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Sökning: WFRF:(Hartmann Elke)

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1.
  • Egenvall, Agneta, et al. (författare)
  • Rein tension in harness trotters during on-track exercise
  • 2022
  • Ingår i: Frontiers in Veterinary Science. - : Frontiers Media SA. - 2297-1769. ; 9
  • Tidskriftsartikel (refereegranskat)abstract
    • Horseracing is under public scrutiny with increasing demands to safeguard horse welfare. It is accepted that, as a result of bit pressure and/or equipment, mouth lesions accompany many types of horse use, including racing. However, there are currently no data available on the range of bit pressures in driven trotters. Our aim was to investigate whether rein tension (RT, proxy for bit pressures) differs among gaits, between tempo within gait, between horses and drivers, and between left/right reins. Standardbreds (n = 9), driven by experienced drivers (n = 11), performed exercise tests on a racetrack (cross-over design; total 31 tests, data available from 26 tests). Horses' motion symmetry was measured before tests (trotting in hand). Rein tension, speed and heart rate were measured during exercise. A moving-window filter was applied to RT raw data. Median, maximum and interquartile range for the estimated stride median RT were determined for each rein (left/right) and segment: walk; circling in slow trot followed by transition to faster trot; fast (racing) trot; and slowing down to walk. Mixed models were used for statistical analysis. Least square means for segment median RT ranged between 17–19 N in walk, 34–40 N during circling-accelerating, 51–62 N in fast trot, and 53–71 N for slowing down. Segment maximum RT was between 60–81 N in walk, 104–106 N during circling-accelerating, 72–86 N in fast trot, and 86–129 N during slowing down. Interquartile ranges were between 7–9 N in walk, 28–31 N during circling-accelerating, 8–10 N in fast trot, and 12–18 N for slowing down. Hind limb asymmetry exceeded the recommended threshold in three horses and was associated with higher median (48 N) and maximum (106 N) RT than symmetric horses (29 N and 73 N, respectively, p < 0.01). Consistent left-right asymmetry in RT was more common among horses than among drivers. Rein tension increased with increasing heart rate (p ≤ 0.0006). Rein tensions were higher than those reported during riding or in horses worked from the ground. The findings of high RT, taken together with the high reported prevalence of oral injuries in harness trotters, call for further research into RT, motion symmetry and use of equipment.
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2.
  • Eisersiö, Marie, et al. (författare)
  • Gaping for relief? Rein tension at onset and end of oral behaviors and head movements in unridden horses
  • 2023
  • Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 59, s. 8-14
  • Tidskriftsartikel (refereegranskat)abstract
    • Pressure from the bit in the horse's mouth, rein tension, likely feels unpleasant to the horse due to sen-sitive oral tissues. Through trial and error, the horse may learn how to adjust their behavior in order to avoid, diminish or cease uncomfortable sensations from the bit. We hypothesized that oral behaviors and head movements in response to rein tension have the function to avoid or escape the rein tension. The study objective was to assess in what way oral behaviors and head movements affect rein tension and determine the magnitude of rein tension at the onset and end of these behaviors. Twenty Warm-blood horses were fitted with a bitted bridle and subjected to 8 trials of backing up in response to a rein tension signal with the handler standing next to the horse's withers. The rein tension signal was grad-ually increased and then immediately released when the horse stepped back. A rein tension meter and video recordings were used for data collection. Linear mixed models were used for the statistical analysis. There was a decrease in mean rein tension (sum of left and right rein) from onset to end for open mouth ( P < 0.001, from 19 to 11 Newtons (N), biting on the bit ( P = 0.004, from 11 to 5 N), and head upward ( P = 0.024, from 16 to 12 N), while there was an increase in rein tension associated with head forward ( P = 0.015, from 27 to 37 N) and head downward ( P < 0.001, from 17 to 46 N). Our results suggest that horses will open their mouth, or bite on the bit, to alleviate the oral tissues from pressure; move the head upward to avoid rein tension and move the head forward or downward to increase rein tension, likely in a presumed attempt to break free from the pressure applied. The horse's oral behaviors and head movements during training can be used to gain a greater understanding of how the horse perceives the magnitude of rein tension. (c) 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )
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3.
