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Duncan, P., Foose, T. J., Gordon, I. J., Gakahu, C. G., & Lloyd, M. (1990). Comparative nutrient extraction from forages by grazing bovids and equids: a test of the nutritional model of equid/bovid competition and coexistence. Oecologia, 84(3), 411–418.
Abstract: Ruminants are unevenly distributed across the range of body sizes observed in herbivorous mammals; among extant East African species they predominate, in numbers and species richness, in the medium body sizes (10-600 kg). The small and the large species are all hind-gut fermenters. Some medium-sized hind-gut fermenters, equid perissodactyls, coexist with the grazing ruminants, principally bovid artiodactyls, in grassland ecosystems. These patterns have been explained by two complementary models based on differences between the digestive physiology of ruminants and hind-gut fermenters. The Demment and Van Soest (1985) model accounts for the absence of ruminants among the small and large species, while the Bell/Janis/Foose model accounts both for the predominance of ruminants, and their co-existence with equids among the medium-sized species (Bell 1971; Janis 1976; Foose 1982). The latter model assumes that the rumen is competitively superior to the hind-gut system on medium quality forages, and that hind-gut fermenters persist because of their ability to eat more, and thus to extract more nutrients per day from high fibre, low quality forages. Data presented here demonstrate that compared to similarly sized grazing ruminants (bovids), hind-gut fermenters (equids) have higher rates of food intake which more than compensate for their lesser ability to digest plant material. As a consequence equids extract more nutrients per day than bovids not only from low quality foods, but from the whole range of forages eaten by animals of this size. Neither of the current nutritional models, nor refinements of them satisfactorily explain the preponderance of the bovids among medium-sized ungulates; alternative hypotheses are presented.
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Wiesner, J., & V. Hegel, G. (1990). Zur Immobilisation von Wildequiden mit STH 2130 und Tiletamin/Zolazepam. Tierärzl Prax, 18, 151–154.
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Visser, E. K., Ellis, A. D., Rijksen, L., Van Reenen, C. G., & VanDierendonck, M. (2008). Effect of training method on response of horses to a human approach test. In IESM 2008.
Abstract: The human-horse relationship forms an essential component in the diversity of todays use of horses. The reactions of horses to interactions with humans are mostly the result of interplay between their own temperament; the temperament and skills of the human and their previous experience – with humans. Moreover, the understanding of the human-horse relationship may improve the welfare of horses and humans. Nowadays, “sympathetic” training methods are gaining tremendous attention of horse owners. In the “sympathetic” training method the focus lies on the use of body language in human-horse communication, as well as respecting the horses natural needs. With 28 horses the effect of a “sympathetic” training method versus a conventional training method on the horse“s response on a human-approach test was studied. Fourteen horses of 3.5 years of age were subjected to a five week training period with a conventional training method, the other fourteen horses were subjected to a ”sympathetic“ training method. The overall frequency of snorting during the human approach tests decreased on average from 4.4 (± 1.1) before the training period to 3.1 (± 0.9) after the training period (both groups). However, there was a significant (p=0.006) difference between training methods: the horses trained in the ”sympathetic“ method decreased snorting by 4.3 (±1.1) while the horses trained in the conventional method increased with 1.5 (±0.9). While horses trained in the conventional method whinnied less in the second human approach test, horses trained in the ”sympathetic“ method whinnied more after the period of training. This difference was found to be significant (p=0.006). Defecating decreased over time, but was not different between training methods. The frequency of touching the unfamiliar handler increased over time for both training methods. The horses trained in a conventional method increased from 1.5 to 2.5 and for the sympathetic trained horses from 1.9 to 3.7. This increase was not significantly different for the training methods. Heart rate showed a minor decrease between the human approach tests (before training period 85.3 bpm, after training period 74.3 bpm) but there were no significant differences between training methods. Similarly, there was a slight increase in heart rate variability (rmssd: from 37.0 to 45.2), but no significant differences between training methods. Overal it was concluded that horses trained with this ”sympathetic“ method tended to be more trustful and less stressful in the presence of an (unfamiliar) human compared to horses trained with a conventional method. This may have been due to reduced stress during horse-human contact in the ”sympathetic" training method used. The long term effects on the welfare of the horses, still needs to be investigated.
Keywords: Horse, training, welfare
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De Pasquale, A., Ingala, A., Innella, G., Luigiano, G., Malara, L., & Panzera, M. (2008). The influence of the enriched environment on the reactivity of the precociously handled foals (Equus caballus L.). In IESM 2008.
