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Dreschel, N. A., & Granger, D. A. (2009). Methods of collection for salivary cortisol measurement in dogs. Horm. Behav., 55(1), 163–168.
Abstract: Salivary cortisol has been increasingly used as a measure of stress response in studies of welfare, reaction to stress and human–animal interactions in dogs and other species. While it can be a very useful measure, there are a number of saliva collection issues made evident through studies in the human and animal fields which have not been investigated in the canine species. Collection materials and the volume of saliva that is collected; the use of salivary stimulants; and the effect of food contamination can all dramatically impact cortisol measurement, leading to spurious results. In order to further examine the limitations of the collection method and the effects of collection material and salivary stimulant on salivary cortisol levels, a series of clinical, in vitro and in vivo studies were performed. It was found that there is a large amount of inter- and intra-individual variation in salivary cortisol measurement. Beef flavoring of collection materials leads to unpredictable variability in salivary cortisol concentration. Using salivary stimulants such as citric acid also has the potential to affect cortisol concentration measurement in saliva. Hydrocellulose appears to be a useful collection material for salivary cortisol determination. Recommendations for collection materials and use of salivary stimulants are presented.
Keywords: Dog; Canine; Salivary cortisol; Methods; Measurement; Stress
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Dickens, M. J., Delehanty, D. J., & Romero, L. M. (2009). Stress and translocation: alterations in the stress physiology of translocated birds. Proceedings of the Royal Society B: Biological Sciences, 276(1664), 2051–2056.
Abstract: Translocation and reintroduction have become major conservation actions in attempts to create self-sustaining wild populations of threatened species. However, avian translocations have a high failure rate and causes for failure are poorly understood. While ‘stress’ is often cited as an important factor in translocation failure, empirical evidence of physiological stress is lacking. Here we show that experimental translocation leads to changes in the physiological stress response in chukar partridge, Alectoris chukar. We found that capture alone significantly decreased the acute glucocorticoid (corticosterone, CORT) response, but adding exposure to captivity and transport further altered the stress response axis (the hypothalamic–pituitary–adrenal axis) as evident from a decreased sensitivity of the negative feedback system. Animals that were exposed to the entire translocation procedure, in addition to the reduced acute stress response and disrupted negative feedback, had significantly lower baseline CORT concentrations and significantly reduced body weight. These data indicate that translocation alters stress physiology and that chronic stress is potentially a major factor in translocation failure. Under current practices, the restoration of threatened species through translocation may unwittingly depend on the success of chronically stressed individuals. This conclusion emphasizes the need for understanding and alleviating translocation-induced chronic stress in order to use most effectively this important conservation tool.
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Romero, L. M., Dickens, M. J., & Cyr, N. E. (2009). The reactive scope model — A new model integrating homeostasis, allostasis, and stress. Horm. Behav., 55(3), 375–389.
Abstract: Allostasis, the concept of maintaining stability through change, has been proposed as a term and a model to replace the ambiguous term of stress, the concept of adequately or inadequately coping with threatening or unpredictable environmental stimuli. However, both the term allostasis and its underlying model have generated criticism. Here we propose the Reactive Scope Model, an alternate graphical model that builds on the strengths of allostasis and traditional concepts of stress yet addresses many of the criticisms. The basic model proposes divergent effects in four ranges for the concentrations or levels of various physiological mediators involved in responding to stress. (1) Predictive Homeostasis is the range encompassing circadian and seasonal variation — the concentrations/levels needed to respond to predictable environmental changes. (2) Reactive Homeostasis is the range of the mediator needed to respond to unpredictable or threatening environmental changes. Together, Predictive and Reactive Homeostasis comprise the normal reactive scope of the mediator for that individual. Concentrations/levels above the Reactive Homeostasis range is (3) Homeostatic Overload, and concentrations/levels below the Predictive Homeostasis range is (4) Homeostatic Failure. These two ranges represent concentrations/levels with pathological effects and are not compatible with long-term (Homeostatic Overload) or short-term (Homeostatic Failure) health. Wear and tear is the concept that there is a cost to maintaining physiological systems in the Reactive Homeostasis range, so that over time these systems gradually lose their ability to counteract threatening and unpredictable stimuli. Wear and tear can be modeled by a decrease in the threshold between Reactive Homeostasis and Homeostatic Overload, i.e. a decrease in reactive scope. This basic model can then be modified by altering the threshold between Reactive Homeostasis and Homeostatic Overload to help understand how an individual's response to environmental stressors can differ depending upon factors such as prior stressors, dominance status, and early life experience. We illustrate the benefits of the Reactive Scope Model and contrast it with the traditional model and with allostasis in the context of chronic malnutrition, changes in social status, and changes in stress responses due to early life experiences. The Reactive Scope Model, as an extension of allostasis, should be useful to both biomedical researchers studying laboratory animals and humans, as well as ecologists studying stress in free-living animals.
