|
|
Kaczensky, P., Ganbaatar, O., von Wehrden, H., & Walzer, C. (2008). Przewalski`s horses (Equus ferus przewalskii) and Asiatic wild asses (Equus hemionus): Similar Species, Same Habitat – Same Use? In IESM 2008.
Abstract: Historic overlap zones of wild equids were small in Africa but extensive for Przewalski`s horses and Asiatic wild asses in Asia. Currently the Great Gobi B Strictly Protected Area in SW Mongolia is the only place where sympatric, free-ranging populations of these equids occur. This provides an unique opportunity to examine the co-existence of these little studied species and test the hypothesis that Przewalski`s horses are primarily adapted to mesic steppe habitats, whereas Asiatic wild asses are adapted to arid desert steppes and semi-deserts.
We monitored 9 Przewalski`s horses and 7 wild asses with satellite telemetry and superimposed the data on a habitat map derived from remote sensing (LANDSAT TM & ETM+-data) and ground sample plots. We tested for habitat preferences comparing use and availability with a logistic regression mixed model approach. Individuals were treated as random factors. Factor variables were tested for significant differences in subsequent Tukey post-hoc tests. Przewalski`s horses had non-exclusive home ranges of 152-826 km² and heavily selected for the most productive riparian plant communities. Asiatic wild asses also had non-exclusive home ranges, but with 4,449-6,835 km² they were 10 times larger than those of Przewalski`s horses. Asiatic wild asses seem to use plant communities more or less relative to their availability. Our results provide evidence for two parallel resource selection strategies. Our findings indicate that the Gobi areas provide an edge, rather than an optimal habitat for Przewalski`s horses. This leaves only small and isolated pockets of suitable habitat for future re-introductions. Asiatic wild asses, on the other hand, need access to large tracts of land to cope with the unpredictable resource distribution of the Gobi. Thus, Asiatic wild ass conservation requires a large scale approach.
|
|
|
|
Kavar, T., & Dovc, P. (2008). Domestication of the horse: Genetic relationships between domestic and wild horses. Livestock Science, 116(1-3), 1–14.
Abstract: To date, a large amount of equine genetic data has been obtained regarding (i) extant domestic horses of various breeds from all over the world, (ii) ancient domestic horses, (iii) the extant Przewalski's wild horse, and (iv) the late Pleistocene wild horse from Eurasia and North America. Here, a review of mtDNA and Y chromosome marker analyses is presented in the context of horse domestication. High matrilineal (mtDNA) diversity, which can be found in both extant and ancient (domestic and wild) horses, has suggested that a high number of wild (and tamed) mares were domesticated. Alternatively, Y chromosome marker analysis revealed a single haplotype in all domestic horses analyzed; interestingly even a small population of extant Przewalski's wild horses showed two different Y chromosome haplotypes. It seems that an extreme male population bottleneck occurred due to domestication, while reduction in the female population was only moderate, leaving about 100 distinct haplotypes. For this reason, we speculate that domestication might have started when the appropriate stallion was found or was obtained by selection. Perhaps it had some unusual but special characteristics which could have accelerated the process of domestication. We doubt that only a single Y chromosome haplotype will be found in present-day domestic horses if there are no important differences between the founder stallion/s and the other stallions that were not included in the domestication. In the Eneolithic, tamed and wild mares have probably been spread all over Eurasia, although the number of animals was most likely very low and the populations were limited to a restricted area (e.g., taming centers). Only two subspecies of wild horses (Tarpan and Przewalski's wild horse) have survived up to recently. During the further process of domestication, mares (tamed or wild) were preferentially crossed to stallions having more desirable characteristics. We assume that mares from different regions varied in their morphology due to adaptation to their local environmental conditions. These data might explain rapid expansion of horse populations, as well as their rapid differentiation into various phenotypes during the early phase of domestication.
|
|
|
|
Kharazyan, F., Hassani, A., Ahmadinejad, M., & Houpt, K. A. (2008). The response of horses to predator stimuli. In IESM 2008.
