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Morton, F. B., Lee, P. C., & Buchanan-Smith, H. M. (2013). Taking personality selection bias seriously in animal cognition research: a case study in capuchin monkeys (Sapajus apella). Animal Cognition, 16(4), 677–684.
Abstract: In most experimental work on animal cognition, researchers attempt to control for multiple interacting variables by training subjects prior to testing, allowing subjects to participate voluntarily, and providing subjects with food rewards. However, do such methods encourage selection bias from subjects’ personalities? In this study, we trained eighteen zoo-housed capuchin monkeys (Sapajus apella) for two experiments, under conditions of positive reinforcement (i.e. food rewards) and free-choice participation. Using a combination of behavioral and rater-based methods, we identified and validated five personality dimensions in these capuchins (Assertiveness, Openness, Neuroticism, Sociability, and Attentiveness). Scores on Openness were positively related to individual differences in monkey task participation, reflecting previous work showing that such individuals are often more active, curious, and willing to engage in testing. We also found a negative relationship between scores on Assertiveness and performance on tasks, which may reflect the trade-offs between speed and accuracy in these animals’ decision-making. Highly Assertive individuals (the most sociable within monkey groups) may also prioritize social interactions over engaging in research. Lastly, monkeys that consistently participated and performed well on both tasks showed significantly higher Openness and lower Assertiveness compared to others, mirroring relationships found between personality, participation, and performance among all participants. Participation and performance during training was clearly biased toward individuals with particular personalities (i.e. high Openness, low Assertiveness). Results are discussed in light of the need for careful interpretation of comparative data on animal cognition and the need for researchers to take personality selection bias more seriously.
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Guttridge, T. L., Dijk, S., Stamhuis, E. J., Krause, J., Gruber, S. H., & Brown, C. (2013). Social learning in juvenile lemon sharks, Negaprion brevirostris. Animal Cognition, 16(1), 55–64.
Abstract: Social learning is taxonomically widespread and can provide distinct behavioural advantages, such as in finding food or avoiding predators more efficiently. Although extensively studied in bony fishes, no such empirical evidence exists for cartilaginous fishes. Our aim in this study was to experimentally investigate the social learning capabilities of juvenile lemon sharks, Negaprion brevirostris. We designed a novel food task, where sharks were required to enter a start zone and subsequently make physical contact with a target in order to receive a food reward. Naive sharks were then able to interact with and observe (a) pre-trained sharks, that is, ‘demonstrators’, or (b) sharks with no previous experience, that is, ‘sham demonstrators’. On completion, observer sharks were then isolated and tested individually in a similar task. During the exposure phase observers paired with ‘demonstrator’ sharks performed a greater number of task-related behaviours and made significantly more transitions from the start zone to the target, than observers paired with ‘sham demonstrators’. When tested in isolation, observers previously paired with ‘demonstrator’ sharks completed a greater number of trials and made contact with the target significantly more often than observers previously paired with ‘sham demonstrators’. Such experience also tended to result in faster overall task performance. These results indicate that juvenile lemon sharks, like numerous other animals, are capable of using socially derived information to learn about novel features in their environment. The results likely have important implications for behavioural processes, ecotourism and fisheries.
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Schnerr, C. U. (2011). Feldstudie zur Epidemiologie und Bekämpfung von Strongyliden in Pferdebeständen im Raum Baden- Württemberg. Ph.D. thesis, , .