Keywords: Stress; Allostasis; Glucocorticoids; Fight-or-flight; Homeostasis
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Warneken, F., & Tomasello, M. (2009). Varieties of altruism in children and chimpanzees. In Trends in cognitive sciences (Vol. 13, pp. 397–402). Elsevier Science,.
Abstract: Recent empirical research has shed new light on the perennial question of human altruism. A number of recent studies suggest that from very early in ontogeny young children have a biological predisposition to help others achieve their goals, to share resources with others and to inform others of things helpfully. Humans nearest primate relatives, such as chimpanzees, engage in some but not all of these behaviors: they help others instrumentally, but they are not so inclined to share resources altruistically and they do not inform others of things helpfully. The evolutionary roots of human altruism thus appear to be much more complex than previously supposed.
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Goodson, J. L., Schrock, S. E., Klatt, J. D., Kabelik, D., & Kingsbury, M. A. (2009). Mesotocin and Nonapeptide Receptors Promote Estrildid Flocking Behavior. Science, 325(5942), 862–866.
Abstract: Proximate neural mechanisms that influence preferences for groups of a given size are almost wholly unknown. In the highly gregarious zebra finch (Estrildidae: Taeniopygia guttata), blockade of nonapeptide receptors by an oxytocin (OT) antagonist significantly reduced time spent with large groups and familiar social partners independent of time spent in social contact. Opposing effects were produced by central infusions of mesotocin (MT, avian homolog of OT). Most drug effects appeared to be female-specific. Across five estrildid finch species, species-typical group size correlates with nonapeptide receptor distributions in the lateral septum, and sociality in female zebra finches was reduced by OT antagonist infusions into the septum but not a control area. We propose that titration of sociality by MT represents a phylogenetically deep framework for the evolution of OT’s female-specific roles in pair bonding and maternal functions.
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Hoffmann, G., Bockisch, F. - J., & Kreimeier, P. (2009). Einfluss des Haltungssystems auf die Bewegungsaktivität und Stressbelastung bei Pferden in Auslaufhaltungssystemen. Landbauforschung – vTI Agriculture and Forestry Research, 2(59), 105–112.
Abstract: Frühere Untersuchungen haben gezeigt, dass die tägliche Bewegung für die Gesunderhaltung der Pferde notwendig ist. Inwieweit sich jedoch unterschiedliche Bewegungsangebote auf das Stress-und Bewegungsverhalten von Pferden in einer Gruppen-Auslaufhaltung auswirken und ob der Bewegungsbedarf der Pferde durch eine Auslaufhaltung ohne zusätzliche Bewegung gedeckt werden kann, ist der Literatur bisher nicht zu entnehmen. Daher sollte in der nachfolgend beschriebenen Untersuchung der Frage nachgegangen werden, welche Auswirkungen verschiedene Bewegungsangebote auf die Bewegungsaktivität von Pferden in Gruppen-Auslaufhaltungen haben und ob diese das Wohlbefinden der Tiere beeinflussen. Letzteres wurde durch Messung der Herzfrequenzvariabilität und Bestimmung von Cortisolmetaboliten im Pferdekot erfasst und die Bewegungsaktivität der Pferde wurde mit ALT-Pedometern bestimmt.