  • Hartmann, Elke, et al. (författare)
  • 24-h sheltering behaviour of individually kept horses during Swedish summer weather
  • 2015
  • Ingår i: Acta Veterinaria Scandinavica. - : Springer Science and Business Media LLC. - 0044-605X .- 1751-0147. ; 57
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Provision of shelter for horses kept on summer pasture is rarely considered in welfare guidelines, perhaps because the benefits of shelter in warm conditions are poorly documented scientifically. For cattle, shade is a valued resource during summer and can mitigate the adverse effects of warm weather on well-being and performance. We found in a previous study that horses utilized shelters frequently in summer. A shelter with a roof and closed on three sides (shelter A) was preferred and can reduce insect pressure whereas a shelter with roof and open on three sides was not utilized. However, shelter A restricts the all-round view of a horse, which may be important for horses as flight animals. Therefore, we studied whether a shelter with roof, where only the upper half of the rear wall was closed (shelter B), would be utilized while maintaining insect protection properties and satisfying the horses' sense for security. A third shelter was offered with walls but no roof (shelter C) to evaluate whether the roof itself is an important feature from the horse's perspective. Eight Warmblood horses were tested each for 2 days, kept individually for 24 h in two paddocks with access to shelters A and B, or shelters A and C, respectively. Shelter use was recorded continuously during the night (1800-2400 h, 0200-0600 h) and the following day (0900-1600 h), and insect defensive behaviour (e.g., tail swish) in instantaneous scan samples at 5-min intervals during daytime.Results: Seven horses used both shelters A and B, but when given the choice between shelters A and C, shelter C was scarcely visited. There was no difference in duration of shelter use between night (105.8 +/- 53.6 min) and day (100.8 +/- 53.8, P = 0.829). Daytime shelter use had a significant effect on insect defensive behaviours (P = 0.027). The probability of performing these behaviours was lowest when horses used shelter A compared to being outside (P = 0.038).Conclusions: Horses only utilized shelters with a roof whilst a shelter with roof and closed on three sides had the best potential to lower insect disturbance during daytime in summer.
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4.
  • Hartmann, Elke, et al. (författare)
  • A Nordic survey of management practices and owners' attitudes towards keeping horses in groups
  • 2015
  • Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 93, s. 4564-4574
  • Tidskriftsartikel (refereegranskat)abstract
    • Keeping horses in groups is widely recommended but limited information is available about how this is implemented in practice. The aim of this survey was to describe how horses are kept in the Nordic countries in relation to sex, age, breed, and equestrian discipline and to assess owners' attitudes toward keeping horses in groups. Horse owners in Denmark, Finland, Norway, and Sweden were approached using a web-based questionnaire, which was translated into 4 languages and distributed online via equestrian forums, organizations, and social media. The number of respondents was 3,229, taking care of 17,248 horses. Only 8% of horses were never kept in groups, 47% were permanently grouped for 24 h/d, and 45% were stabled singly but grouped during turnout. Yearlings were most often permanently kept in groups (75%), mares and geldings more commonly during parts of the day (50 and 51%, respectively), and stallions were often kept alone (38%). Icelandic horses were more likely to be permanently kept in groups (36%) than warmbloods (16%) and ponies (15%). Twice as many competition horses (51%) were never grouped compared with horses used for breeding (20%) or leisure purposes (15%). The majority of respondents (86%) strongly agreed that group housing benefits horse welfare and that it is important for horses to have the company of conspecifics (92%). Nevertheless, not all horses were kept in groups, showing that attitudes toward group housing may not necessarily reflect current management. The risk of injury was a concern of many respondents (45%), as was introducing unfamiliar horses into already established groups (40%) and challenges in relation to feeding in groups (44%). Safety of people (23%) and difficulties handling groupkept horses (19%) were regarded as less problematic. Results suggest that the majority of horses have the possibility to freely interact with other horses, either as fulltime members of a group during 24 h/d or during turnout. Future research should address the extent to which being a part-time member of a group affects horse welfare. For permanent group housing to become more widespread, such as it is the case for most farm animals, future research could focus on solving some of the reoccurring problems perceived with keeping horses in groups. The dissemination of evidence-based information on all aspects around keeping horses in groups can ultimately stimulate further positive changes in the management of group-kept horses.
