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Schmidt, A., Aurich, J., Möstl, E., Müller, J., & Aurich, C. (2010). Changes in cortisol release and heart rate and heart rate variability during the initial training of 3-year-old sport horses. Horm Behav, 58(4), 628–636.
Abstract: Based on cortisol release, a variety of situations to which domestic horses are exposed have been classified as stressors but studies on the stress during equestrian training are limited. In the present study, Warmblood stallions (n = 9) and mares (n = 7) were followed through a 9 respective 12-week initial training program in order to determine potentially stressful training steps. Salivary cortisol concentrations, beat-to-beat (RR) interval and heart rate variability (HRV) were determined. The HRV variables standard deviation of the RR interval (SDRR), RMSSD (root mean square of successive RR differences) and the geometric means standard deviation 1 (SD1) and 2 (SD2) were calculated. Nearly each training unit was associated with an increase in salivary cortisol concentrations (p < 0.01). Cortisol release varied between training units and occasionally was more pronounced in mares than in stallions (p < 0.05). The RR interval decreased slightly in response to lunging before mounting of the rider. A pronounced decrease occurred when the rider was mounting, but before the horse showed physical activity (p < 0.001). The HRV variables SDRR, RMSSD and SD1 decreased in response to training and lowest values were reached during mounting of a rider (p < 0.001). Thereafter RR interval and HRV variables increased again. In contrast, SD2 increased with the beginning of lunging (p < 0.05) and no changes in response to mounting were detectable. In conclusion, initial training is a stressor for horses. The most pronounced reaction occurred in response to mounting by a rider, a situation resembling a potentially lethal threat under natural conditions.
Keywords: Horse; Initial training; Cortisol; Heart rate variability
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Shultz, S., & Finlayson, L. V. (2010). Large body and small brain and group sizes are associated with predator preferences for mammalian prey. Behav. Ecol., 21(5), 1073–1079.
Abstract: Predation is a major force in shaping biological communities, both over ecological and evolutionary timescales. In response to predation pressure, prey have evolved characteristics designed to mitigate predation pressure. We evaluated predator foraging biases in relation to prey characteristics across 16 vertebrate communities. We show that although predator biases vary, some prey traits are consistently associated with predator diet composition. Within their acceptable prey size range, predators show positive bias toward larger bodied prey, small-brained prey (controlling for body size), small group size, and terrestriality. Thus, whether predator foraging decisions are passive or active, predator choice exerts differential pressure on prey species according to prey characteristics. Predator biases also were positively associated with early age at maturity, supporting the role of mortality in driving life-history characteristics. These results support several theoretical models of predation including its role as a selective force driving evolutionary changes in life history, brain size and sociality, optimal diet theory, and antiapostatic predation.
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Sárová, R., Spinka, M., Panamá, J. L. A., & Simecek, P. (2010). Graded leadership by dominant animals in a herd of female beef cattle on pasture. Anim. Behav., 79(5), 1037–1045.
Abstract: The role of dominant individuals in leading groups of animals is not yet well understood. We investigated whether dominant beef cows, Bos taurus, have more influence on herd movement on pasture than more subordinate cows. A herd of 15 Gasconne cows was observed for a 3-week period between dawn and dusk. The positions of all adult cows were recorded with GPS collars at 1 min intervals and the behaviour of each cow was recorded in 5 min scans. The dominance hierarchy was recorded by ad libitum sampling. Through cluster analysis of the recorded data, we distinguished three herd behaviour patterns: resting, foraging and travelling. Dominant cows were closer to the front of the herd during both travelling and foraging. During travelling, more dominant cows also had more direct trajectories and were more aligned both with their nearest neighbours and with the whole herd. During foraging, the trajectories of dominant cows were shorter than those of subordinate cows. The results indicate that foraging and short-distance travelling movements by female beef cattle are not led by any particular individual but rather are influenced by a graded type of leadership; that is, the more dominant a cow is, the stronger the influence it may have on the movements of the herd.
Keywords: Bos taurus; cattle; dominance; foraging; Gps; group movement; leadership
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Benhajali, H., Richard-Yris, M. - A., Ezzaouia, M., Charfi, F., & Hausberger, M. (2010). Reproductive status and stereotypies in breeding mares: A brief report. Appl. Anim. Behav. Sci., 128(1-4), 64–68.
Abstract: The aim of this study was to investigate the relationship between age, reproductive status and sire of the mare and the tendency to perform stereotypies. One hundred and fourteen purebred Arab mares, offspring of 39 sires ( offspring per sire) and aged 4-21 years () were observed from the 30th March to the 15th of May 2005 using instantaneous scan sampling. We used a multivariate logistic regression in order to study the relationship between age, reproductive status and sire of the mare and the tendency to perform stereotypies. 28% of the observed mares showed stereotypic behaviour, mostly weaving (22%). Neither age (χ2 Wald = 9.36, p = 0.89) nor sire (χ2 Wald = 4.34, p = 1.0) affected the occurrence of stereotypies whilst the reproductive status of the mare influenced significantly the occurrence (χ2 Wald = 10.75, p = 0.001) but also the type (χ2 = 12.1, p < 0.001) of stereotypic behaviour. Weaving was more frequent in non foaling mares (41.4%) than in foaling mares (1.8%) that performed mostly stall-walking.