Abstract: In a preliminary study, we evaluated the effect of precocious handling (at birth, 10, 30 and 60 days) and enriched environment on foal. Two experimental groups were created:
- 3 foals not handled and stabled in semi-enriched environment (Group A). - 6 foals handled and stabled in an enriched environment (Group B). All nine foals were tested with a novel object test (umbrella) at three months of age, to assess the Heart Rate (HR) values measured by a telemetric heart rate monitor (Polar Horse Trainer), during opening, touching and closing of the umbrella. The statistical analysis carried out by means of the Mann-Whitney test showed lower HR values of the foals of group B (P<0.05). Furthermore we have investigated 10 foals born between 2006 and 2008 to study the influence of enriched environment and precocious handling on behavioural responsiveness. The foals were housed on a farm which ensured an enriched environment and made social intra and interspecific interactions easier, alias autoshaping. They were submitted to: - Handling within 24 hours from birth. - Handling and reactivity test (arena test) executed at 10, 30 and 60 days. The temporal correlation was studied among ages and baseline HR values, using the Spearman"s test, to assess the beginning of neurovegetative HR control. In fact statistically significant differences were obtained (r = -0.431; P<0,02). Temporal values of obtained HR baseline, using the Wilcoxon test, showed lower values at 60 days. The comparison was significant among mean and max baseline HR values of 30 vs 60 and 10 vs 60 (P<0.05), while no differences were observed during the reactivity test. This shows that adequate conditions of management associated to a precocious and continuous handling allow the foals to maintain their natural investigative behaviour disappearing fear and flight reactions. |
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Granquist, S. M., Sigurjónsdóttir, H., & Thórhallsdóttir, A. G. (2008). Social structure and interactions within groups of horses containing a stallion. In IESM 2008.
Abstract: Earlier research indicates that stallions might either prevent social interactions between mares in their
herds directly or indirectly by their presence (Feist and McCullough, 1976; Sigurjonsdottir et al., 2003) The impact of stallions on the social interactions between harem members was studied in 6 groups of Icelandic horses in 2004, 2006 and 2007 for altogether 525 hours. Four of the groups were permanently living together under semi-feral conditions, while two were temporary breeding groups. In addition, temporary and permanent groups were compared and the effect of the stability of the group on the social behaviour of horses was investigated . The results show that stallions seldom intervene directly in social interactions between harem members. However, the hierarchies were less rigid and fewer friendship bonds were found in the groups compared to what has been found in groups without stallions in Iceland. These results give some support to our prediction that the stallion does indirectly suppress social interactions of herd members. The stability of the group was found to affect the aggression rate, since a higher aggression rate was found in the temporary groups compared to the permanent groups. The number of preferred allogrooming partners of the horses was also affected to some extent, as a significantly lower number of allogrooming partners was found in the most unstable group compared to all the other groups. The results have significance for further research in the field of social structure of mammals, and may also be applied in the management of horses and other domestic animals. |
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Jørgensen, G. H. M., Borsheim, L., Mejdell, C. M., & Bøe, K. E. (2008). Social interactions and spacing in horses (Equus caballus) grouped according to gender. In IESM 2008.
Abstract: The aim of this study was to investigate the social behaviour and spacing between horses when grouped according to gender in homogeneous- or heterogeneous groups, and to see if the amount and severity of aggression differed in relation to gender composition.
A total of 66 horses divided in six batches were used. In each batch, horses were allotted into one mare group, one gelding group and one mixed gender group, with most groups consisting of three or four animals. Three batches were performed on Icelandic horses and three batches on riding horses and -ponies. After 4-6 weeks of acclimatisation, a trained observer recorded all social interactions using direct, continuous observation one hour in the morning and one hour in the afternoon for three consecutive days. In addition, the nearest neighbour of each horse was recorded using instantaneous sampling every 10 minutes. The horses were inspected for injuries before grouping, day one after grouping and after 4-6 weeks. Furthermore, a novel object test and a handling test (taking horse out of group) were conducted after the behavioural observations were completed. No significant effect of gender composition was found on social interactions, spacing or injuries. Most of the aggressive interactions recorded were threats, and not aggressive interactions involving physical contact. Aggression seemed to increase with decreased space per animal and more horses per feeding place. Very few injuries were found and most were superficial. Horses showed a low degree of fearfulness in the novel object test and most horses were easy to handle in the “horse out of group test”. In conclusion, gender composition does not seem to have any effect on aggression level, spacing or injuries in social groups of horses. |
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Malara, L., De Pasquale, A., Ingala, A., & Innella, G. (2008). The influence of management on horse behavioural reactivity in therapeutic riding programs. In IESM 2008.
