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Holzapfel, M., Wagner, C., & Kluth, G. et al. (2011). Zur Nahrungsökologie der Wölfe (Canis lupus) in Deutschland. Beiträge zur Jagd- und Wildforschung, 36, 117–128.
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Vallortigara, G., Chiandetti, C., & Sovrano, V. A. (2011). Brain asymmetry (animal). WIREs Cogn Sci, 2(2), 146–157.
Abstract: Once considered a uniquely human attribute, brain asymmetry has been proved to be ubiquitous among non-human animals. A synthetic review of evidence of animal lateralization in the motor, sensory, cognitive, and affective domains is provided, together with a discussion of its development and possible biological functions. It is argued that investigation of brain asymmetry in a comparative perspective may favor the link between classical neuropsychological studies and modern developmental and evolutionary biology approaches. WIREs Cogni Sci 2011 2 146–157 DOI: 10.1002/wcs.100 For further resources related to this article, please visit the WIREs website
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Bartoš, L., Bartošová, J., Pluhácek, J., & Šindelárová, J. (2011). Promiscuous behaviour disrupts pregnancy block in domestic horse mares. Behavioral Ecology and Sociobiology, 65(8), 1567–1572.
Abstract: Based on questionnaires from horse breeders, we found that bringing a pregnant mare which had been mated away from home into a vicinity of a familiar male who was not the father of her foetus increased probability of pregnancy disruption. These mares aborted in 31% of cases, while none of those mated within the home stable aborted. Repeated sexual activity either by a stallion or dominant gelding from the normal home group was observed shortly after the mare came from away-mating. Pregnant mares isolated from home males by a fence were even seen soliciting them over the fence. We speculate that, once returned to the home “herd”, and introduced to familiar males, mares were more likely to terminate their pregnancy to save energy and avoid likely future infanticidal loss of their progeny by dominant male(s) of the home social group. This is a newly discovered phenomenon where a mare manipulates the male’s paternity assessment by promiscuous mating. It may explain a common increased incidence of foetal loss in domestic horses occurring in nearly 40% of pregnancies. We conclude that the common practice of transporting the mare for mating and then bringing her back to an environment with males, stallions or geldings, which did not sire the foetus, is the main cause of high percentages of pregnancy disruption in domestic horses.
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Sheriff, M. J., Dantzer, B., Delehanty, B., Palme, R., & Boonstra, R. (2011). Measuring stress in wildlife: techniques for quantifying glucocorticoids. Oecologia, 166(4), 869–887.
Abstract: Stress responses play a key role in allowing animals to cope with change and challenge in the face of both environmental certainty and uncertainty. Measurement of glucocorticoid levels, key elements in the neuroendocrine stress axis, can give insight into an animal’s well-being and can aid understanding ecological and evolutionary processes as well as conservation and management issues. We give an overview of the four main biological samples that have been utilized [blood, saliva, excreta (feces and urine), and integumentary structures (hair and feathers)], their advantages and disadvantages for use with wildlife, and some of the background and pitfalls that users must consider in interpreting their results. The matrix of choice will depend on the nature of the study and of the species, on whether one is examining the impact of acute versus chronic stressors, and on the degree of invasiveness that is possible or desirable. In some cases, more than one matrix can be measured to achieve the same ends. All require a significant degree of expertise, sometimes in obtaining the sample and always in extracting and analyzing the glucocorticoid or its metabolites. Glucocorticoid measurement is proving to be a powerful integrator of environmental stressors and of an animal’s condition.
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Baragli, P., Vitale, V., Paoletti, E., Sighieri, C., & Reddon, A. R. (2011). Detour behaviour in horses (Equus caballus). J. Ethol., 29(2), 227–234.
Abstract: The objective of this study was to investigate the ability of horses (Equus caballus) to detour around symmetric and asymmetric obstacles. Ten female Italian saddle horses were each used in three detour tasks. In the first task, the ability to detour around a symmetrical obstacle was evaluated; in the second and third tasks subjects were required to perform a detour around an asymmetrical obstacle with two different degrees of asymmetry. The direction chosen to move around the obstacle and time required to make the detour were recorded. The results suggest that horses have the spatial abilities required to perform detour tasks with both symmetric and asymmetric obstacles. The strategy used to perform the task varied between subjects. For five horses, lateralized behaviour was observed when detouring the obstacle; this was consistently in one direction (three on the left and two on the right). For these horses, no evidence of spatial learning or reasoning was found. The other five horses did not solve this task in a lateralized manner, and a trend towards decreasing lateralization was observed as asymmetry, and hence task difficulty, increased. These non-lateralized horses may have higher spatial reasoning abilities.
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Jørgensen, G. H. M., Liestøl, S. H. - O., & Bøe, K. E. (2011). Effects of enrichment items on activity and social interactions in domestic horses (Equus caballus). Appl. Anim. Behav. Sci., 129(2-4), 100–110.
