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Range, F., Viranyi, Z., & Huber, L. (2007). Selective Imitation in Domestic Dogs. Curr Biol, 17(10), 868–872.
Abstract: Summary The transmission of cultural knowledge requires learners to identify what relevant information to retain and selectively imitate when observing others' skills. Young human infants--without relying on language or theory of mind--already show evidence of this ability. If, for example, in a communicative context, a model demonstrates a head action instead of a more efficient hand action, infants imitate the head action only if the demonstrator had no good reason to do so, suggesting that their imitation is a selective, interpretative process [1]. Early sensitivity to ostensive-communicative cues and to the efficiency of goal-directed actions is thought to be a crucial prerequisite for such relevance-guided selective imitation [2]. Although this competence is thought to be human specific [2], here we show an analog capacity in the dog. In our experiment, subjects watched a demonstrator dog pulling a rod with the paw instead of the preferred mouth action. In the first group, using the “inefficient” action was justified by the model's carrying of a ball in her mouth, whereas in the second group, no constraints could explain the demonstrator's choice. In the first trial after observation, dogs imitated the nonpreferred action only in the second group. Consequently, dogs, like children, demonstrated inferential selective imitation.
Keywords: Sysneuro
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Martin, P., & Bateson P. (2007). Measuring Behaviour – An Introductory Guide (Third Edition). Cambridge: Cambridge University Press.
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Warneken, F., Hare, B., Melis, A. P., Hanus, D., & Tomasello, M. (2007). Spontaneous Altruism by Chimpanzees and Young Children. PLoS Biol, 5(7), e184 EP -.
Abstract: <p>Experimental evidence reveals that chimpanzees will help other unrelated humans and conspecifics without a reward, showing that they share crucial aspects of altruism with humans.</p>
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Rehage, & C. (2007). Klinische Symptomatik und Einfluss eines Nasennetzes auf die Leistung von Turnierpferden mit Headshaking. Hannover: Tierärztlichen Hochschule Hannover.
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Pfister, J. A., Stegelmeier, B. L., Cheney, C. D., & Gardner, D. R. (2007). Effect of previous locoweed (Astragalus and Oxytropis species) intoxication on conditioned taste aversions in horses and sheep. J. Anim. Sci., 85(7), 1836–1841.
Abstract: Locoweed species (Astragalus and Oxytropis spp.) are a serious toxic plant problem for grazing livestock. Horses and sheep have been conditioned to avoid eating locoweed using the aversive agent LiCl. The objective of this study was to determine if previous locoweed intoxication affects food aversion learning in horses and sheep. Horses and sheep were divided into 3 treatment groups: control (not fed locoweed and not averted to a novel feed); locoweed-novel feed averted (fed locoweed and averted to a novel feed); and averted (not fed locoweed and averted to a novel feed). Animals in the locoweed-novel feed averted groups were fed locoweed during 2 periods of 21 and 14 d, respectively, with each feeding period followed by a 14-d recovery period. Animals were averted to a novel test feed at the end of the first locoweed-feeding period, and periodically evaluated for the strength and persistence of the aversion. During the first recovery period, locoweed-novel feed averted horses ate less (9.5% of amount offered) of the test feed than did control horses (99.8%) and did not generally differ from averted horses (0%). During recovery period 2, locoweed-novel feed averted horses (4.3%) differed (P = 0.001) in consumption (% of offered) of the test feed from controls (100%) and the averted group (0%). Locoweed-novel feed averted sheep differed (P = 0.001) from controls (14.4 vs. 99.5%, respectively, during recovery period 1), whereas locoweed-novel feed averted sheep did not differ (P > 0.50) from averted sheep (0.6%). During the second recovery period, control sheep (100%) differed (P < 0.05) from averted (0%) and locoweed-novel feed averted (12.2%) groups. Two intoxicated sheep (locoweed-novel feed averted) partially extinguished the aversion during the first recovery period, but an additional dose of LiCl restored the aversion. Two of 3 intoxicated horses had strong aversions that persisted without extinction; 1 horse in the locoweed-novel feed averted group had a weaker aversion. These findings suggest that horses and sheep previously intoxicated by locoweeds can form strong and persistent aversions to a novel feed, but in some animals, those aversions may not be as strong as in animals that were never intoxicated.
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Roth, L. S. V., Balkenius, A., & Kelber, A. (2007). Colour perception in a dichromat. Journal of Experimental Biology, 210(16), 2795–2800.