Abstract: We investigated 8 horses in five therapeutic riding centres situated in San Cataldo (Caltanissetta – I), Nicosia (Catania – II), Pellaro (Reggio Calabria – III), San Gregorio (Catania – IV), Niguarda Hospitals (Milan – V). The managements of the animals were of different typologies: Type 1, Type 2 and Type 3. In type 1 the horses were used for therapeutic riding only. Furthermore intra and interspecific social interactions were not allowed. In type 2 the horses played kinetic activities and made social interactions. In type 3 the horses were free in paddock, as intra and interspecific social interactions were allowed. The centre I, with a management of type 1, housed 1 horse (A1); the centre II, with a management of type 2, housed 1 horse (B2); the centre III, with a management of type 1, housed 1 horse (C1); the centre IV, with a management of type 2, housed 2 horses (D2 and E2); the centre V, with a management of type 3, housed 3 horses (F3, G3 and H3). Breeds of horses were: Anglo-Arab (n°1), Avelignese (n°3), Italian Selle (n°3), draught-horse crossbreed (n°1). They were 2 geldings and 6 females. Their ages ranged from 12 to 23 years. We observed a total of 64 patients affected by different pathologies: autism, motory handicap, blindness and deafness, children“s cerebral paralysis, relational problems, mental deficiency, Down”s syndrome.
The horses" behaviour was observed at rest and during therapeutic activities with these patients. The Heart Rate (HR) was used as physiological parameter for an ethological evaluation, measured by a telemetric heart rate monitor (Polar Horse Trainer). Horses were analysed with a reactivity test for emotional homeostasis evaluation, too. Heart rate values were studied with non parametrical statistical analysis methods. Distinct management typologies provided statistically different basal mean values of heart rate (intergroup and intragroup): Type 1 vs Type 2 (P~0.05) and Type 1 vs Type 3 (P<0.05). The comparison of heart rate during therapeutic activities of diverse management showed the following results: A1 vs B2 (P<0.05), B2 vs C1 (P<0.05), Type 1 vs Type 2 (P<0.01). Different managements, both in the same or different typologies, gave significantly diverse results (A1 vs E2: P~0.05; C1 vs E2: P~0.05; B2 vs E2: P~0.05). This study shows that the statistic differences obtained by therapies with autistic patients derive from management conditions of Type 1. In reactivity test there aren"t any significant differences among the three management typologies. However, we recorded strong variation between medium and maximum values of heart rate, especially in Type 1 and Type 2 of management. These high variations of heart rate indicated fear reaction of the horse to new stimuli. This reaction could lead to dangerous accidents for patients during therapeutic activities. Horses used in therapeutic riding programs must be evaluated before this employment. Horse's behaviour can be assessed by an ethological observation and a reactivity test. Furthermore, the horses must be guaranteed welfare conditions and must live in an environment enriched with sensorial stimuli and respectful of their physiological and ethological needs. Keywords: Management; Horses; Therapeutic Riding; Behaviour; Reactivity
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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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King, A. J., & Cowlishaw, G. (2009). Leaders, followers and group decision-making. Commun Integr Biol, 2(2), 147–150.
Abstract: Social animals have to make a multitude of group decisions on a daily basis. At the most basic level, this will involve coordination of activities and travel directions. In groups of insects, birds and fish, much of this 'coordination' can be the result of relatively simple interaction patterns among group members. Such systems are self-organizing, and often do not require specific leaders, or followers. However, in more socially complex groups, achieving collective group action-a consensus-may not be accomplished by simple rules alone. Instead, a consensus may be reached by the averaging of preferences (democracy), or by following the choices of specific leaders (despotism). In this mini-review, we discuss the conditions necessary for despotism in animal groups, and focus upon new studies investigating coordinated actions in primates. We ask how specific leaders arise and why others follow them-providing new insight into the mechanisms of effective leadership in groups characterized by strong social relationships.
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Schmoldt, A., Benthe, H. F., & Haberland, G. (1975). Digitoxin metabolism by rat liver microsomes. Biochem Pharmacol, 24(17), 1639–1641.
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