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5.
  • Hartmann, Elke, et al. (författare)
  • Associations between driving rein tensions and drivers’ reports of the behaviour and driveability of Standardbred trotters
  • 2022
  • Ingår i: Applied Animal Behaviour Science. - : Elsevier BV. - 0168-1591 .- 1872-9045. ; 254
  • Tidskriftsartikel (refereegranskat)abstract
    • Effective communication between driver and horse through the reins is essential in harness racing to promote safety and optimise performance. Yet, the magnitudes of rein tension applied to driven horses, particularly Standardbred trotters (ST) are currently poorly understood. This is surprising given the number of reports that speak of mouth lesions after competition and equipment use that give raise to horse welfare concerns. Combining rein tension measurements with behavioural parameters has the potential to characterize “driveability” (as compared to “rideability”, the equivalent industry term for riding horses). Thus, the aims of the current study were: (i) identify how drivers perceive ST's behavioural reactions in response to rein signals when driven on a racetrack, (ii) investigate whether drivers’ subjective appraisals of horses’ behavioural responses align with measured rein tensions (RT), (iii) relate these appraisals to the horses’ perceived driveability (score 1 = poor, 10 = excellent), and (iv) assess whether drivers differ in their scoring of horses’ driveability. Nine ST (5 geldings, 7.8 mean ± 2.1 SE years; 4 mares, 6.8 ± 0.5) were driven by 11 drivers (7 females; 4 males) all of whom were experienced in driving ST. Nine drivers tested three different horses each, and two drivers drove two of the horses. This resulted in 31 test drives involving several segments, each comprising a series of changes of gait and direction of travel. Rein tension meters were used throughout. After each test, drivers were asked to report on their experience of each horse they had just driven and to estimate RT (continuous rating scale from 0 to 50 kg) while driving that horse. Overall, segment had a significant effect on median RT (P < 0.001), with RT rising significantly in racing trot (average 59 N; Trot Left/Trot Right) than trotting on a circle (23 N; Circle Left/Circle Right) and walking (8 N), and was higher in counter-clockwise than in clockwise direction in racing trot (P = 0.058). Furthermore, there was an alignment between recorded RT and drivers’ estimates of perceived RT (P < 0.001), and driveability scores increased when estimated RT increased. The current study has confirmed that rein tensiometry may have a place in providing an evidence-base for consistent rein use, especially when horses are driven by multiple drivers. Whether or not soft tissue damage after competitive racing is correlated to higher peak RT, caused by the use of harsher equipment, or a combination of both, merits further investigation.
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6.