Abstract: The aim of this study was to investigate the use of items intended to provide enrichment during turnout, both for individual and group kept horses in an attempt to reduce the amount of passive behaviours. The study was divided into two parts, where study 1 involved eight horses rotated through eight individual paddocks, each containing one of seven enrichment items and one paddock being kept without item, functioning as a control. The horses' item-directed behaviours; passive behaviours or other non-item related activities were scored using instantaneous sampling, every minute for 1 h at the beginning and the end of the turnout period. Study 2 involved six horse groups (3-6 horses) and the same scoring methods and ethogram as in study 1. The four items that the horses interacted the most with during study 1 (straw STRA, ball filled with concentrates CBALL, branches BRAN and scratching pole POLE) are investigated in study 2. In addition, the amount of social interactions was recorded. Both horses kept individually (P < 0.05) and in groups (P < 0.0001) performed significantly more item-directed behaviours towards edible items like STRA and CBALL than other objects. There was, however, no overall relation between the numbers of item-directed behaviours and the number of passive behaviours observed, indicating that the enrichment items did not alone reduce the amount of passive behaviours during turnout periods. Such a reduction was, however, only apparent when horses spent more time eating green leaves growing on the paddock surface (R = -0.97 study 1, R = -0.67 study 2, P < 0.0001). Access to STRA in group kept horses also seemed to reduce the amount of agonistic behaviours (P < 0.0001). In conclusion, if grass is not available in paddocks, the provision of roughage reduces the amount of passive behaviours in singly kept horses and it also reduces the risk of agonistic interactions between horses kept in group.
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Weissing, F. J. (2011). Animal behaviour: Born leaders. Nature, 474(7351), 288–289.
Abstract: Social animals face a dilemma. To reap the benefits of group living, they have to stay together. However, individuals differ in their preferences as to where to go and what to do next. If all individuals follow their own preferences, group coherence is undermined, resulting in an outcome that is unfavourable for everyone. Neglecting one's own preferences and following a leader is one way to resolve this coordination problem. But what attributes make an individual a 'leader'? A modelling study by Johnstone and Manica1 illuminates this question.
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Stuber, G. D., Sparta, D. R., Stamatakis, A. M., van Leeuwen, W. A., Hardjoprajitno, J. E., Cho, S., et al. (2011). Excitatory transmission from the amygdala to nucleus accumbens facilitates reward seeking. Nature, advance online publication.
Abstract: The basolateral amygdala (BLA) has a crucial role in emotional learning irrespective of valence1, 2, 3, 4, 5, 21, 22, 23. The BLA projection to the nucleus accumbens (NAc) is thought to modulate cue-triggered motivated behaviours4, 6, 7, 24, 25, but our understanding of the interaction between these two brain regions has been limited by the inability to manipulate neural-circuit elements of this pathway selectively during behaviour. To circumvent this limitation, we used in vivo optogenetic stimulation or inhibition of glutamatergic fibres from the BLA to the NAc, coupled with intracranial pharmacology and ex vivo electrophysiology. Here we show that optical stimulation of the pathway from the BLA to the NAc in mice reinforces behavioural responding to earn additional optical stimulation of these synaptic inputs. Optical stimulation of these glutamatergic fibres required intra-NAc dopamine D1-type receptor signalling, but not D2-type receptor signalling. Brief optical inhibition of fibres from the BLA to the NAc reduced cue-evoked intake of sucrose, demonstrating an important role of this specific pathway in controlling naturally occurring reward-related behaviour. Moreover, although optical stimulation of glutamatergic fibres from the medial prefrontal cortex to the NAc also elicited reliable excitatory synaptic responses, optical self-stimulation behaviour was not observed by activation of this pathway. These data indicate that whereas the BLA is important for processing both positive and negative affect, the glutamatergic pathway from the BLA to the NAc, in conjunction with dopamine signalling in the NAc, promotes motivated behavioural responding. Thus, optogenetic manipulation of anatomically distinct synaptic inputs to the NAc reveals functionally distinct properties of these inputs in controlling reward-seeking behaviours.
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Ramsden, S., Richardson, F. M., Josse, G., Thomas, M. S. C., Ellis, C., Shakeshaft, C., et al. (2011). Verbal and non-verbal intelligence changes in the teenage brain. Nature, advance online publication.
Abstract: Intelligence quotient (IQ) is a standardized measure of human intellectual capacity that takes into account a wide range of cognitive skills1. IQ is generally considered to be stable across the lifespan, with scores at one time point used to predict educational achievement and employment prospects in later years1. Neuroimaging allows us to test whether unexpected longitudinal fluctuations in measured IQ are related to brain development. Here we show that verbal and non-verbal IQ can rise or fall in the teenage years, with these changes in performance validated by their close correlation with changes in local brain structure. A combination of structural and functional imaging showed that verbal IQ changed with grey matter in a region that was activated by speech, whereas non-verbal IQ changed with grey matter in a region that was activated by finger movements. By using longitudinal assessments of the same individuals, we obviated the many sources of variation in brain structure that confound cross-sectional studies. This allowed us to dissociate neural markers for the two types of IQ and to show that general verbal and non-verbal abilities are closely linked to the sensorimotor skills involved in learning. More generally, our results emphasize the possibility that an individual’s intellectual capacity relative to their peers can decrease or increase in the teenage years. This would be encouraging to those whose intellectual potential may improve, and would be a warning that early achievers may not maintain their potential.
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Burgon, H. L. (2011). ‘Queen of the world’: experiences of ‘at-risk’ young people participating in equine-assisted learning/therapy. Journal of Social Work Practice, 25(02), 165–183.
Abstract: There is a significant body of research into the benefits of animal-assisted therapy (AAT) but less into the fields known as equine-assisted learning and therapy (EAL/EAT) where horses are incorporated in therapeutic and learning interventions. This paper explores the experiences of seven ?at-risk? young people who participated in a therapeutic horsemanship (TH) programme. The study followed a practice-near approach seeking to capture the young people's experiences within a participative ethnography. Themes related to the risk and resilience literature such as self-confidence, self-esteem, self-efficacy and a sense of mastery, empathy and the opening of positive opportunities are explored in this paper.
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