Abstract: Most mammals have dichromatic colour vision based on two different types of cones: a short-wavelength-sensitive cone and a long-wavelength-sensitive cone. Comparing the signal from two cone types gives rise to a one-dimensional chromatic space when brightness is excluded. The so-called `neutral point' refers to the wavelength that the animal cannot distinguish from achromatic light such as white or grey because it stimulates both cone types equally. The question is: how do dichromats perceive their chromatic space? Do they experience a continuous scale of colours or does the neutral point divide their chromatic space into two colour categories, i.e. into colours of either short or long wavelengths?We trained horses to different colour combinations in a two-choice behavioural experiment and tested their responses to the training and test colours. The horses chose colours according to their similarity/relationship to rewarded and unrewarded training colours. There was no evidence for a categorical boundary at the neutral point or elsewhere.This study suggests that dichromats perceive their chromatic space as a continuous scale of colours, treating the colour at the neutral point as any other colour they can distinguish.
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Quaranta, A., Siniscalchi, M., & Vallortigara, G. (2007). Asymmetric tail-wagging responses by dogs to different emotive stimuli. In Current biology : CB (Vol. 17, pp. R199–R201). Cell Press.
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Carlsson, H. - E., Lyberg, K., Royo, F., & Hau, J. (2007). Quantification of stress sensitive markers in single fecal samples do not accurately predict excretion of these in the pig. Research in Veterinary Science, 82(3), 423–428.
Abstract: All feces produced during 24 h were collected from five pigs and cortisol and immunoreactive cortisol metabolites (CICM), and IgA were quantified. Within pigs, the concentrations of CICM and IgA varied extensively between random samples obtained from a single fecal dropping, and deviated in most cases significantly from the true concentration measured in total fecal output (CV 6.7–130%). The CICM and IgA contents varied considerably (CV 8.1–114%) within and between individual fecal droppings from the same pig compared to the total fecal excretion. In conclusion, single random samples could not be used to reliably quantify the total fecal concentration or excretion of CICM or IgA in pigs. Analyses of all feces collected during shorter periods than 24 h did not provide an accurate estimate of the daily excretion of CICM. Thus, the concentration of stress sensitive molecules in random single fecal samples as an indicator of animal welfare should be interpreted with prudence.
Keywords: Cortisol; Immunoglobulin A; Stress; Pigs; Feces; Animal welfare
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Paramastri, Y., Royo, F., Eberova, J., Carlsson, H. - E., Sajuthi, D., Fernstrom, A. - L., et al. (2007). Urinary and fecal immunoglobulin A, cortisol and 11-17 dioxoandrostanes, and serum cortisol in metabolic cage housed female cynomolgus monkeys (Macaca fascicularis). Journal of Medical Primatology, 36(6), 355–364.
Abstract: Background and methods Quantitative enzyme-immunoassays of urinary and fecal immunoglobulin A (IgA), cortisol and 11-17-dioxoandrostanes (11,17-DOA), and serum cortisol in eight metabolic-cage-housed female cynomolgus monkeys were performed. The monkeys were divided into two groups, B and NB. Group B animals were blood sampled every 6 hours, whereas Group NB animals were not handled/blood sampled. Results No differences were recorded between the amounts of feces and urine excreted by the two groups. Group B animals excreted more urinary cortisol than did Group NB animals indicating that restraint-blood sampling resulted in a stress response. Excreted amounts of IgA and 11,17-DOA (urine and feces) did not differ between the groups. Conclusions Urinary cortisol was a reliable marker of the stress associated with repeated blood sampling. Declining amounts of excreted urinary cortisol indicated that cynomolgus monkeys acclimated quickly to repeated blood sampling in metabolism cages. Within and between animal variation in amounts of feces voided demonstrated the importance of expressing fecal markers as ‘amounts excreted per time unit per kg body weight’ rather than just measuring the concentrations in fecal samples.
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May, A. (2007). Evaluierung von Stressparametern beim Pferd im Zusammenhang mit dem Klinikaufenthalt [Evaluation of stress parameters in the hospitalized horse]. Ph.D. thesis, LMU München, München.
