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Zeitler-Feicht, M. H., & Streit, S. (2012). Checkpunkte für eine tiergerechte Fütterung von Pferden an Abrufautomaten. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: In der Offenstallhaltung von Pferden wird für die individuelle Fütterung der Fressstand, der eine art-typische synchrone Nahrungsaufnahme erlaubt, empfohlen (BMELV 2009). Seit einigen Jahren kommen jedoch vermehrt Abrufstationen für Kraft- und Raufutter zum Einsatz. Diese ermöglichen nur ein asynchrones Fressen, was das Risiko für Auseinandersetzungen im Fressbereich erhöht.
In einer repräsentativen Studie an insgesamt 567 individuell unterschiedenen Pferden in 32 Offen-laufställen mit Abrufstationen und 10 Betrieben mit Fressständen wurden die Aufenthaltsdauer und Besuchshäufigkeit sowie das Droh- und Meideverhalten der Pferde im Fütterungsbereich und die Häu-figkeit von Blockaden erfasst, des Weiteren Herzfrequenz und Integumentverletzungen. Fazit war, dass es an den Abrufstationen doppelt so oft zu Auseinandersetzungen kam als an den Fressständen. Als Ursache hierfür konnte die starke Frequentierung der Automaten eruiert werden. Umso wichtiger ist somit die tiergerechte Ausführung der Abrufautomaten. In der Studie konnte nachgewiesen werden, dass Durchlaufstationen pferdegerechter sind als Rücklaufstationen. Als nicht tiergerecht wurden Stationen mit Strom führender Austreibehilfe.eingestuft. Die für das fressende Pferd als verhaltens-gerecht empfohlene Variante (Fressstand mit Eingangssperre und ohne Austreibehilfe) führte zu einer Erhöhung der Besuchshäufigkeit und Aufenthaltsdauer und somit auch zu einer erhöhten Anzahl an Drohgesten je Tier und Tag. Die Herzfrequenz lag im Wartebereich bei den meisten Pferden im physio-logischen Bereich (45,1 ± 12,42 Schläge/min), erhöhte sich jedoch in der Abrufstation um ca. 20 Schlä-ge/min. Einige Tiere zeigten möglicherweise stressbedingt auffallend hohe Herzfrequenzwerte ( 100 Schläge/min). Integumentverletzungen im Zusammenhang mit dem Fütterungssystem traten nicht auf. Das Flächengebot und die Konzeption der Offenstallanlage sowie das Management erwiesen sich als maßgebliche Einflussfaktoren auf alle überprüften Kriterien zur Tiergerechtheit.
Um die Anzahl an Auseinandersetzungen im Fütterungsbereich von Abrufstationen zu mindern wird eine Reduzierung der Fütterungshäufigkeit von üblicherweise bis zu 24 Mahlzeiten auf nur 10 Mahlzeiten empfohlen, gemäß dem natürlichen Fressrhythmus von Pferden. Unabhängig vom Fütterungssystem traten die wenigsten Auseinandersetzungen auf, wenn die Pferde täglich etwa 1,5 kg Heu pro 100 kg Körpermasse erhielten bei zusätzlicher ad Libitum Fütterung von Stroh.
Nach bisherigen Erkenntnissen ergeben sich nachfolgende Checkpoints für Abrufautomaten:
Checkpunkte für Abrufstationen
 Schutz des Pferdes durch Trennwände über die gesamte Körperlänge
 Trennwände mit Sichtkontakt zu den anderen Pferden
 Durchlaufstationen mit separatem Ein- und Ausgang
 Eingangssperre für eine stressfreie Futteraufnahme
 Ausgang mit Pendeltüre und Rücklaufsperre
 Ausgang in einen anderen Funktionsbereich
 Ausreichend Ausweichmöglichkeiten für rangniedere Tiere
 Räumliche Trennung von Kraftfutter- und Heuautomaten
 Maximal je 10 Kraft- und Grobfutterrationen je Tier und Tag
 ≥ 1,5 kg Heu bzw. Heulage pro 100 kg Körpermasse je Pferd und Tag
 Stroh zur freien Verfügung (Möglichkeit zum synchronen Fressen)
 Individuelles Anlernen der Pferde am Automaten erforderlich
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Stucke, D. (2012). Überprüfung der Anwendbarkeit der „Chronopsychobiologischen Regulationsdiagnostik“ (CRD) zur Beurteilung von Belastungssituationen und Bestimmung von Stressreaktionstypen bei Pferden. Ph.D. thesis, Tierärztliche Hochschule Hannover, Hannover.