Abstract: In der Zeit von April 2005 bis März 2006 wurden bei 105 Pferden monatlich
koprologische Untersuchungen durchgeführt. Die Pferde waren zu zwei Drittel Jungtiere (≤ 4 Jahre) und ein Drittel > 4 Jahre. Die zur Verfügung stehenden vier Betriebe befanden sich alle im Raum Baden-Württemberg. Die Kotproben wurden mit Hilfe der Flotation auf Magen-Darmnematoden untersucht und anschließend einer quantitativen Eizahlbestimmung nach Mc Master unterzogen. Ab einem Eigehalt von 250 Eiern pro Gramm Kot (EpG) wurden die Pferde entsprechend der Gruppenzugehörigkeit entweder mit Pyrantel oder Ivermectin behandelt. Es wurden bei 73 Pferden ausschließlich Strongylideneier nachgewiesen; bei vier Pferden waren in der Flotation zusätzlich Eier von Parascaris equorum zu finden. Bei 28 (26,7%) der untersuchten Pferde wurden in keiner der 12 untersuchten Proben Eier von Magen-Darmnematoden nachgewiesen. Insgesamt mussten 57 (54,3%) der Pferde über den gesamten Untersuchungszeitraum hinweg nicht behandelt werden. 48 (45,7%) Pferde mussten mindestens einmal anthelminthisch behandelt werden. Kein Pferd musste häufiger als dreimal behandelt werden. In den Monaten August bis November war der Anteil an positiven Proben der Jungtiere signifikant höher als bei den Pferden > 4 Jahre. Innerhalb der Jungtiergruppe nahm die Höhe der Strongyliden-Eiausscheidung mit zunehmendem Alter signifikant ab. Ebenso nahm die Anzahl der positiven Proben im Laufe des Untersuchungszeitraums signifikant ab. Die beiden zur Entwurmung eingesetzten Substanzen (Pyrantel und Ivermectin) waren voll wirksam. In 98,8% der untersuchten Proben war ein Rückgang der Ei-Ausscheidung noch vier Wochen nach der Behandlung auf 0 EpG nachweisbar, d. h. es gab keinerlei Anzeichen für das Vorliegen von Resistenzen gegen die eingesetzten Substanzen. Die vorliegenden Untersuchungen sind ein weiterer Beweis dafür, dass mit Hilfe der selektiven anthelminthischen Behandlung die Anzahl der Entwurmungen – insbesondere auch bei Jungtieren – deutlich gesenkt werden kann. Die Eiausscheidung und damit die Weidekontamination werden mit Hilfe dieses Verfahrens deutlich reduziert. [Between April 2005 and March 2006 monthly koprological examinations where carried out on 105 horses. Two third of the horses were young animals (≤ 4 years) and a third were > 4 years old. The four farms on hand were all located in the Baden- Württemberg area. Faecal samples were examined for gastro-intestinal nematodes by means of flotation and subsequently subjected to an egg-quantity counting according to Mc Master. Starting from an egg content of 250 eggs per gram faeces (EpG), the horses were treated with either Pyrantel or Ivermectin according to their group affiliation. In 73 horses solely Strongyle eggs were detected; the flotation of four horses additionaly showed eggs of Parascaris equorum. In 28 (26,7%) of the examined horses none of the 12 examined samples showed eggs of gastro-intestinal nematodes. Overall 57 (54,3%) horses didn´t need any treatment during the total examination cycle. 48 (45,7%) of the horses needed at least one anthelminthic treatment. None of the horses needed to be treated more than three times. From August to November the rate of positive samples within the group of young animals was significantly higher than in the horses > 4 years. Whithin the group of young animals the level of Strongyle egg excretions dropped significantly with advancing age. Likewise, the number of positive samples also dropped significantly in the course of the examination cycle. Both substances (Pyrantel and Ivermectin) applied for deworming were fully effective. Even a further 4 weeks after treatment the examined sample showed a drop of egg excretion to 0 EpG in 98,8% of the samples, in other words there were no signs of prevailing resistance appearances towards the applied substance. The present studies are further proof that the number of dewormings-especially in young animals can be distinctly reduced by means of selective anthelminthic treatments. Egg excretion and therewith pasture land contamination can be clearly reduced by means of this procedure.] |
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Fabritius, C. (2009). Sozialstruktur einer Herde Islandpferde bei Veränderung der Gruppenzusammenstellung. Ph.D. thesis, , Hannover.