Abstract: Ein Klinikaufenthalt stellt für Pferde eine Stresssituation dar und viele Pferde erkranken
während eines Klinikaufenthalts an Stress-assoziierten Erkrankungen. Eine der häufigsten ist die so genannte Colitis X, eine oft tödlich verlaufende Durchfallerkrankung. Da es im Verlauf dieser Erkrankungen zu einem Verlust der Tiere kommen kann, hat ihre Vermeidung oberste Priorität. Ziel der vorliegenden Untersuchung war es, herauszufinden, inwieweit bei den Pferden der klinisch erkennbare Stress mit Veränderungen messbarer Blutparameter (Hämatokrit, Gesamteiweiß, Leukozyten, Glukose, Laktat, Kortisol) einhergeht und dabei einen Parameter zu finden, mit dem Stress beim Klinikpatienten Pferd verlässlich und möglichst einfach evaluiert werden kann. Zudem wurden in dieser Studie Freie Sauerstoffradikale („oxidativer Stress“) und IgA im Kot bestimmt, um diese Parameter auf ihre klinische Verwendbarkeit zu prüfen und zu untersuchen, inwieweit Stress mit dem lokalen Immunglobulingehalt interferiert. Einigen ausgewählten Pferden wurde zudem der Paramunitätsinducer Zylexis® der Firma Pfizer appliziert, um dessen Wirkung auf die untersuchten Parameter festzustellen. Es wurden 110 Patienten der Klinik für Pferde untersucht, die in dem Zeitraum der Studie zufällig hospitalisiert wurden. Die Pferde wurden in zwei Gruppen eingeteilt. Eine Gruppe wurde in der Klinik operiert, die zweite nur stationär behandelt. Des Weiteren wurde eine Kontrollgruppe in ihrem Heimatstall zum Vergleich miteinbezogen, die in den letzten sechs Wochen vor der Studie nicht transportiert oder anderweitig belastet worden war. Den Pferden wurde in definierten Abständen Blut und Kot entnommen, um den Einfluss von Transport, Operation und Klinikstress möglichst gut zu erfassen. Die Zeitpunkte waren direkt nach der Einlieferung, am Morgen vor der Narkose, nach der Aufstehphase und sowohl einen als auch vier Tage nach der Narkose. Pferden, die nicht operiert wurden und der Kontrollgruppe wurden insgesamt dreimal Blut und Kot (Tag 1, 3, Tag vor der Entlassung) entnommen. Für die Zylexis®-Studie wurden Vitrektomie-Patienten ausgewählt, da diese ein gutes Beispiel für eine kurze, wenig traumatische Operation darstellen. Diese Pferde wurden mit den anderen Pferden, die leichten Operationen unterzogen wurden, verglichen. Bereits nach dem unterschiedlich langen Transport zeigten die Pferde signifikante Anstiege von Gesamtleukozytenzahl, dem Verhältnis neutrophiler Granulozyten zu Lymphozyten (N:L-Verhältnis), Glukose und den klinischen Parametern (Herzfrequenz, Atemfrequenz, Körpertemperatur). Die IgA-Konzentration im Kot sank bei den eingelieferten Pferden nach Einlieferung erst ab, um sich dann vermutlich durch den Kontakt mit den fremden Antigenen in der Klinik reflektorisch zu erhöhen. Auffällig war, dass die Kortisolkonzentration nach dem Transport bei den als „nervös, sensibel“ eingestuften Pferden signifikant höher lag als bei den „ruhigen, ausgeglichenen“ Pferden. Weitere deutliche Veränderungen zeigten sich nach den Operationen. Glukose, Kortisol und das N:L-Verhältnis wiesen nach den unterschiedlich langen Eingriffen höhere Konzentrationen auf. Die Laktatkonzentration stieg signifikant bereits nach der Operation und anschließend noch weiter nach der Aufstehphase. Dies ist primär auf die Muskelbelastung zurückzuführen, da Laktat vor allem muskulären Ursprungs ist. Hämatokrit und Gesamteiweiß sanken nach der Narkose aufgrund der intraoperativ verabreichten Infusionen ab. Einem starken hoch signifikanten Konzentrationsabfall unterlag auch der IgA-Gehalt im Kot. Dabei war kein Unterschied zwischen den verschiedenen Operationstraumata festzustellen. Ansonsten unterlagen die Pferde, die mit hochgradig gestörtem Allgemeinbefinden zu einer Notoperation eingeliefert wurden, viel deutlicheren Veränderungen als die anderen Pferde. Die Freien Radikale zeigten überhaupt keinen charakteristischen Verlauf. Sie schienen allerdings bei den chronisch erkrankten Pferden erhöht zu sein. Des Weiteren zeigten sie Erhöhungen bei bestimmten Erkrankungen („Equine Motor Neuron Disease“, Hufrehe). Bei den Pferden, die Zylexis® verabreicht bekamen, konnte eine Tendenz zur Verbesserung des Immunstatus nachgewiesen werden. Es fiel ein deutlich höherer Gesamteiweißgehalt auf, der wahrscheinlich auf eine vermehrte Produktion von Immunglobulinen zurückzuführen ist. Außerdem war die Kortisolkonzentration nach der Operation signifikant niedriger. Der IgAGehalt zeigte einen weniger deutlichen Konzentrationsabfall, was aber statistisch nicht belegt werden konnte. Die Untersuchungen zeigten, dass das N:L-Verhältnis und Glukose geeignete Parameter darstellen um zuverlässig den Stress, dem ein Pferd ausgesetzt ist, zu evaluieren. Kortisol ist vorsichtig zu interpretieren, da es großen individuellen Schwankungen ausgesetzt ist. Die Bestimmung von IgA im Kot gibt Aufschluss über den lokalen Immunstatus des Intestinaltrakts. Da es bei allen Pferden postoperativ zu signifikanten Konzentrationsabfällen kam, sind Pferde nach jeder Operation offensichtlich prädisponiert, eine Darmerkrankung, wie beispielsweise Colitis X, zu entwickeln. Kortisol scheint auch Einfluss auf das lokale