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Mizuguchi, M., Arai, M., Ke, Y., Nitta, K., & Kuwajima, K. (1998). Equilibrium and kinetics of the folding of equine lysozyme studied by circular dichroism spectroscopy. Journal of Molecular Biology, 283(1), 265–277.
Abstract: The equilibrium unfolding and the kinetics of unfolding and refolding of equine lysozyme, a Ca2+-binding protein, were studied by means of circular dichroism spectra in the far and near-ultraviolet regions. The transition curves of the guanidine hydrochloride-induced unfolding measured at 230 nm and 292.5 nm, and for the apo and holo forms of the protein have shown that the unfolding is well represented by a three-state mechanism in which the molten globule state is populated as a stable intermediate. The molten globule state of this protein is more stable and more native-like than that of α-lactalbumin, a homologous protein of equine lysozyme. The kinetic unfolding and refolding of the protein were induced by concentration jumps of the denaturant and measured by stopped-flow circular dichroism. The observed unfolding and refolding curves both agreed well with a single-exponential function. However, in the kinetic refolding reactions below 3 M guanidine hydrochloride, a burst-phase change in the circular dichroism was present, and the burst-phase intermediate in the kinetic refolding is shown to be identical with the molten globule state observed in the equilibrium unfolding. Under a strongly native condition, virtually all the molecules of equine lysozyme transform the structure from the unfolded state into the molten globule, and the subsequent refolding takes place from the molten globule state. The transition state of folding, which may exist between the molten globule and the native states, was characterized by investigating the guanidine hydrochloride concentration-dependence of the rate constants of refolding and unfolding. More than 80% of the hydrophobic surface of the protein is buried in the transition state, so that it is much closer to the native state than to the molten globule in which only 36% of the surface is buried in the interior of the molecule. It is concluded that all the present results are best explained by a sequential model of protein folding, in which the molten globule state is an obligatory folding intermediate on the pathway of folding.
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Merkies, K., McKechnie, M. J., & Zakrajsek, E. (2018). Behavioural and physiological responses of therapy horses to mentally traumatized humans. Applied Animal Behaviour Science, .
Abstract: The benefits to humans of equine-assisted therapy (EAT) have been well-researched, however few studies have analyzed the effects on the horse. Understanding how differing mental states of humans affect the behaviour and response of the horse can assist in providing optimal outcomes for both horse and human. Four humans clinically diagnosed and under care of a psychotherapist for Post-Traumatic Stress Disorder (PTSD) were matched physically to four neurotypical control humans and individually subjected to each of 17 therapy horses loose in a round pen. A professional acting coach instructed the control humans in replicating the physical movements of their paired PTSD individual. Both horses and humans were equipped with a heart rate (HR) monitor recording HR every 5secs. Saliva samples were collected from each horse 30 min before and 30 min after each trial to analyze cortisol concentrations. Each trial consisted of 5 min of baseline observation of the horse alone in the round pen after which the human entered the round pen for 2 min, followed by an additional 5 min of the horse alone. Behavioural observations indicative of stress in the horse (gait, head height, ear orientation, body orientation, distance from the human, latency of approach to the human, vocalizations, and chewing) were retrospectively collected from video recordings of each trial and analyzed using a repeated measures GLIMMIX with Tukey's multiple comparisons for differences between treatments and time periods. Horses moved slower (p < 0.0001), carried their head lower (p < 0.0001), vocalized less (p < 0.0001), and chewed less (p < 0.0001) when any human was present with them in the round pen. Horse HR increased in the presence of the PTSD humans, even after the PTSD human left the pen (p < 0.0001). Since two of the PTSD/control human pairs were experienced with horses and two were not, a post-hoc analysis showed that horses approached quicker (p < 0.016) and stood closer (p < 0.0082) to humans who were experienced with horses. Horse HR was lower when with inexperienced humans (p < 0.0001) whereas inexperienced human HR was higher (p < 0.0001). Horse salivary cortisol did not differ between exposure to PTSD and control humans (p > 0.32). Overall, behavioural and physiological responses of horses to humans are more pronounced based on human experience with horses than whether the human is diagnosed with a mental disorder. This may be a reflection of a directness of movement associated with humans who are experienced with horses that makes the horse more attentive. It appears that horses respond more to physical cues from the human rather than emotional cues. This knowledge is important in tailoring therapy programs and justifying horse responses when interacting with a patient in a therapy setting.