Abstract: Die Domestikation des Pferdes begann wahrscheinlich etwa 5500 v. Chr. in
Südosteuropa. In Mitteleuropa traten circa 3000 v. Chr. die ersten Hauspferde auf. Grundsätzlich wird davon ausgegangen, dass sich die Ansprüche des Pferdes hinsichtlich der Lebensbedingungen, welche sich im Laufe der Evolution über Millionen von Jahren entwickelt haben, in der Obhut des Menschen nicht wesentlich geändert haben. Für Pferde typisch ist das Leben im Sozialverband, der Herde (Zeitler-Feicht 2008). Diese wird auch in den Leitlinien der Sachverständigengruppe tierschutzgerechte Pferdehaltung (10. November 1995) empfohlen, sofern es nicht durch zu häufigen Wechsel im Bestand zu einem Übermaß an Stress und agonistischen Aktionen kommt. Ziel der Arbeit war es, anhand eines nach der Literatur erstellten Ethogramms des Sozialverhaltens des Pferdes, herauszufinden, inwieweit Änderungen der Gruppenstruktur die sozialen Beziehungen beeinflussten. Die Fragestellung bezog sich auf eine Herde in Offenstallhaltung. Um die eventuellen Veränderungen der sozialen Interaktionen zu untersuchen, wurde erst die vorhandene Gruppenstruktur der Herde festgestellt. Danach wurde ein Individuum aus der Herde entfernt und ein anderes dazugestellt. Anschließend wurde die Gesamtgruppe in zwei Untergruppen geteilt und nach einem gewissen Zeitraum erneut zusammengeführt. Dabei wurden jeweils die Interaktionen der Pferde anhand des Ethogramms beobachtet, aufgezeichnet und protokolliert. Untersuchungsgegenstand war eine Herde Islandpferde, die in einer Ausgangsgruppe von 16 Tieren gehalten wurde. Die Beschreibung einer sozialen Ordnung im Allgemeinen und einer Rangordnung im Besonderen wird in vielen Studien ausschließlich auf der Basis der Beobachtung und Bewertung offensiv aggressiver Verhaltenselemente durchgeführt. Aggressives Verhalten muss hingegen im Gegensatz zu Verhaltensweisen, die die Anerkennung des sozialen Status des anderen Pferdes bedeuten, wie Abwenden oder Meiden, nicht notwendigerweise ein Anzeichen von Dominanz über ein anderes Tier bedeuten (Van Hoof u. Wensing 1987, Schilder 1988). Ein weiterer Aspekt dieser Arbeit sollte sein, eine Möglichkeit zu finden, die Sozialstruktur auch auf der Grundlage defensiver und soziopositiver Verhaltenselemente zu definieren. |
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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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Asa, C. S. (1999). Male reproductive success in free-ranging feral horses. Behavioral Ecology and Sociobiology, 47(1-2), 89–93.
Abstract: In the social organization of feral horses, adult males compete to monopolize groups or bands of females, sometimes called harems. Alternative male strategies are to remain alone or with other bachelors or, less commonly, to accept subordinate status within a harem. The hypothesis that dominant harem stallion status confers a reproductive advantage was tested in free-ranging feral horses. The presence of foals in harems headed by vasectomized (VSX) versus intact stallions was used to assess the ability of these stallions to control reproduction in their harems. Of harems headed by VSX stallions, 17 and 33% contained foals during years 2 and 3 post-treatment, respectively. In contrast, 86 and 80% of harems headed by non-VSX stallions contained foals in those years. Acquisition of pregnant mares appeared more likely than sneak copulations by bachelor stallions to account for foals in harems with a single stallion. However, most foals were born into harems that included a subordinate stallion, an occurrence that was undoubtedly exacerbated by the extended breeding season resulting from the sterility of the harem stallion. Thus, in comparing alternative reproductive tactics, bachelors appeared less successful than subordinate stallions within a harem. However, the highest reproductive success was achieved by the harem stallion, further demonstrating that alternative tactics are not equally profitable.