Abstract: It is unknown whether or not wild horses“ instinct has remained during their centuries of taming. The knowledge of this matter gives riders the opportunity of knowing more not only about horse behavior but also about horse and rider safety. In the current research we try to study behavior of the two Iranian horse breed (Asil & Caspian) in confrontation with stimuli from predators. We explored which kind of stimuli (olfactory stimuli accompanied by auditory stimuli) affects horses more. We groupe horses based on breed, sex and age. All horses are adult. The test area is a room that equipped with ventilator, speaker, and other facilities that needs. The time spent in the test area varies between 5 and 20 min .The experiments were designed to investigate behavioral responses (locomotive activity ( standing , walk , trot , and exploration), eliminatory behavior (defecation, urination)) and physiological responses (measure and record of adrenalin dosages in blood samples before and after facing to stimuli and measured blood”s glucose and cortisol too) of horses to novel auditory and olfactory stimuli.
We explored which kind of stimuli(Olfactory stimuli or auditory stimuli) affects horses more. The experiments were carried out under standardized conditions a total of 60 horses (30 Caspian ponies and 30 Asil horses), of different ages.
We investigated how horses respond to two predator animals" (wolf and Iranian leopard) olfactory and auditory stimulus. The olfactory stimuli were: A: Urine /feces stimuli, B: Fur-derived stimuli. And The auditory stimulus were sound of wolf and Iranian Leopard.
|
|
|
|
King, A. J., Douglas, C. M. S., Huchard, E., Isaac, N. J. B., & Cowlishaw, G. (2008). Dominance and affiliation mediate despotism in a social primate. Curr Biol, 18(23), 1833–1838.
Abstract: Group-living animals routinely have to reach a consensus decision and choose between mutually exclusive actions in order to coordinate their activities and benefit from sociality. Theoretical models predict “democratic” rather than “despotic” decisions to be widespread in social vertebrates, because they result in lower “consensus costs”-the costs of an individual foregoing its optimal action to comply with the decision-for the group as a whole. Yet, quantification of consensus costs is entirely lacking, and empirical observations provide strong support for the occurrence of both democratic and despotic decisions in nature. We conducted a foraging experiment on a wild social primate (chacma baboons, Papio ursinus) in order to gain new insights into despotic group decision making. The results show that group foraging decisions were consistently led by the individual who acquired the greatest benefits from those decisions, namely the dominant male. Subordinate group members followed the leader despite considerable consensus costs. Follower behavior was mediated by social ties to the leader, and where these ties were weaker, group fission was more likely to occur. Our findings highlight the importance of leader incentives and social relationships in group decision-making processes and the emergence of despotism.
|
|
|
|
Klingel, H.. (2008). Social Organisation of the Equids. In IESM 2008.
Abstract: Two distinct types of social organisation have evolved in the Equidae. Type 1: In Horse Equus przewalskii, Plains Zebra E. quagga and Mountain Zebra E. zebra the adults live in non-territorial, stable, one-male families and as single bachelors and in bachelor groups. Family stallions have the exclusive mating rights with the mares in their harems. These consist of up to 6 unrelated mares plus their offspring, totalling up to 20 members. Mares stay in their harems until death. Stallions' tenure is from age 5-6 years, i.e. when they succeed in controlling a harem, for close to life time, but are replaced when dead or incapacitated. Harems are stable even in the absence of a stallion, indicating voluntary membership. Adolescent mares leave their parental families to become members of another harem. In Plains Zebra the adolescent mares are abducted, during an oestrus, by suitors who fight the defending family stallion/father. Successful stallions are bachelors who start a family, or family stallions enlarging their harem. Young stallions leave their parental families voluntarily at age 2-3 years and join bachelor stallion groups from where the family stallions are recruited. An individualised dominance hierarchy excists with the stallion in the alpha position. It is based on individual knowledge and recognistion of the members. Type 2: In Grevy's Zebra E. grevyi, African Wild Ass E. africanus and Asiatic Wild Ass E. hemionus adult stallions monopolise territories in which they have the exclusive mating rights. Stallions are tolerant of any conspecifics entering their territory. Bachelor stallions behave subordinately – or fight for the possession of the territory which is a prerequisite for reproduction. Mares join up to form anonymous and unstable groups or herds. The only stable unit is of a mare and her offspring. In Grevy's Zebra mares with foal join preferentially conspecifics of the same soial status, as do mares without foal. Matings take place inside the territory. There is no lasting relationship of the mare with a particular stallion, and the mare may be mated by any stallion whose territory she is visiting. Territories measure up to 10 or more square kilometres, and tenure is for several years. Grevy Zebra territorial owners leave their territories for a few hours to visit a water hole, or for months when grazing and water conditions are below requirements, and re-occupy it upon return, unchallenged. Except for a few small populations, the extant equids live in semi-arid to arid regions where environmental conditions force them to migrate seasonally or opportunistically. The ranges of the various species overlap: Mountain Zebra and Plains Zebra in South Africa and Namibia, Plains Zebra and Grevy's Zebra in Kenya and Ethiopia, Grevy's Zebra and African Wild Ass in Ethiopia, Asiatic Wild Ass and Przewalski Horse in Mongolia andChina. Although, in the overlap zones, individuals of different species are using the same resources like water and grazing simultaneously and next to each other, they rarely make closer contacts. Infanticide has been recorded in captive situations.