Abstract: In dieser Untersuchung sollte überprüft werden, ob die für die Stressmessung beim Menschen angewandte „Chronopsychobiologische Regulationsdiagnostik“ (CRD) mithilfe des smardwatch®-Messsystems auch beim Pferd psychische Belastungssituationen aussagekräftig widerspiegelt. Menschen können anhand variierender physiologischer und ethologischer Reaktionen auf Stressoren aus der Umwelt in Stresstypen eingeteilt werden. Auch Pferde reagieren in identischen Situationen ganz unterschiedlich. Es stellte sich daher die Frage, ob Pferde ebenfalls bestimmten Stresstypen zugeordnet werden können.
Mit 26 dreijährigen Hengsten des Landgestüts Celle wurde ein Verhaltenstest durchgeführt. Auf der Grundlage wissenschaftlich dokumentierter und modifizierter Testsituationen (Open-Field-Test, Novel-Object-Test, Startling-Test Objekt/Geräusch, Mensch-Pferd-Interaktion, Ressourcenkontrolle) wurde das Erkundungs- und Fluchtverhalten untersucht (Goslar 2011). Während dieser Belastungssituationen wurden mit dem smardwatch®-Messgerät die elektrophysiologischen Parameter Hautwiderstand, Hautpotential und Muskelaktivität erfasst. Durch eine Zeitreihenmessung dieser physiologischen Parameter konnten die Reaktionen des übergeordneten Reglers (vegetatives Nervensystem) dargestellt werden. Der Hautwiderstand spiegelt die vegetativ-emotionalen Reaktionen wider, das Hautpotential die vegetativ-nervalen und somit laut Balzer (2009) die kognitiven Verarbeitungsweisen, und durch das Elektromyogramm werden die typischen muskulär-motorischen Reaktionen aufgezeichnet. Die vorliegenden Datenzeitreihen wurden mit Hilfe einer biorhythmometrischen Zeitreihenanalyse nach Balzer und Hecht (Hecht 2001, Balzer 2009) ausgewertet. Als Ergebnis wurden chronobiologische Regulationszustände definiert, die dann gemäß dem „Periodischen System der Regulationszustände“ (PSR) (Balzer 2000) eine Beurteilung der psychischen Belastungssituation erlauben. Zur Bestimmung von Stresstypen wurde die Untersuchung nach dem Reiz-Reaktions-Prinzip in drei Phasen unterteilt: Ruhephase, Stressreizphase und Stressverarbeitungsphase. Der Verhaltenstest wurde nach einer Woche zur gleichen Tageszeit mit jedem Hengst einmal wiederholt. Als physiologische Vergleichsparameter wurden vor, während und nach der Belastung insgesamt zehn Speichelproben zur Cortisolbestimmung entnommen.
Die smardwatch®-Messtechnik ist prinzipiell geeignet die physiologischen Parameter Hautwiderstand, Hautpotential und Muskelaktivität auf der Haut des Pferdes aufzunehmen. Durch die biorhythmometrische Zeitreihenanalyse konnten chronobiologische Regulationszustände definiert werden.
Der Verhaltenstest führte bei allen Pferden zu einem signifikanten Anstieg der Cortisolwerte. Ein ebenfalls statistisch gesicherter Unterschied der aktivierten Cortisolwerte zwischen der ersten und zweiten Testwoche zeigt eine geringere Stressreaktion und weist auf einen Lerneffekt der Pferde hin:
Entsprechend der relativen Instabilitäten der Regulation der Körperfunktionen in Messphase 2 und 3 konnten die Pferde in vier Stressregulationstypen (nach Balzer u. Hecht 1996) eingeteilt werden: Stressbeherrscher, -bewältiger und kompensierer sowie Stressnichtbewältiger.
