the saddle correlated well with riders’ weight. A large increase in over-day sensor variation was found. Within trial intra-class correlation coefficients (ICCs) were excellent, but the between trial ICCs varied from poor to excellent and the variation in total pressure was high. In saddles in which the fit was adjusted to individual asymmetries of the horse, the pressure measurement device was able to detect correctly air-pressure differences between the two panels in the back area of the saddle, but not in the front area. The device yielded valid results, but was only reliable in highly standardised conditions. The results question the indiscriminate use of current saddle pressure measurement devices for the quantitative assessment of saddle-fit under practical conditions and suggest that further technical improvement may be necessary.
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Czeh, B., Muller-Keuker, J. I. H., Rygula, R., Abumaria, N., Hiemke, C., Domenici, E., et al. (2006). Chronic Social Stress Inhibits Cell Proliferation in the Adult Medial Prefrontal Cortex: Hemispheric Asymmetry and Reversal by Fluoxetine Treatment. Neuropsychopharmacology, 32(7), 1490–1503.
Abstract: Profound neuroplastic changes have been demonstrated in various limbic structures after chronic stress exposure and antidepressant treatment in animal models of mood disorders. Here, we examined in rats the effect of chronic social stress and concomitant antidepressant treatment on cell proliferation in the medial prefrontal cortex (mPFC). We also examined possible hemispheric differences. Animals were subjected to 5 weeks of daily social defeat by an aggressive conspecific and received concomitant, daily, oral fluoxetine (10 mg/kg) during the last 4 weeks. Bromodeoxyuridine (BrdU) labeling and quantitative stereological techniques were used to evaluate the treatment effects on proliferation and survival of newborn cells in limbic structures such as the mPFC and the hippocampal dentate gyrus, in comparison with nonlimbic structures such as the primary motor cortex and the subventricular zone. Phenotypic analysis showed that neurogenesis dominated the dentate gyrus, whereas in the mPFC most newborn cells were glia, with smaller numbers of endothelial cells. Chronic stress significantly suppressed cytogenesis in the mPFC and neurogenesis in the dentate gyrus, but had minor effect in nonlimbic structures. Fluoxetine treatment counteracted the inhibitory effect of stress. Hemispheric comparison revealed that the rate of cytogenesis was significantly higher in the left mPFC of control animals, whereas stress inverted this asymmetry, yielding a significantly higher incidence of newborn cells in the right mPFC. Fluoxetine treatment abolished hemispheric asymmetry in both control and stressed animals. These pronounced changes in gliogenesis after chronic stress exposure may relate to the abnormalities of glial cell numbers reported in the frontolimbic areas of depressed patients.
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Teicher, M. H., Tomoda, A., & Andersen, S. L. (2006). Neurobiological Consequences of Early Stress and Childhood Maltreatment: Are Results from Human and Animal Studies Comparable? Annals of the New York Academy of Sciences, 1071(1), 313–323.
Abstract: Abstract: Recent studies have reported an association between exposure to childhood abuse or neglect and alterations in brain structure or function. One limitation of these studies is that they are correlational and do not provide evidence of a cause–effect relationship. Preclinical studies on the effects of exposure to early life stress can demonstrate causality, and can enrich our understanding of the clinical research if we hypothesize that the consequences of early abuse are predominantly mediated through the induction of stress responses. Exposure to early abuse and early stress has each been associated with the emergence of epileptiform electroencephalogram (EEG) abnormalities, alterations in corpous callosum area, and reduced volume or synaptic density of the hippocampus.Further, there is evidence that different brain regions have unique periods when they are maximally sensitive to the effects of early stress. To date, preclinical studies have guided clinical investigations and will continue to provide important insight into studies on molecular mechanisms and gene–environment interactions.
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