Keywords: Equine-assisted therapy; Ptsd; Horse; Behaviour; Cortisol; Heart rate
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McDonnell, S. M. (2008). Human-horse interactions: Where are the behaviorists in 2008? In IESM 2008.
Abstract: This presentation will include commentary on work presented at this meeting as representative of the rapidly growing body of equine behavior science evidence relevant to human-horse interaction and the welfare of domestic, feral, and wild horses.
A substantial literature has accumulated detailing the behavior patterns of wild and feral equid populations, and to some extent the behavior of horses in various domestic environments. Professor Klingel“s and Professor Houpt”s work, begun nearly 40 years ago, continues to inspire colleagues around the world to qualitatively and quantitatively describe behavior of equids in a variety of environments. Several examples of the importance of this type of work to human-horse interaction and horse welfare are evident in throughout the meeting. It forms the basis for assessing the disturbance of behavior in wildlife management projects such as fertility manipulations (Hopkins; Ransom & Cade) or species reintroduction (Kaczensky et al). Study of the apparent variability in observations among the populations will lead to a better understanding of environmental and other factors, which will have fruitful application to welfare of horses both in domestic and natural environments. Unfortunately, this work always brings to mind what I perceive as a nagging threat to horse welfare and quality of human-horse interaction is misinformation concerning natural horse behavior. Natural horse behavior seems to be of great general interest, but unfortunately inaccuracies and misinterpretations are pervasive in popular “horse culture” and continue to be a conspicuous influence on management and training of domestic horses. Unfortunately, this misinformation often makes its way and influences equine education, both lay and equine science/veterinary education. Comparative observational study of behavior of horses in all settings by trained behaviorists, along with research designed to address purported implications for management of domestic horses, along with initiatives to transfer knowledge to educators at all levels should be encouraged. Included in this meeting is considerable work addressing questions of domestic management practices such as forced weaning, transportation, stabling, and arbitrary grouping and regrouping of horses. This adds to a growing body of applied physiology and behavior research that has established trained behaviorists as a critical resource on teams making decisions on humane management. Also well represented in work presented at this meeting is the exploration of cognition, perception, and temperament in horses. It is personally pleasing to see examples of direct investigation of the ability of the horse to respond to subtle human posture and gesture, which for many of us has represented just annoying possible confounders of earlier cognition studies. Behaviorists trained in perception and learning will no doubt contribute enormously to this exciting area of investigation. |
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von Borstel, U. (2008). An overview of educational offerings in equine science and -management in Canada. In IESM 2008.