|
|
|
|
Knubben, J. M., Fürst, A., Gygax, L., & Stauffacher, M. (2008). Bite and kick injuries in horses: Prevalence, risk factors and prevention. Equine Veterinary Journal, 40(3), 219–223.
Abstract: Reasons for performing study: Studies on the prevalence and predisposing factors of bite and kick injuries in horses have not been reported in a population-based data sample. Objectives: To investigate the prevalence of bite and kick injuries in horses and associated risk factors in a representative sample of horses in Switzerland. Methods: A questionnaire on the incidence of disease and injury, which included the frequency of bite and kick injuries and their association with breed, housing, use and feeding regime, was sent to 2559 horse owners randomly selected throughout Switzerland. Results: The data of 2912 horses with 897 disorders diagnosed by a veterinarian were analysed. There were 231 injuries, 50 (21.6%) caused by a bite or kick from another horse; this number corresponded to 5.6% of all diseases and injuries and concerned only 1.7% of all the horses evaluated. Warmblood, Thoroughbred and Arabian horses had a 4.3 times higher risk of bite or kick injuries than horses of other breeds. Eighteen per cent of injuries were associated with a change in housing management and occurred regardless of whether horses were kept in groups permanently or sporadically. Conclusions and potential relevance: A stable group hierarchy and a housing system that provides adequate space and is adapted to horse-specific behaviour are important factors in prevention and kick and bite injuries.
|
|
|
|
Knubben,, J. M. Knubben, Gygax,, L. Gygax, Auer,, J. Auer, et al. (2008). Häufigkeiten von Erkrankungen und Verletzungen in der Schweizer Pferdepopulation. Schweizer Archiv für Tierheilkunde, 150(8), 399–408.
Abstract: Bei einer für die Schweiz repräsentativ und zufällig ausgewählten Stichprobe von 2912 Pferden und Ponys wurden mittels Fragebogen Daten zum aktuellen Gesundheitszustand und zum Auftreten von Erkrankungen und Verletzungen während der vergangenen 12 Monate erfasst. 718 Pferde (24.7%) wurden im Erfassungszeitraum wegen 897 gesundheitlichen Problemen einem Tierarzt vorgestellt. Orthopädische und traumatische Fälle machten den grössten Anteil aus (41.5%), gefolgt von Erkrankungen des Gastrointestinal- (27.1%) und des Respirationstrakts (14.0%). Die Hälfte der Lahmheiten entstand als unmittelbare Folge einer Verletzung. Die Verletzungen waren assoziiert mit Weidegang/Auslauf (38.1%), Schläge/Bissen durch Artgenossen (21.6%), Stall (7.8%), Gelände (13.4%), Training (3.5%), Wettkampf (3.5%), Transport (3.0%) oder mit anderen Umständen (9.1%). In 26.5% der Kolikfälle wurde im Monat vor der Erkrankung Futterumstellung vorgenommen. Bei den Atmungserkrankungen wurde in 13.8% die gleiche Krankheit auch bei anderen Pferden im Stall diagnostiziert. Bei 8.1% aller Fälle erfolgte eine Operation, 6.7% waren mit einem mehrtägigem Klinikaufenthalt verbunden. Bei 25.6% aller tiermedizinisch diagnostizierten Fälle wurden ergänzend oder ausschliesslich komplementärmedizinische Therapiemethoden eingesetzt.
|
|
|
|
Komárková, M., & Dubcova, J. (2008). Factors affecting suckling behaviour in loose housed domestic horses. In IESM 2008.
