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Bahloul, K., Pereladova, O. B., Soldatova, N., Fisenko, G., Sidorenko, E., & Sempere, A. J. (2001). Social organization and dispersion of introduced kulans (Equus hemionus kulan) and Przewalski horses (Equus przewalski) in the Bukhara Reserve, Uzbekistan. J. Arid. Environ., 47(3), 309–323.
Abstract: Asiatic wild asses and Przewalski horses initially inhabited steppe, semi-desert and desert areas, but Przewalski horses became extinct in the wild, and kulans disappeared at the beginning of the 20th century, except for a small population in Turkmenistan. The Bukhara Breeding Centre (Uzbekistan) was created in 1976 for reintroduction and conservation of wild ungulate species. In 1977-1978, five kulans (two males and three females), from Barsa-Kelmes island on the Aral sea, were introduced into the reserve. The group increased to 25-30 animals in 1989-1990, when eight Przewalski horses from Moscow and St Petersburg zoos were introduced. We analysed the home ranges, preferred habitats and social interactions of these closely related species during 1995-1998 by seasonal and group composition. Horses and asses formed a reproductive group and a secondary non-reproductive group. The home range of the secondary group was larger than the reproductive group and seemed to be less dependent from the watering places. Przewalski horses were less adapted to semi-desert conditions (both water and vegetation needs) than kulan.
Keywords: Przewalski horses; kulans; Central Asia; home range; behaviour
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Weeks, J. W., Crowell-Davis, S. L., Caudle, A. B., & Heusner, G. L. (2000). Aggression and social spacing in light horse (Equus caballus) mares and foals. Appl. Anim. Behav. Sci., 68(4), 319–337.
Abstract: Aggression and social spacing were studied in 14 light horse mares and their foals living at pasture. Focal samples were collected on each mare-foal dyad for 6 to 10.5 h from 2 months of foal age until weaning at approximately 4 months of age. Observations on foals continued until approximately 6 months of age for 7.5 to 10.5 h per foal. Every 2 min the identities of all individuals within 5 m were recorded. All occurrences of agonistic behavior, and the participants, were recorded during the focal samples. In addition, during feeding of supplemental grain, all occurrences of agonistic behavior by all subjects were recorded. Significant correlations were found between mare rank and the rank of foals both prior to and after weaning. Before weaning, the rank of the foal was significantly correlated with birth order. No significant correlation between birth order and foal rank was found for the post-weaning hierarchy. An animal's gender had no significant effect on foal rank or the choice of preferred associate. Both prior to and after weaning, foals associated preferentially with the foal of their dam's most preferred associate. In addition, significant positive correlations were found between rank of mares and foals and the rate at which they directed aggression to other herd members. (C) 2000 Elsevier Science B.V.
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Schooening, B. (1998). Ethology of the horse. Prakt. Tierarzt, 79(6 Suppl.), 25–28.
Abstract: The paper starts with a short introduction/definition about ethology and the used methods in this scientific field, giving special examples for horses and about how their “normal behaviour” is measured. The behaviour repertoire of horses is described in a brief outline with special emphasis on their social systems and hierarchies and the problem of dominance, especially in interaction with humans. Schlütersche GmbH & Co. KG, Verlag und Druckerei.
Keywords: Dominance; Ethology; Horse; Propedeutics
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Araba, B. D., & Crowell-Davis, S. L. (1994). Dominance relationships and aggression of foals (Equus caballus). Appl. Anim. Behav. Sci., 41(1-2), 1–25.
Abstract: Studied a herd of 15 Belgian brood-mares and 10 foals. Specific aspects of social structure studied were dominance-subordinance relationships, preferred associates, social spacing, aggression rates, the frequency of aggressions administered down the dominance hierarchy, and interactive play bouts. The rank order of the foals, both before and after weaning, was positively correlated with the rank order of their dams. There was also a significant relationship between a foal's rank and its total aggression or aggression rate per subordinate post-weaning. Higher ranking foals had higher rates of aggression. Over 80% of threats were directed down the dominance hierachy. The play-rank order of the foals, scored by the number of times foal left a play bout, was not significantly correlated with the rank order as scored by agonistic interactions. -from Authors
Keywords: aggression; dominance; horse; Equus caballus
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Lehmann, K., Kallweit, E., & Ellendorff, F. (2006). Social hierarchy in exercised and untrained group-housed horses--A brief report. Appl. Anim. Behav. Sci., 96(3-4), 343–347.
