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Harrison, S. A., & Tong, F. (2009). Decoding reveals the contents of visual working memory in early visual areas. Nature, 458(7238), 632–635.
Abstract: Visual working memory provides an essential link between perception and higher cognitive functions, allowing for the active maintenance of information about stimuli no longer in view1, 2. Research suggests that sustained activity in higher-order prefrontal, parietal, inferotemporal and lateral occipital areas supports visual maintenance3, 4, 5, 6, 7, 8, 9, 10, 11, and may account for the limited capacity of working memory to hold up to 3–4 items9, 10, 11. Because higher-order areas lack the visual selectivity of early sensory areas, it has remained unclear how observers can remember specific visual features, such as the precise orientation of a grating, with minimal decay in performance over delays of many seconds12. One proposal is that sensory areas serve to maintain fine-tuned feature information13, but early visual areas show little to no sustained activity over prolonged delays14, 15, 16. Here we show that orientations held in working memory can be decoded from activity patterns in the human visual cortex, even when overall levels of activity are low. Using functional magnetic resonance imaging and pattern classification methods, we found that activity patterns in visual areas V1–V4 could predict which of two oriented gratings was held in memory with mean accuracy levels upwards of 80%, even in participants whose activity fell to baseline levels after a prolonged delay. These orientation-selective activity patterns were sustained throughout the delay period, evident in individual visual areas, and similar to the responses evoked by unattended, task-irrelevant gratings. Our results demonstrate that early visual areas can retain specific information about visual features held in working memory, over periods of many seconds when no physical stimulus is present.
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Hartmann, E., Christensen, J. W., & Keeling, L. J. (2009). Social interactions of unfamiliar horses during paired encounters: Effect of pre-exposure on aggression level and so risk of injury. Appl. Anim. Behav. Sci., 121(3-4), 214–221.
Abstract: Group housing of horses is not widely applied in practice despite the welfare advantages of keeping animals socially rather than individually. In particular, concerns have been raised about the possible increased risk of injury and how to introduce a new horse into an established group. This study investigated two hypotheses: (1) pre-exposure of young horses in neighbouring boxes reduces the frequency of aggressive interactions when the same horses are subsequently put together in a paddock compared to horses without this previous box experience, (2) the occurrence of aggressive behaviour, in particular contact aggression in the paddock can be predicted after observing the horses' social interactions in neighbouring boxes. Danish Warmblood mares (n = 20), 2 years old, were kept in two groups of 10 horses. In total, 60 encounters were arranged whereby each horse was confronted pair-wise with six horses from the other group, three according to each treatment: treatment I--box (B) and subsequent paddock meeting (BP), and treatment II--only paddock meeting (P). Horses met in neighbouring boxes for 5 min and together in the same paddock for 10 min. The frequencies of aggressive and non-aggressive interactions were analysed from video recordings. Total aggression levels between BP and P did not differ, but [`]contact aggression', i.e. bite, kick, strike, push, tended to be lower in BP compared to P (median BP = 1, P = 2; p = 0.083) and there were less bites in BP than P (median BP = 0, P = 1; p = 0.050). Frequencies of [`]non-aggressive' interactions, e.g. friendly approach, nasal sniff, were lower in BP than P (median BP = 2.5, P = 10; p < 0.01). Results further revealed that [`]bite threat' performed in boxes correlated with [`]contact aggression' in the paddock (r = 0.46, p = 0.011). In conclusion, pre-exposure of young horses in neighbouring boxes may reduce [`]contact aggression', especially biting, in the paddock and [`]bite threat' shown in boxes may help to predict contact aggression when horses are later turned out together. The reduced non-aggressive interactions in the paddock in the BP test were probably a consequence of horses having exchanged these behaviours in the preceding B test. Exposing young horses in boxes next to each other may be a helpful tool before mixing them because horses meet in a safe environment that could assist in reducing the type of aggression where horses are most at risk of being injured.
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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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Heleski, C. R., McGreevy, P. D., Kaiser, L. J., Lavagnino, M., Tans, E., Bello, N., et al. (2009). Effects on behaviour and rein tension on horses ridden with or without martingales and rein inserts. The Veterinary Journal, 181(1), 56–62.
Abstract: Unsteady hand position can cause discomfort to the horse, potentially leading to conflict behaviours (CB) such as head tossing or tail lashing. Some instructors feel that martingales or elastic rein inserts can reduce discomfort caused by inexperienced and unsteady hands. Others consider these devices to be inappropriate [`]crutches'. Four horses and nine riders were tested under three conditions in random order: plain reins, adjustable training martingales (TM), and elasticised rein inserts (RI). Rein-tension data (7Â s) and behavioural data (30Â s) were collected in each direction. Rein-tension data were collected via strain-gauge transducers. Behavioural data were assessed using an ethogram of defined behaviours. No differences in the number of CB were observed. Mean rein tension for TM was higher than that of RI or controls. Relative to the withers, the head was lower for horses ridden with martingales. Carefully fitted martingales may have a place in riding schools that teach novices.
Keywords: Horse behaviour; Horse welfare; Equitation science; Rein tension; Martingales
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Henzi, S., Lusseau, D., Weingrill, T., van Schaik, C., & Barrett, L. (2009). Cyclicity in the structure of female baboon social networks. Behav. Ecol. Sociobiol., 63(7), 1015-1021.