Keywords: Stereotypies; Breeding mare; Sire; Reproductive-status
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Pluhácek, J., Bartos, L., Bartosová, J., & Kotrba, R. (2010). Feeding behaviour affects nursing behaviour in captive plains zebra (Equus burchellii). Appl. Anim. Behav. Sci., 128(1-4), 97–102.
Abstract: Equids spend more than half of the day feeding. Lactation is a very demanding form of maternal investment. In an environment such as a zoo, where no grass but several feeding sites are present, conflict between suckling behaviour of the foal and feeding behaviour of the lactating mother should occur. We observed 20 foals of captive plains zebra, Equus burchellii, at the Dvur Králové Zoo, Czech Republic, and collected data concerning suckling events during 17 months of observation. First, we examined whether feeding by the mother while nursing affected suckling behaviour. We found that when the mother was feeding, the proportion of suckling bouts she terminated decreased with increasing age of the foal, whereas it did not change when she was not feeding. This result supported the trade-off between suckling and feeding behaviour which has been reported in other ungulates. Second, we examined what affected interruptions of feeding behaviour of the mother during the suckling bout. The proportion of interruptions of feeding by the mother during nursing increased with increasing age of her foal. This coincides with declining time spent nursing. In addition, younger mothers interrupted their feeding behaviour during suckling bouts more often than older ones. Mothers interrupted feeding during the suckling bout more often when they nursed a daughter than when they nursed a son. The results of our study show that feeding while suckling could reduce parent-offspring conflict and improve welfare of captive foals and mares.
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Smith, J. E., Van Horn, R. C., Powning, K. S., Cole, A. R., Graham, K. E., Memenis, S. K., et al. (2010). Evolutionary forces favoring intragroup coalitions among spotted hyenas and other animals. Behav. Ecol., 21(2), 284–303.
Abstract: Coalitionary support in agonistic interactions represents cooperation because intervening in a fight is potentially costly to the donor of support but benefits the recipient. Here, we first review the characteristics of, and evolutionary forces favoring, intragroup coalitions in 49 species and find that patterns of intragroup coalition formation are remarkably similar between primates and nonprimates. We then test hypotheses suggesting kin selection, reciprocal altruism, and direct benefits as adaptive explanations for coalitionary interventions among adult female spotted hyenas (Crocuta crocuta) belonging to a large social group in Kenya. As predicted by kin selection theory, females supported close kin most often, and the density (connectedness) of cooperation networks increased with genetic relatedness. Nevertheless, kinship failed to protect females from coalitionary attacks. We found no evidence of enduring alliances based on reciprocal support among unrelated adult females. Instead, donors generally minimized costs to themselves, intervening most often during low-intensity fights and when feeding opportunities were unavailable. Females also gained direct benefits from directing coalitionary attacks toward subordinates. Finally, females monitored the number of dominant bystanders in the “audience” at fights and modified their level of cooperation based on this knowledge. Overall, hyenas made flexible decisions regarding whether or not to intervene in fights, modifying their tendency to cooperate based on multiple types of information about their immediate social and ecological environments. Taken together, these findings indicate that the combined evolutionary forces of kin selection and direct benefits derived from reinforcing the status quo drive coalitionary interventions among adult female spotted hyenas.
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Rogers, L. J. (2010). Relevance of brain and behavioural lateralization to animal welfare. Appl. Anim. Behav. Sci., 127(1-2), 1–11.
Abstract: The left and right sides of the brain are specialised to process information in different ways and to control different categories of behaviour. Research on a range of species has shown that the left hemisphere controls well-established patterns of behaviour performed in non-stressful situations, whereas the right hemisphere responds to unexpected stimuli and controls escape and other emergency responses. The known functions of each hemisphere are summarised in this paper. Then it is hypothesised that stressed animals rely on predominant use of the right hemisphere, and that a bias to use the right or left hemisphere, respectively, may explain the behavioural differences between animals with a negative cognitive bias and those with a positive cognitive bias. In some species of primates it has been shown that the preferred limb used to pick up food when the animal is in a relaxed state reflects the dominant hemisphere and may be an accessible measure indicating susceptibility to stress and tendency towards positive versus negative cognitive bias. Hence, limb preference might be a useful measure of such tendencies in domesticated species. Some difficulties in determining a relevant measure of limb preference in non-primate species are mentioned, followed by the suggestion that eye preferences for viewing certain stimuli may be a useful measure in species with laterally placed eyes. Finally, effects of experience on the development of hemispheric dominance are discussed, leading to a suggestion that the welfare of domestic animals may be enhanced by ensuring development of left hemisphere dominance (e.g. by exposing chick embryos to light) and by shifting right to left hemisphere dominance in animals with negative cognitive bias.
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Hartmann, E. (2010). Managing horses in groups to improve horse welfare and human safety. Ph.D. thesis, , .