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Slater, P., Rosenblatt, J., Snowdon, C., & Roper, T. (2004). Advances In The Study Of Behavior, 34.34.
Abstract: DescriptionThe aim of Advances in the Study of Behavior remains as it has been since the series began: to serve the increasing number of scientists who are engaged in the study of animal behavior by presenting their theoretical ideas and research to their colleagues and to those in neighboring fields. We hope that the series will continue its “contribution to the development of the field”, as its intended role was phrased in the Preface to the first volume in 1965. Since that time, traditional areas of animal behavior have achieved new vigor by the links they have formed with related fields and by the closer relationship that now exists between those studying animal and human subjects. Advances in the Study of Behavior, Volume 31 continues to serve scientists across a wide spectrum of disciplines. Focusing on new theories and research developments with respect to behavioral ecology, evolutionary biology, and comparative psychology, these volumes foster cooperation and communications in these dense fields.AudienceExperimental psychologists studying animal behavior, comparative psychologists, ethologists, evolutionary biologists, and ichthyologists.ContentsContributors. Preface.M.L. East and H. Hofer, Conflict and Co-operation in a Female Dominated Society: A Re-assessment of the “Hyper-aggressive” Image of Spotted Hyenas.C. ten Cate, H. Slabbekoorn, and M.R. Ballintijn, Bird Song and Male-male Competition: Causes and Consequences of Vocal Variability in the Collared Dove (Streptopelia Decaocto).R.W. Byrne, Imitation of Novel Complex Actions: What Does the Evidence from Animals Mean?L.J. Rogers, Lateralization in Vertebrates: Its Early Evolution, General Pattern and Development.S.H. Hulse, Auditory Scene Analysis in Animal Communication.P.K. Stoddard, Electric Signals: Predation, Sex, and Environmental Constraints.T. Aubin and P. Jouventin, How to Vocally Identify Kin in a Crowd: The Penguin Model. Index. Contents of Previous Volumes.
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Wynne C. D. L. (2001). Animal Cognition: The Mental Lives of Animals. Palgrave.
Abstract: Covering a wide range of key topics, from reasoning and communication to sensation and complex problem-solving, this engagingly-written text presents a comprehensive survey of contemporary research on animal cognition. Written for anyone with an interest in animal cognition, but without a background in animal behaviour, it endeavours to explain what makes animals tick.
With numerous illustrations and including exciting recent studies from many little-studied species (such as the weakly electric African fish), this text is ideal for psychology students who are interested in how much of our human cognition is shared by other species, for students of biology who want to know how complex animal behaviour can get, and for all those with an interest in the animal mind. |
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Arnold, C., Krüger, K., & Bojer, M. (2020). Die Wirkung von Yoga auf Reiterinnen. Wald: Xenophon Verlag.
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Sighieri, C., Tedeschi, D., De Andreis, C., Petri, L., & Baragli, P. (2003). Behaviour Patterns of Horses Can be Used to Establish a Dominant-Subordinate Relationship Between Man and Horse. Animal Welfare, 12(4), 705–708.
Abstract: This paper describes how man can enter the social hierarchy of the horse by mimicking the behaviour and stance it uses to establish dominance. A herd is organised according to a dominance hierarchy established by means of ritualised conflict. Dominance relationships are formed through these confrontations: one horse gains the dominant role and others identify themselves as subordinates. This study was conducted using five females of the Haflinger breed, totally unaccustomed to human contact, from a free-range breeding farm. The study methods were based on the three elements fundamental to the equilibrium of the herd: flight, herd instinct and hierarchy. The trainer-horse relationship was established in three phases: retreat, approach and association. At the end of the training sessions, all of the horses were able to respond correctly to the trainer. These observations suggest that it is possible to manage unhandled horses without coercion by mimicking their behaviour patterns.
Keywords: animal welfare; behaviour patterns; dominance; unhandled horse
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