Anhand der Aktivierung von Sympathikus und Parasympathikus konnten zusätzlich vier verschiedene Vegetative Stresstypen unterschieden werden: Sympathikotoniker, Amphotoniker, Indifferenter Typ und Vagotoniker.
Die Cortisolreaktion der Hengste war individuell sehr unterschiedlich. Um die maximalen Anstiege vergleichen zu können, wurde der Trend der jeweiligen Cortisolverlaufskurve bestimmt. Anhand der Trend-korrigierten Cortisolkurven konnten einerseits die relativen Maxima der Cortisolreaktion besser verglichen werden, anderseits konnten die Pferde mittels des unterschiedlichen Trendes in drei Cortisolverlaufsgruppen eingeteilt werden: Tendenz fallend, gleichbleibend oder steigend.
Ein statistischer Nachweis für eine Abhängigkeit zwischen den verschiedenen Stresstypenklassifizierungen konnte anhand der geringen Stichprobenzahl nicht erbracht werden. Jedoch lassen sich Pferde, wie Menschen, unterschiedlichen Stresstypen zuordnen. Schwierig bleibt aber die objektive Beurteilung von Befindlichkeiten, da Empfindungen und Gefühle nur subjektiv wahrnehmbare Qualitäten sind, die von einer Reihe innerer und äußerer Faktoren abhängen. Die Verhaltenszuordnung emotionaler Zustände durch die „Chronopsychobiologische Regulationsdiagnostik“ (CRD) kann nicht ohne die Basis weiterer vergleichender Studien vom Mensch auf das Pferd übertragen werden.
Die CRD-Methode könnte allerdings einen interdisziplinären Ansatz ermöglichen und zukünftig neben den klassischen deskriptiven Verhaltensbeobachtungen bei der Beurteilung von Haltungs- und Umgangssituationen von Tieren wertvolle Aufschlüsse über die Fähigkeit zur Stressbewältigung und deren Konsequenzen für das Wohlbefinden der Tiere geben.
In this study we examined, whether the “Chronopsychobiological regulation diagnosis” (CRD) with the smardwatch®-system which is used to assess specific strain in humans, is also able to reflect convincingly specific strain in horses. Humans can be categorized into so-called stress types, because they react differently in physiology and behaviour to environmental stimuli. Concerning horses, it is also known that individuals react differently in identical situations. The question to be answered is, if it is possible to categorize horses into certain stress types as well.
We carried out a behavioural test with 26 three-year-old stallions of the State Stud of Celle, involving different test situations. On the basis of test situations, well known in scientific literature including slight modifications (open-field-test, novel-object-test, startling-test object/sound, human-horse-interaction, resource control) the explorative and flight behaviour of horses were examined (Goslar 2011). During these situations of strain the system smardwatch® measured the electro-physiological parameters skin resistance, skin potential and muscle activity. With time series analyses of these physiological parameters the reactions of the vegetative nervous system as superior control could be shown. The skin resistance reflects the vegetative-emotional, the skin potential the vegetative-nervous hence according to Balzer (2009) cognitive reactions and the electromyogram shows the motorized reactions. The time series of measured data was analyzed using the biorhythmometrical time series analysis of Balzer and Hecht (Hecht 2001, Balzer 2009). As a result of this, typical states of chronobiological regulation were defined. With the help of the “periodic system of regulatory states” (PSR) (Balzer 2000) these led to a classification of mental stress situations. To categorize horses into stress types the study was devided into three phases according to the stimulus-response principle: phase 1 (relaxing), phase 2 (situation of strain) and phase 3 (stimulus processing phase). The behavioural test was repeated once with each stallion exactly one week later. In addition ten samples of saliva were taken before, during and after the situations of strain from which we determined the cortisol concentration to be compared with the chronopsychobiological parameters.
The smardwatch®-measurement technology is fundamentally suitable to measure the physiological parameters skin resistance, skin potential and electrical muscle activity of horses. Using the biorhythmometrical time series analysis, chronobiological regulatory states could be defined for horses as well.