Abstract: Managing horses in groups to improve horse welfare and human safety
: reactions to mixing and separation Hartmann, Elke (2010) Managing horses in groups to improve horse welfare and human safety . Doctoral diss. Dept. of Animal Environment and Health, SLU. Acta Universitatis agriculturae Sueciae vol. 2010:87. Full text available as: 439 Kb Abstract The aim of this thesis was to investigate whether specific anecdotal concerns related to keeping horses in groups are supported by science and, if so, provide scientifically based recommendations that could be implemented in practice. The aim of studies I and II was to identify methods for mixing unfamiliar horses that could minimise aggressive interactions and associated risk of injury. Results of study I revealed that pre-exposure of young horses in neighbouring boxes tended to lower contact-aggression (e.g. kicks, strikes) and biting behaviour in particular was reduced when the same pair of horses subsequently met in a paddock. This was not found when older horses were mixed (study II). Aggressive behaviour received by a new horse was not significantly different in meetings when it met one other horse compared to meeting two unfamiliar horses at the same time. Removing a horse from a group of four in study III was generally unproblematic. Most horses approached the handler when she was catching the horse and while standing with it in the middle of the paddock. Thus, potential risk may be higher in situations when the handler remains relatively stationary, as other horses of the group have time to approach. Rank did not influence the number of horses following to the paddock gate and interactions between horses were rare. Since horses naïve to social separation may be more difficult to handle away from the group, the objective in study IV was to investigate whether the initial presence of a companion horse would modify responses to separation. Results revealed no significant differences in heart rates and the number of training sessions required when the horses were subsequently trained in the absence of the partner compared to horses trained alone from the start. In summary, results give little support for the original areas of concerns about mixing and separating horses. Risk of injury to both horses and humans should not be overestimated when handling horses in groups, but being aware of potential risk situations and being able to react accordingly is likely to increase horse welfare and human safety. Faculty: Faculty of Veterinary Medicine and Animal Science Keywords: equine, behaviour, welfare, housing, mixing, aggression, injury, separation, habituation, learning Agrovoc terms: horses, behaviour, bites, injurious factors, animal learning, animal welfare, sweden ISBN: 978-91-576-7532-3 Series.: Acta Universitatis agriculturae Sueciae ISSN: 1652-6880 Volume: 2010:87 Papers/manuscripts: I. Hartmann, E., Winther Christensen, J., Keeling, L.J. (2009). Social interactions of unfamiliar horses during paired encounters: Effect of pre-exposure on aggression level and so risk of injury. Applied Animal Behaviour Science 121, 214-221. II. Hartmann, E., Rundgren, M., Keeling, L.J. (in press). Comparison of 3 methods for mixing unfamiliar horses (Equus caballus). Journal of Equine Veterinary Behavior: Clinical Applications and Research. III. Hartmann, E., Søndergaard, E., Keeling, L.J. Identifying potential risk situations for humans when removing horses from groups. Manuscript. IV. Hartmann, E., Christensen, J.W., Keeling, L.J. (in press). Training young horses to social separation: Effect of a companion horse on training efficiency. Equine Veterinary Journal. Number of pages: 75 Year of publication: 2010 Language: eng ID Code: 2396 Deposited By: Hartmann, Elke Deposited On: 08 November 2010 |
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Seed, A., & Byrne, R. (2010). Animal Tool-Use. Curr Biol, 20(23), R1032–R1039.
Abstract: The sight of an animal making and using a tool captivates scientists and laymen alike, perhaps because it forces us to question some of our ideas about human uniqueness. Does the animal know how the tool works? Did it anticipate the need for the tool and make it in advance? To some, this fascination with tools seems arbitrary and anthropocentric; after all, animals engage in many other complex activities, like nest building, and we know that complex behaviour need not be cognitively demanding. But tool-using behaviour can also provide a powerful window into the minds of living animals, and help us to learn what capacities we share with them -- and what might have changed to allow for the incontrovertibly unique levels of technology shown by modern humans.
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Zenzinger, S. (2010). Experimentelle Untersuchungen zur optischen Kommunikation bei im Zoo gehaltenen Schabracken- und Flachlandtapiren (Tapirus indicus und Tapirus terrestris). Der Zoologische Garten, 79(4-5), 162–174.
Abstract: Until now, unlike their relatives, rhinos and horses tapirs have received considerably less attention in studies about communication. Therefore, it was the aim of this study to test which stimuli contain optical information for tapirs. For this purpose, the reactions of tapirs on optical stimuli (posters with edited tapir silhouettes) were examined. Research visits took place at the zoos of Berlin, Dortmund, Heidelberg, Munich, Nuremberg and Osnabrück during the year 2006. A total of 23 individuals, thereof 8 (5.3) Malayan tapirs (Tapirus indicus) and 15 (5.10) Lowland tapirs (Tapirus terrestris) attended the experiment. The results of the optical test with variously intense edited tapir silhouettes speak for the importance of the white ear rims as a family specific key stimulus. But that effect could not be amplified by adding a greater extent of white to the silhouette. Tapirs of both species reacted most strongly to the normal tapir silhouette followed by a silhouette without proboscis.
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