Abstract: Suckling, the main part of maternal investment in equids, is crucial for development and social success of the foal. As such it is of great importance in horse breeding. We examined effect of following factors mentioned in literature on behavioural parameters of suckling in loose housed domestic horses: age and sex of the suckling foal, age, parity (primiparous/multiparous), pregnancy (yes/no) and rank of the mother and sex of the foetus if the mother was pregnant. Four variables describing suckling behaviour were modelled: proportion of suckling attempts rejected by the mother, suckling duration, frequency of suckling and proportion of suckling terminated by the mother. Further, suckling terminated by another mare were analyzed. Behavioural observations were conducted at the National Stud Kladruby nad Labem (Czech Republic). Eight groups of loose housed Oldkladruby horse mares with foals were observed from 14 days (in average) after delivery to abrupt weaning (four to six months of age), each foal for 120 days at least. Within two seasons, 10 495 suckling bouts and suckling attempts were observed in 79 foals (32 males, 47 females, mothered by 59 individual mares). Horses were studied with ad libitum sampling for 6 hours per group each 14 days. Dominance status of the mother was assessed using the Clutton-Brock index (Clutton-Brock et al. 1982, Nature 350:178-180), adjusted to the number of mares in each group, and dyadic dominance-submission relationships between all group members (mares) were determined. No significant effect of pregnancy and sex of the foetus on suckling behaviour were found, except the tendency of mothers bearing female foetuses to terminate more suckling. These findings are opposite to literature, where male foetuses were connected with higher rejection rates (Duncan et al. 1984, Anim Behav 32:255-263). However, incidence of suckling attempts rejected by the mother was very low (2.24 %). No effect of pregnancy of the mother could be caused by the stud management; horses are well fed and do not suffer for nutrition stress as horses in the wild may. All variables were negatively affected by increasing foals age (as expected). Neither sex of the suckling foal, nor age of the mother did significantly affect any of the studied variables. The higher dominance rank a mare achieved the higher frequency of other group member suckling she terminated (rs = 0.49, P < 0.0001; Spearman correlation coefficients, PROC CORR, SAS). From suckling terminated by another mare (N = 190), in 93 % (N =177) it is a dominant mare who ends the suckling. Despite these significant results, suckling terminated by another mare were negligible (1.8 % from all observed suckling bouts) and agonistic interactions between dominant and submissive mares seemed not to compromise foal development. In conclusion, in loose housed mares of domestic horse with foals we have found no detrimental effect of any of literally cited factors on suckling behaviour.
|
|
|
|
Krapp, A., Bachmann I., & Troxler, J. (2008). Das Liegeverhalten von Pferden in Gruppenhaltung. In Schweizer Archiv für Tierheilkunde (Vol. 150, pp. 186–187).
Abstract: Erarbeitung eines Lösungsansatzes zur Optimierung
des eingeschränkten Liegeverhaltens rangniedriger
Pferde in Gruppenhaltung
|
|
|
|
Krueger, K. (2008). Social Ecology of Horses. In j. Korb and J. Heinze (Ed.), Ecology of Social Evolution (pp. 195–206). Heidelberg: Springer Verlag.
Abstract: Horses (Equidae ) are believed to clearly demonstrate the links between ecology and social organization. Their social cognitive abilities enable them to succeed in many different environments, including those provided for them by humans, or the ones domestic horses encounter when escaping from their human care takers. Living in groups takes different shapes in equids. Their aggregation and group cohesion can be explained by Hamilton“s selfish herd theory. However, when an individual joins and to which group it joins appears to be an active individual decision depending on predation pressure, intra group harassment and resource availability. The latest research concerning the social knowledge horses display in eavesdropping experiments affirms the need for an extension of simple herd concepts in horses for a cognitive component. Horses obviously realize the social composition of their group and determine their own position in it. The horses exceedingly flexible social behavior demands for explanations about the cognitive mechanisms, which allow them to make individual decisions. ”Ecology conditions like those that favour the evolution of open behavioural programs sometimes also favour the evolution of the beginnings of consciousness, by favouring conscious choice. Or in other words, consciousness originates with the choice that are left open by open behavioural programs." Popper (1977)
|
|