Abstract: Changes in social hierarchy were evaluated in a herd of 3-year-old Hanoverian geldings. One group (n = 5) was exposed to a training programme, the other (n = 5) remained untrained. After 6 months, the groups were reversed. Hierarchical positions were evaluated by field observations and/or paired-feeding tests at the beginning, the middle, the end of the first and at the end of the second training period. Both methods yielded identical results. Almost all horses changed position in only one direction: either up or down. Neither increase in aggression nor mutual injuries were recorded during the whole experiment. No statistically verified differences in dominance ranking occurred between trained and untrained groups, but apparent differences were consistent. Thus, if horses are kept in the same group for a longer period of time, exercise induced changes in hierarchy are probably of minor importance and are unlikely to increase the incidence of injuries. This may have implications for the promotion of group-housing for sport horses.
Keywords: Horses; Social hierarchy; Exercise; Group-housing
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Sappington, B. K. F., McCall, C. A., Coleman, D. A., Kuhlers, D. L., & Lishak, R. S. (1997). A preliminary study of the relationship between discrimination reversal learning and performance tasks in yearling and 2-year-old horses. Appl. Anim. Behav. Sci., 53(3), 157–166.
Abstract: A study was conducted to determine the relationship between discrimination reversal learning and performance tasks in horses. Ten yearling and seven 2-year-old mares and geldings of Arabian (n = 4), Quarter Horse (n = 9), and Thoroughbred (n = 4) breeding were given a two-choice discrimination task in which either a black or a white bucket contained a food reward for ten trials per day during 19 test days. The spatial position of the buckets was varied on a random schedule. The rewarded bucket color was reversed each time a subject met criterion of eight correct choices per day for 2 consecutive days. Discrimination reversal testing was followed by 6 days of performance tasks: three crossing a wooden bridge and three jumping an obstacle to reach food and conspecifics, within a maximum allotted time of 15 min day-1. Total reversals attained by the horses were low (x = 1.5 +/- 0.9). All subjects did attain at least one reversal, and six had two or more reversals. No differences (P > .05) were detected between ages or sexes, nor among breeds in discrimination reversal learning or performance test measurements. However, there was a trend towards a breed difference (P <= 0.09) in the mean number of correct responses to the first reversal criterion. Correlations between reversal learning results and performance task results were extremely low, indicating that the discrimination reversal learning test was not useful for predicting success at these performance tasks. Results from the two performance tasks also showed little correlation (r = 0.04, P < 0.91), indicating that horses might not use the same approach when solving the problem of crossing these two obstacles. The overall poor performance of the horses on the discrimination reversal task suggests horses may have difficulty reversing previously learned tasks.
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Hall, C. A., & Cassaday, H. J. (2006). An investigation into the effect of floor colour on the behaviour of the horse. Appl. Anim. Behav. Sci., 99(3-4), 301–314.
Abstract: Adverse reactions of the domestic horse to environmental stimuli can be problematic in training and management. Hesitation and alarm reactions to visual features of the ground can occur in both ridden work and when handling horses. To assess the effect of one visual feature (colour) on the behaviour of the domestic horse, the reactions of 16 riding horses to 8 different coloured mats were recorded. The effect of stimulus position on these reactions was assessed by presenting them in two different positions, either on the ground (where the horses had to walk over them) or against a wall (where the horses walked past them). Each colour/position combination was presented twice in order to assess the effect of previous experience. An alleyway was constructed to allow the horses to be tested unconstrained and freely walking throughout. The time taken to traverse the alleyway and the observed reaction to the colour was recorded. Significant differences in both measures were found in relation to the position of the colour and whether the subject had previous experience of that colour/position combination. The initial presentation of the colours on the ground produced the highest percentage of adverse reactions. Certain colours encountered for the first time on the ground (yellow, white, black and blue) were found to cause a greater number of adverse reactions than others (green, red, brown and grey) and an increase in time taken to traverse the alleyway. Although a significant difference in relation to colour was found in the behaviour observed during the second presentation on the ground, no difference was found in relation to the time taken to traverse the alleyway. No significant effect of colour was found when the coloured stimuli were presented against the wall. These findings have important implications for situations where the colour of flooring could be controlled in order to minimise adverse behavioural reactions, in particular during initial training.