Immunsystem zu nehmen, da hohe Kortisolwerte mit einem niedrigen IgA-Gehalt im Kot korrelierten. Um die Zusammenhänge der Blutparameter und der Colitis X näher zu erforschen und insbesondere um die „kritischen“ IgA-Konzentrationen zu ermitteln, wären noch weiterführende Untersuchungen aufschlußreich. [Many horses in clinics display symptoms of stress-associated diseases. One of the most feared is the so-called Colitis X, an often fatal ending diarrhea. As death occurs quite often in the course of those diseases, their avoidance has first priority. The aim of the following study was to find out whether signs of stress which are displayed by the horses correlate with measurable blood parameters. Furthermore we tried to find a parameter which was suitable to evaluate stress in hospitalized horses. Apart from the commonly measured parameters (hematocrit, total protein, leucocytes, glucose, lactate, corticosterone) we tried to include free oxygen radicals in this study. Immunoglobulin A in faeces was investigated to find out how stress interfered with the local immune system. A Paramunityinducer often used in Germany (Zylexis®) was administered to 10 selected horses to research its effect on the different parameters. 110 patients hospitalized in the horse clinic were examined. First the horses were organized into two groups. One group underwent surgery and the other one received stationary treatment. Furthermore a control group was taken into account which had not been transported or subjected to stress in six weeks prior to the study. The horses were drawn blood and collected faeces in defined intervals to register the influence of transport, operation and clinic stress. Blood samples were taken directly after the transport, prior to the operation, right after surgery and one day and four days after the operation. Horses which did not undergo surgery including the control group were drawn blood and faeces three times (day 1, 3, and the day prior to discharge from the clinic). For the paramunity investigation patients for vitrectomy were chosen as they display a good example for short little traumatic operations. Those were compared with other horses brought into the clinic for short operations. After the transport to the clinic horses showed significant increases in leukocyte concentration, N:L-ratio, glucose and the clinical parameters (heart rate, breathing rate, body temperature). The immunoglobulin concentration decreased after the transport to rapidly rise after contact with antigens from the clinic environment. Horses categorized as “nervous, sensitive” displayed significantly higher corticosterone concentrations after the transport than horses categorized as “cool, calm”. Other distinct variations showed after the operations. The lactate concentrations increased significantly after anaesthesia and went up even further after the horse got up afterwards. This is due to muscular fatigue as lactate is mainly produced in the muscles. Glucose, corticosterone and the N:L-ratio also displayed higher concentrations after the operation. Hematocrit and total protein concentrations decreased after anaesthesia ascribed to infusions during operation. After anaesthesia a highly significant reduction of immunoglobulin concentrations in the faeces was determined. No influence of the different operation traumas could be recognized. That was surprising as in all other cases horses in very bad general condition displayed distinct changes. The free oxygen radicals did not show any characteristic pattern. There appeared to be a higher concentration in horses with chronic illnesses. Furthermore some diseases, like Equine Motor Neuron Disease and laminitis, seemed to have an increasing impact on the oxygen radicals. Zylexis® showed a tendency to improve the immune status of the horses in this study. The paramunized horses had more total serum protein than the others. This could be due to an increased production of Immunoglobulins. Additionally the corticosterone concentration after the operation stayed on a significantly lower level. The local immunoglobulin A concentrations did not appear to decrease as much as in the non-paramunized horses but it was not possible to statistically prove this statement. The results of this study show that the N:L-ratio and glucose might be suitable parameters to reliably evaluate the stress that has an effect on the hospitalized horse. Corticosterone values have to be interpreted carefully as they are very prone to individual variations. Measuring immunoglobulins in faeces provides information about the local intestinal immune status. Since all horses showed significant lower immunoglobulin concentrations after the anesthesia/operation they obviously lack immune protection and are therefore predisposed for developing enteritis, as Colitis X. In this study corticosterone seemed to influence the local immune system as high concentrations of corticosterone correlated with low immunoglobulin levels. To understand the circumstances more thoroughly and to find out which factors have to be present additionally in order for the horses to fall ill with Colitis X, further investigations have to be made.] |