  • Hartmann, Elke, et al. (författare)
  • Comparison of 3 methods for mixing unfamiliar horses (Equus caballus)
  • 2011
  • Ingår i: Journal of Veterinary Behavior: Clinical Applications and Research. - : Elsevier BV. - 1558-7878 .- 1878-7517. ; 6, s. 39-49
  • Tidskriftsartikel (refereegranskat)abstract
    • Horses are likely to exhibit aggression when meeting for the first time. Therefore, this study compared 3 methods for mixing horses to evaluate their effectiveness in reducing aggressive interactions: (1) mixing pairs of horses in a paddock (P, 10 minutes, 15 tests), (2) introducing 1 unfamiliar horse to a pair of familiar, resident horses in a paddock (PP, 10 minutes, 15 tests), (3) allowing limited physical contact between pairs of horses for a short period of pre-exposure in neighboring boxes (B, 5 minutes, 16 tests) before mixing them in a paddock (BP, 10 minutes 16 tests). A total of 16 Swedish Standardbred mares, aged 6-18 years (mean age ± SD: 11 ± 4.4), were included in the study. Half of the horses were familiar with each other (resident horses, n = 8), whereas the other half were bought in from a variety of sources (unfamiliar horses, n = 8). Social interactions, consisting of behaviors from the sender, the receiver, and the subsequent sender’s response, were recorded continuously as frequencies. There were no differences in the frequencies of aggressive behaviors between the 3 mixing methods, including those aggressive behaviors in which physical contact had been attempted (kick, strike). Although resident horses were overall more aggressive (median number of aggressive behaviors per horse, 62; Q1, 36; Q3, 68.5) than unfamiliar horses (median per horse, 4; Q1, 2; Q3, 12.5) during all tests (U = 97, P = 0.003), none of the 62 tests needed to be terminated. Unfamiliar horses did not receive more aggression from resident horses in PP (mean per test ± SD: 5.1 ± 3.1) than in P (mean per test ± SD: 6.4 ± 4.9) (t = 0.63, P = 0.544). However, the behavior “attack” was more frequent in PP (median per test, 2; Q1, 0; Q3, 5) than in P (median per test, 0; Q1, 0; Q3, 1) (U = 282, P = 0.042), and “flee” was more frequent in PP (median per test, 6; Q1, 4; Q3, 8) than in P (median per test, 1; Q1, 0; Q3, 6) (U = 290, P = 0.018). Pre-exposure in boxes did not reduce aggression in BP (median per test, 7; Q1, 4.3; Q3, 11.8) as compared with P (median per test, 6; Q1, 2; Q3, 16) (U = 264, P = 0.767), but during pre-exposure in B tests, horses exchanged more nonaggressive (median per test, 2; Q1, 0.3; Q3, 4) than aggressive (median frequency of aggressive behavior, 0; Q1, 0; Q3, 1) (W = 71, P = 0.013) and mixed interactions (median per test, 0; Q1, 0; Q3, 1) (W = 92, P = 0.016) through the opening. Results suggest mixing an unfamiliar horse with 2 resident horses at the same time instead of one by one may be preferable. In this way, the total aggression received by the unfamiliar horse will potentially be less, even though aggressive interactions may be more intense
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8.
  • Hartmann, Elke, et al. (författare)
  • Daytime shelter use of individually kept horses during Swedish summer
  • 2015
  • Ingår i: Journal of Animal Science. - : Oxford University Press (OUP). - 0021-8812 .- 1525-3163. ; 93, s. 802-810
  • Tidskriftsartikel (refereegranskat)abstract
    • In Sweden, no provision for summer shelter to protect horses from heat and insects is required, although access to shelter for horses kept outdoors 24 h during winter is a requirement. This study investigated horses' daytime shelter-seeking behavior in relation to weather conditions and insect activity during a 2-wk period in summer. Eight Warmblood riding horses had access to 2 shelters of different design to test which shelter design is preferred by horses. Furthermore, rectal and skin temperatures and insect-defensive behavior were measured to test whether horses would benefit from the provision of shade. The horses were kept alone in paddocks for 4 d. During 2 d, horses had access to 2 shelters: 1) open shelter with roof and uncovered sides and 2) closed shelter with roof, wind nets on 2 sides, and opaque plastic opposite the entrance. Weather conditions (ambient temperature, relative humidity, solar radiation, wind speed) were recorded every 10 min. The number of insects (flies, mosquitos) was counted from insect traps placed in each shelter and outside. Behavior (shelter use, insect-defensive behavior, locomotion, grazing) was recorded at 5-min intervals between 0900 to 1200 h and 1300 to 1600 h and rectal and skin temperatures were measured at 0800 h, 1200 h, and 1600 h. Data were analyzed with PROC MIXED and GLIMMIX procedure for Generalized Linear Mixed Models. Ambient temperature ranged from 16 to 25 degrees C (average temperature humidity index 65.7 +/- 1.4). Five horses preferred the closed shelter and were observed inside up to 2.5 h continuously. Greater wind speed decreased the likelihood of observing horses inside the shelter (P < 0.001), as did lower numbers of flies (P < 0.001). The insect-defensive behaviors, skin shiver and ear flick, were performed less frequently when horses were using the closed shelter (P < 0.001), indicating that they were less disturbed by insects. Thirty-minute shelter use had no effect on rectal and skin temperatures (P > 0.05). Results showed that horses made use of shelters during the summer even when weather conditions were moderate. A shelter with roof and covers on 3 sides was preferred over a shelter with roof only and can reduce insect-defensive behavior.