Abstract: There is an established and very influential view that primate societies have identifiable, persistent social organizations. It assumes that association patterns reflect long-term strategic interests that are not qualitatively perturbed by short-term environmental variability. We used data from two baboon troops in markedly different habitats over three consecutive seasons to test this assumption. Our results demonstrate pronounced cyclicity in the extent to which females maintained differentiated relationships. When food was plentiful, the companionships identified by social network analysis in the food-scarce season disappeared and were replaced by casual acquaintanceships more representative of mere gregariousness. Data from the fourth, food-scarce, season at one site indicated that few companions were re-united. It is likely that this reflected stochastic variation in individual circumstances. These results suggest that attention could profitably be paid to the effects of short-term local contingencies on social dynamics, and has implications for current theories of primate cognitive evolution.
Keywords: Biomedical and Life Sciences
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Hewitt, S. E., Macdonald, D. W., & Dugdale, H. L. (2009). Context-dependent linear dominance hierarchies in social groups of European badgers, Meles meles. Anim. Behav., 77(1), 161–169.
Abstract: A social hierarchy is generally assumed to exist in those mammalian societies in which the costs and benefits of group living are distributed unevenly among group members. We analysed infrared closed-circuit television footage, collected over 3 years in Wytham Woods, Oxfordshire, to test whether social groups of European badgers have dominance hierarchies. Analysis of directed aggression between dyads revealed linear dominance hierarchies in three social-group-years, but patterns within social groups were not consistent across years. Dominance hierarchies were significantly steeper than random in five out of six social-group-years. In those social-group-years where a linear hierarchy was determined, there was an effect of sex on dominance rank, with females gaining significantly higher rank than males in two social-group-years. Overall, rank was not related to age, nor did it appear to affect the likelihood of an individual being wounded, or an individual's breeding status. The latter resulted from nonorthogonality between sex and breeding status, as there were only two breeding males. Overall, hierarchies were primarily dominated by breeding females, and may occur when breeding competition arises. Relatedness, unreciprocated allogrooming and sequential allomarking were not consistently related to levels of directed aggression across social-group-years. We suggest that dominance structures within European badger groups may be context dependent, with future study required to complete our understanding of where, and when, they arise.
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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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Hothersall, B., & Nicol, C. (2009). Role of Diet and Feeding in Normal and Stereotypic Behaviors in Horses. Clinical Nutrition, 25(1), 167–181.
Abstract: This article reviews the effects of diet on equine feeding behavior and feeding patterns, before considering the evidence that diet affects reactivity in horses. A growing body of work suggests that fat- and fiber-based diets may result in calmer patterns of behavior, and possible mechanisms that may underpin these effects are discussed. In contrast, there is little evidence that herbal- or tryptophan-containing supplements influence equine behavior in any measurable way. The role of diet in the development of abnormal oral behaviors, particularly the oral stereotypy crib-biting, is also reviewed, and suggestions for future work are presented.
Keywords: Equine behavior; Diet; Crib-biting; Stereotypy; Weaning; Tryptophan; Insulin
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Iliopoulos, Y., Sgardelis, S., Koutis, V., & Savaris, D. (2009). Wolf depredation on livestock in central Greece. Mamm. Reas., 54(1), 11–22.
Abstract: We studied wolfCanis lupus Linnaeus, 1758 -- livestock conflict in central Greece by investigating patterns of 267 verified wolf attacks on livestock for 21 months. Wolves attacked adult goats 43% and cattle 218% more than expected, whereas sheep 41% less than expected from their availability. Wolves killed less than four sheep or goats in 79%, and one cow or calf in 74% of depredation events, respectively. We recorded higher attack rates during wolf post-weaning season. Wolf attacks on strayed, or kept inside non predator-proof enclosures, sheep and goats, were on average two to four times respectively more destructive than those when livestock was guarded by a shepherd. Sheepdog use reduced losses per attack. Optimal sheepdog number ranged from 3 to 9 animals depending on flock size. Losses per attack were positively related to the number of wolves involved. Total losses per farm were positively correlated with the size of livestock unit but percentage losses per capita increased with decreasing flock size. Management implications to mitigate livestock depredation are discussed.
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Ittyerah, M., & Gaunet, F. (2009). The response of guide dogs and pet dogs ( Canis Familiaris ) to cues of human referential communication (pointing and gaze). Anim. Cogn., 12(2), 257–265.
Abstract: Abstract The study raises the question of whether guide dogs and pet dogs are expected to differ in response to cues of referential communication given by their owners; especially since guide dogs grow up among sighted humans, and while living with their blind owners, they still have interactions with several sighted people. Guide dogs and pet dogs were required to respond to point, point and gaze, gaze and control cues of referential communication given by their owners. Results indicate that the two groups of dogs do not differ from each other, revealing that the visual status of the owner is not a factor in the use of cues of referential communication. Both groups of dogs have higher frequencies of performance and faster latencies for the point and the point and gaze cues as compared to gaze cue only. However, responses to control cues are below chance performance for the guide dogs, whereas the pet dogs perform at chance. The below chance performance of the guide dogs may be explained by a tendency among them to go and stand by the owner. The study indicates that both groups of dogs respond similarly in normal daily dyadic interaction with their owners and the lower comprehension of the human gaze may be a less salient cue among dogs in comparison to the pointing gesture.
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