Verglichen wurden eine Einzel-und Gruppenhaltung mit jeweils angrenzendem Auslauf, aber ohne eine zusätzliche Bewegung der Pferde außerhalb des Stalls. In drei weiteren Varianten der Gruppenhaltung bekamen die Pferde täglichen Auslauf auf einer unbegrünten Koppel, auf einer Weide oder durch gezielte Bewegung in einer Führanlage. Die Bewegungsaktivität konnte durch die zusätzliche Bewegung in Form von Weide oder Führanlage signifikant gesteigert werden. Ein zusätzliches Bewegungsangebot führte bei den Pferden zu einer Abnahme der Stressbelastung und sollte auch den Pferden ermöglicht werden, die in einer Gruppenhaltung gehalten werden, um ihre physische und psychische Gesundheit zu erhalten. [Former studies confirm the necessity of daily movement for the health of a horse. But so far no description could be found in the literature how different movement offerings impact the stress and movement behaviour of horses in group husbandries with close-by discharge. The same holds true for the question whether a discharge husbandry system can meet the movement requirements of horses if there isn�t any additional movement possibility. The aim of the present study was to examine different movement offerings, their effects on the movement activities of horses in a group horse husbandry with close-by discharge and the impact of the movement on the wellbeing of the animals. The heart rate variability and the concentration of the cortisol metabolites in the horse excrement were analyzed for detecting the wellbeing of the horses. Additionally ALT-Pedometers were used for determining the movement activity. A single and a group husbandry system, each with closeby discharge, were compared when horses had no additional movement outside the stable. In three further variants the group husbandry was supplemented with daily time on a non-grassy pasture land, a pasture or in a horse walker. Pasture or horse walker increased movement activity significantly. Nevertheless an additional movement offering resulted in a lower stress load of the horses and should also be allowed to horses in group husbandry systems to ensure the horse�s physical and mental health.] |
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Krueger, K., & Flauger, B. (2009). Horses (Equus caballus) show respect and trust in their owners. In P. M. Kappeler, & M. Schwibbe (Eds.), Program of the 4. Thementagung der Ethologischen Gesellschaft, Februar 12 -14, 2009. (32). Göttingen: Dpz.
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Hausberger, M., Gautier, E., Biquand, V., Lunel, C., & Jégo, P. (2009). Could Work Be a Source of Behavioural Disorders? A Study in Horses. PLoS ONE, 4(10), e7625 EP -.
Abstract: <p>Stress at work, as shown by a number of human studies, may lead to a variety of negative and durable effects, such as impaired psychological functioning (anxiety, depression…). Horses share with humans this characteristic of working on a daily basis and are submitted then to work stressors related to physical constraints and/or more “psychological” conflicts, such as potential controversial orders from the riders or the requirement to suppress emotions. On another hand, horses may perform abnormal repetitive behaviour (“stereotypies”) in response to adverse life conditions. In the present study, we investigated whether the type of work the horses are used for may have an impact on their tendency to show stereotypic behaviour (and its type) outside work. Observations in their box of 76 horses all living in the same conditions, belonging to one breed and one sex, revealed that the prevalence and types of stereotypies performed strongly depended upon the type of work they were used for. The stereotypies observed involved mostly mouth movements and head tossing/nodding. Work constraints probably added to unfavourable living conditions, favouring the emergence of chronic abnormal behaviours. This is especially remarkable as the 23 hours spent in the box were influenced by the one hour work performed every day. To our knowledge, this is the first evidence of potential effects of work stressors on the emergence of abnormal behaviours in an animal species. It raises an important line of thought on the chronic impact of the work situation on the daily life of individuals.</p>
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Flauger, B., Krueger, K., Gerhards, H., & Moestl, E. (2009). Measurement of glucocorticoid metabolites in horse faeces: the validation of different group specific enzymeimmunoassays and extraction methods. In S. Cremer, A. Schrempf, & J. Heinze (Eds.), Proceeding of the 102. Annual meeting of the Deutsche Zoologische Gesellschaft (DZG). (166). München: Dt. Zoologische Ges.
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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. |