Abstract: Canada has a variety of educational offerings in equine management at the diploma and certificate level offered by universities and colleges, as well as by industry supported centres. However, it was not until 2007 that the first degree-based program in equine science was launched. Offered by the University of Guelph, the Bachelor of Bio- Resource Management – Equine Management program is designed for students who do not intend to pursue post-graduate studies and are strongly focused on securing employment that makes use of the knowledge acquired in their bachelor's degree. The courses in the BSc-program include basic natural sciences as well as equine-specific courses with a focus on management of equine related businesses and events. Diploma and certificate programs usually include only specifically equine-related courses e.g. in anatomy and physiology, health, business, facility management and nutrition. All diploma and certificate programs, and to a slightly lesser extent the BSc program, have a strong focus on applied learning with the intent to provide highly trained workers for the industry. Unique in Canada are the entirely online-taught Diploma in Equine Studies, the Certificate in Equine Business Management and the Equine Science Certificate offered by Equine Guelph and the University of Guelph"s continuing education. Students of these programs have access to a virtual classroom via the internet, and therefore access to instructors and guest speakers from the industry throughout the course. The Canadian certificate programs typically take one year (two semesters), the diploma programs two years (four semesters), while the BSc program takes four years (eight semesters). The BSc program requires approximately 2000 hours of in-class time plus roughly twice the amount spent on assignments and studying, totalling to an overall workload of roughly 6000 hours. Most programs require the completion of Grade 12 or equivalent for admission, and in all programs a background and experience with horses is not required for admission, however it is usually deemed beneficial. Career options for BSc-graduates include barn management, riding instructor or coach, professional rider, judge, steward, course designer, equine-assisted therapy, veterinary assistant, event manager, nutrition consultant, retail sales in tack and equipment, equine sales and marketing, agriculture extension services, college lecturer, consultant and technical advisor, and media relations. Career options for the diploma and certificate program graduates generally include similar areas, with a focus on hands-on work and direct interaction with horses such as employment as grooms, trainers and barn managers.
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Nagy, K., Bodó, G., Bárdos, G., & Harnos, A. (2008). Is modified Forssell"s operation superior to cribbing collar in preventing crib-biting in horses? In IESM 2008.
Abstract: Crib-biting (wind-sucking) might be a coping response of the horses to the challenges of
uncontrolled environmental events. Prevention of this stereotypic behaviour evokes physiological responses consistent with increased stress. Reducing the incidence of cribbiting, however, is important in order to prevent undesirable physical and behavioural consequences (tooth erosion, altered gut function, gastric inflammation/ulceration, colic, etc.). Common treatment of crib-biting is the application of a cribbing collar, which limits the flexion of the neck making this stereotypic movement uncomfortable and difficult. Another method, the modified Forssell"s operation, is becoming more and more popular amongst the horse owners. It is based on the removal of the muscles used in crib-biting (m.omohyoideus, m.sternohyoideus, m.sternothyrohyoideus) and the ventral branches of the spinal accessory nerves. Surveys on the success of this surgical procedure have revealed inconsistent results, and, contrary to the cribbing collar, its effect on the stress level have not been studied either. The aim of our study was to determine whether the modified Forssell"s procedure is superior to the cribbing collar treatment. Differences in stress management was tested by a crib-biting provoking test, in which surgically treated horses, crib-biting horses, crib-biting horses with cribbing collar, and normal horses (those showing no stereotypies), altogether 56 horses were compared. In this test, a food bucket had been placed out of the reach of the animal, from which titbits were given 3 times. Behaviour and heart rate variability (HRV) of the horses were recorded and analysed throughout the test. Hypotheses were tested by linear mixed model. According to our results, both prevention methods (collar or surgery) inhibited crib-biting successfully though not totally. Regarding behaviour and heart rate variability, horses prevented from crib-biting (by collar or surgery) differed significantly from crib-biting and normal horses but not from each other. Normal horses were usually trying to reach the food-bucket while present and were standing still afterwards, whereas the other three groups had not really made efforts to reach the bucket, spent less time with resting, and performed or tried crib-biting. During the stress-test, normal and crib-biting horses had shown good stress-adaptation to the challenge since their HRV, after an initial increase, returned to the basal value by the end. On the contrary, HRV of the two prevented groups remained elevated and showed large oscillations throughout. They had not found a successful coping behaviour either. Our results suggest that since prevention may significantly increase distress, the treatment in itself, without changing the motivation of the horse to perform the replacement behaviour – it seems to be unsatisfactory and insufficient. After prevention the motivation of the horse to perform crib-biting should be addressed. In addition, considering that prevention by collar and surgery had not resulted in any significant behavioural or physiological differences, the superiority of the modified Forssell"s procedure might be questioned. However, the surgery might be recommended if treatment with collar is ineffective. |
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Krueger, K. (Ed.). (2008). Proceedings of the International Equine Science Meeting 2008. Wald: Xenophon Verlag.