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9.
  • Hartmann, Elke, et al. (författare)
  • Dominance and Leadership: Useful Concepts in Human-Horse Interactions?
  • 2017
  • Ingår i: Journal of Equine Veterinary Science. - : Elsevier BV. - 0737-0806 .- 1542-7412. ; 52, s. 1-9
  • Forskningsöversikt (refereegranskat)abstract
    • Dominance hierarchies in horses primarily influence priority access to limited resources of any kind, resulting in predictable contest outcomes that potentially minimize aggressive encounters and associated risk of injury. Levels of aggression in group-kept horses under domestic conditions have been reported to be higher than in their feral counterparts but can often be attributed to suboptimal management. Horse owners often express concerns about the risk of injuries occurring in group-kept horses, but these concerns have not been substantiated by empirical investigations. What has not yet been sufficiently addressed are human safety aspects related to approaching and handling group-kept horses. Given horse's natural tendency to synchronize activity to promote group cohesion, questions remain about how group dynamics influence human-horse interactions. Group dynamics influence a variety of management scenarios, ranging from taking a horse out of its social group to the prospect of humans mimicking the horse's social system by taking a putative leadership role and seeking after an alpha position in the dominance hierarchy to achieve compliance. Yet, there is considerable debate about whether the roles horses attain in their social group are of any relevance in their reactions to humans. This article reviews the empirical data on social dynamics in horses, focusing on dominance and leadership theories and the merits of incorporating those concepts into the human-horse context. This will provide a constructive framework for informed debate and valuable guidance for owners managing group-kept horses and for optimizing human-horse interactions. (C) 2017 The Authors. Published by Elsevier Inc.
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10.
  • Hartmann, Elke, et al. (författare)
  • Effect of work on body language of ranch horses in Brazil
  • 2020
  • Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 15
  • Tidskriftsartikel (refereegranskat)abstract
    • The horses' responses to exercise are commonly monitored using physiological variables, nonetheless physical and mental states can also be expressed through body language. The aims of this study were: (i) to identify how facial expressions and other behavioural variables change in ranch horses after a routine workday, and (ii) to investigate if these changes can be used as indicators of physical tiredness by relating them to known variables of physical fitness and workload. Fourteen crossbred ranch horses were assessed pre- and post-workday on two farms, recording the body language, physiological and workload variables. Statistical analysis consisted of four stages: (i) comparisons between the sampling times (pre- vs post-workday) using linear mixed-effects models with repeated measures and a paired Wilcoxon test; (ii) selection of the most powerful variables by applying Kaiser-Meyer-Olkin test and principal components analyses (PCA); (iii) evaluations of the relationships within these selected variables utilizing PCA and Spearman rank coefficients; and (iv) identifying a critical level of the most robust behavioural indicators using a non-hierarchical cluster analysis. Results showed that after a workday the horses increased the frequency/duration of body language indicative of resting. They also decreased the frequency/duration of body language indicative of attention and movements to avoid flies. However, some of these behaviours are also shown when horses are in pain, leading us to suggest that some ranch horses were probably experiencing a combination of of tiredness and slight soreness. Of particular interest, because of the ease with which it can be assessed on the farm and generalized to other situations, we suggest that the frequency of shifting weight between the forelegs has potential to be used as an indicator of physical tiredness in horses. The results can also be used in the development of tools to improve the welfare of ranch horses as well as horses used in other activities, although more research is needed to validate this assumption.
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