Keywords: Horse; Colour aversion; Flooring; Vision
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Lansade, L., Bertrand, M., & Bouissou, M. - F. (2005). Effects of neonatal handling on subsequent manageability, reactivity and learning ability of foals. Appl. Anim. Behav. Sci., 92(1-2), 143–158.
Abstract: Behaviour is an important factor to be taken into account in the various uses of horses. Today horses are mainly used for sport and leisure activities. They should therefore be easy to manage, calm and not fearful. Early handling is known to improve manageability and learning ability and to reduce fearfulness in various species. It has become fashionable in the horse industry to use an early training procedure, referred to as “imprint training”, which is said to produce durable if not permanent effects. However, no studies concerning the long-term effects of such neonatal handling have been carried out in horses. The present study examines the short- and long-term effects of neonatal handling on manageability, general reactivity and learning ability of foals. Twenty-six Welsh foals were studied: 13 were handled daily for 14 days from birth and 13 were non-handled controls. The handling procedure consisted of fitting a halter, gently patting all parts of each foal's body, picking up feet and leading over 40 m. Two days, 3 months, 6 months and 1 year after the end of the handling period, foals underwent behavioural tests to measure their manageability and various aspects of their reactivity. The results showed that neonatal handling has only short-term effects on manageability: 2 days after the handling period, handled animals were significantly easier to handle than controls for the four parameters measured during this test (time to fit a halter, time to pick up feet, walk ratio that is time during which foal walks under constraint/total time measured during leading and number of defensive reactions). Two parameters (time to fit a halter and walk ratio) were still lower in handled foals than in non-handled foals 3 months later and only one 6 months later (walk ratio). One year later there was no difference between groups. In addition, there was no effect of handling on reactivity at any time of testing or in any of the tests (reaction to isolation from conspecifics, presence of a human, presence of a novel object and to a surprise effect). Finally, neonatal handling did not improve the spatial or discriminative learning abilities measured at 14 months of age. To conclude, the effects of neonatal handling are only temporary.
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Lansade, L., Bertrand, M., Boivin, X., & Bouissou, M. - F. (2004). Effects of handling at weaning on manageability and reactivity of foals. Appl. Anim. Behav. Sci., 87(1-2), 131–149.
Abstract: The horse's temperament, including its manageability and reactivity and/or fearfulness, is of importance as it can result in problems and can render horses unsuitable for inexperienced riders. Early experience, including handling during infancy, may influence the horse's adult behaviour and reduce its fear of humans and other potentially frigthening situations. In the various species studied, handling has generally been undertaken during the neonatal period. The aim of the present study was to test the effects of handling young horses around the time of weaning, a period which has been demonstrated to be effective in increasing ease of handling in cattle and goats. Sixteen Anglo-Arab foals were handled for 12 days either immediately following weaning (early handled: EH) or 21 days later (late handled: LH); eight additional non-handled foals served as controls (C). Handling consisted of haltering, gently petting all parts of the body, picking up feet and leading the foal over 120 m. During handling sessions, EH were easier to handle than LH: time taken to fit them with a halter, to pick up feet, and “walk-ratio” (time walking under constraint/total time walking) were significantly lower for EH. During subsequent tests conducted over 2 days, 4, and 7 months, as well as 10 months and to some extent 18 months after the end of handling period, EH and LH were easier to handle and less reactive than controls, although differences diminished with time. The period following weaning can therefore be qualified as an “optimal period” for handling. Some of the effects persist for at least 18 months.
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Macuda, T., & Timney, B. (1999). Luminance and chromatic discrimination in the horse (Equus caballus). Behav. Process., 44(3), 301–307.
Abstract: Equine colour vision was measured under conditions that minimised the possibility of animals using brightness cues to make chromatic discriminations. In a two-stage study, we first obtained luminance discrimination functions for achromatic targets then tested for chromatic discrimination over a range of target luminances. Horses were trained on a two-choice discrimination task. The positive stimulus was varied in luminance and/or colour using neutral density and broad band colour filters. The negative stimulus appeared as a uniform grey. In the brightness discrimination task, the horses performed well at large luminance differences but their percentage of correct responses declined to near chance levels at differences of less than 0.2 log units. In addition, a decrement in performance was noted at luminance differences of less than 0.2 log units for green and yellow chromatic discrimination functions, suggesting that horses cannot easily discriminate yellow and green from grey. However, the chromatic discrimination functions for red and blue showed that animals performed very well across the full range of target luminances. These results suggest that horses are at least dichromats.
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