Abstract: Target group: Biologists, Psychologists, Veterinarians and Professionals
Meeting target: Because the last international meeting on Equine Science took place a couple years ago, there is an urgent need for equine scientists to exchange scientific knowledge, coordinate research provide knowledge for practical application, and discus research results among themselves and with professionals who work with horses. Additionally, dialog concerning the coordination of the study “Equitation Science” in Europe is urgently needed. Coordination and cooperation shall arise from the meeting, enrich the research, and advance the application of scientific knowledge for the horses` welfare. |
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McGreevy, P. D., & McLean, A. N. (2007). Roles of learning theory and ethology in equitation. Journal of Veterinary Behavior: Clinical Applications and Research, 2(4), 108–118.
Abstract: By definition, ethology is primarily the scientific study of animal behavior, especially as it occurs in a natural environment; applied ethology being the study of animal behavior in the human domain. The terms equine ethology and ethological training are becoming commonplace in the equestrian domain, yet they seem to be used with a conspicuous lack of clarity and with no mention of learning theory. Most of what we do to train horses runs counter to their innate preferences. This article summarizes the ethological challenges encountered by working horses and considers the merits and limitations of ethological solutions. It also questions the use of terms such as “alpha” and “leader” and examines aspects of learning theory, equine cognition, and ethology as applied to horse training and clinical behavior modification. We propose 7 training principles that optimally account for the horse's ethological and learning abilities and maintain maximal responsivity in the trained horse. These principles can be summarized as: (1) use learning theory appropriately; (2) train easy-to-discriminate signals; (3) train and subsequently elicit responses singularly; (4) train only one response per signal; (5) train all responses to be initiated and subsequently completed within a consistent structure; (6) train persistence of current operantly conditioned responses; and (7) avoid and disassociate flight responses. Adherence to these principles and incorporating them into all horse training methodologies should accelerate training success, reduce behavioral wastage of horses, and improve safety for both humans and horses.
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Grogan, E. H., & McDonnell, S. M. (2005). Mare and Foal Bonding and Problems. Clinical Techniques in Equine Practice, 4(3), 228–237.
Abstract: A number of specific behavioral responses have been identified in mares and foals as the presumed behavioral interactive sequences supporting bonding. With the exception of the severely physically compromised foal, most failures of the mare foal bond appear to result from inadequate behavior of the mare. Six distinct forms of maternal behavior problems include ambivalence of the mare toward her foal, fear of the foal, nursing only avoidance of the foal, extreme protectiveness of the foal that becomes problematic in domestic confinement, savage attack (true rejection), and stealing or adoption of an alien foal. Management of maternal behavior problem cases in which the pair cannot be salvaged include foster (or nurse mares) and hand-rearing methods. Also presented are current practical resources related to managing certain types of inadequate maternal behavior and for rearing the orphaned foal.
Keywords: Equine; bonding; behavior; mare; neonatal; foal; inadequate maternal behavior; orphan foal; nurse or foster mare
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Verrill, S., & McDonnell, S. (2008). Equal Outcomes with and without Human-to-Horse Eye Contact When Catching Horses and Ponies in an Open Pasture. Journal of Equine Veterinary Science, 28(5), 309–312.
Abstract: Each of 104 horses and ponies was approached for catching at pasture by the same human handler in a standard manner, either maintaining human-to-animal eye contact (EC+; n = 51) or avoiding eye contact (EC-; n = 53). A subset of 74 of these subjects were reevaluated 3 weeks later under similar standard conditions except with the eye contact condition opposite to that used in the first round. Nonparametric statistical methods were used to evaluate between subjects (round 1, n = 104) and within subjects (rounds 1 and 2, n = 74) comparisons of successful or unsuccessful catching outcome with EC+ and EC-. Catching outcomes were similar with eye contact condition. Although this study represents a single handler at one study site, results suggest that human-to-horse eye contact may not be an important influence on catching pastured horses. Certainly, further work is needed to better understand the role of eye contact in horse handling.
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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 |