For each horse the cortisol value increased significantly during the behavioural test. A remarkable difference of the cortisol values assessed in the first and second test, indicates a learning effect: The behavioural test led to a significantly lower stress reaction in the second week.
Depending on the proportions of unstable regulation processes during and after the situations of strain, four types of regulation (Balzer u. Hecht 1996) can be defined: the Control-, Cope-, Compensate- and Non-cope-type.
Using the activation of the sympathetic and parasympathetic nervous system four vegetative stress types could be determined: Sympathicotonic, Amphotonic, Indifferent Type and Vagotonic.
The stress reaction of the stallions in terms of cortisol level was quite individual. To compare the maximum increase the trend of each cortisol trajectory was analyzed. On the one hand correcting for the trend allowed a comparison of relative maxima, on the other hand the horses could be categorized into groups, according to the evolution of their cortisol level (cortisol progression groups): Tendency falling, stable or rising.
The number of samples was not considered to be sufficient in order to statistically assess some dependence among the different classifications of stress types. But to our point of view horses can be assigned to different stress types like humans. But it’s still difficult to judge the emotions of animals, because emotions are subjectively perceptible qualities dependent on many internal and external factors. The assignment of emotional behaviour to the chronopsychobiological regulation diagnosis (CRD) can’t be transferred from human to horse without further studies.
However, the CRD method could enable an interdisciplinary approach. Besides classic descriptive observations of behavior, the CRD could give further information about the coping capacity and the consequences for animal welfare in the assessment of stressful situations.
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Hinrichs, T. (2012). Gruppen Management in Aktiv Ställen. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: In einem Aktivstall leben die Pferde in einer Gruppe und sind im ständigen Sozialkontakt mit ihren Artgenossen. Getrennte Funktionsbereiche kennzeichnen das Konzept. Das Kernstück eines Aktivstalles ist die automatisierte Fütterung für Kraft,- Mineral,- und Raufutter. Sie gewährleistet die bedarfsgerechte Fütterung und regt die Pferde zur vermehrten Bewegungsaktivität an. Die Gestaltung der Funktionsbereiche eines Aktivstalles hängt von mehreren Faktoren wie den örtlichen Gegebenheiten, geplanter Gruppengröße und -zusammensetzung sowie betriebs- und arbeitwirtschaftlichen Aspekten ab.
Die Grundlage für die Planung eines Aktivstall – Konzeptes sind die laufenden Erkenntnisgewinne aus Wissenschaft und Forschung, die praktischen Erfahrungen auf Pferdebetrieben sowie die länderspezifischen, offiziellen Richtlinien und Bestimmungen zur Pferdehaltung.
So sind z. B. in Deutschland die aktuellen Untersuchungen zu den Themen automatisierte Fütterungssysteme und Liegeflächengestaltung im Ruheraum von Frau Dr. Zeitler – Feicht und ihrem Team, den ca. 500 Aktivstallbetrieben und den seit dem Jahr 2009 geltenden Leitlinien zur Pferdehaltung unter Tierschutzgesichtspunkten wesentliche Bestimmungsparameter für die Weiterentwicklung des Aktivstall – Konzeptes.
Auf dem IESM 2012 wird den Teilnehmern das Gruppenmanagement in Aktivställen am Beispiel von Praxisbetrieben vorgestellt. Ziel ist es, eine kontinuierliche Verbesserung der Pferdehaltung im Sinne des Tierschutzes in Verbindung mit der Nutzung der Pferde zu erreichen.
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Stanley, C., & Shultz, S. (2012). Mummy’s Boys: Sex Differential Maternal Offspring Relationships in Semi-feral Horses. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: In polygynous species with high reproductive skew in males, mothers often show differential investment between sons and daughters; however consistent sex differential investment has not been found by previous studies in horses. We investigated sex differences in mother-offspring relationships in nutritionally independent sub-adult semi-feral Carneddau Welsh mountain ponies Equus ferus caballus. Mothers and their sub-adult sons had consistently closer relationships than mothers and daughters. Stronger affiliative bonds between mothers and sons were quantified by their maintenance of closer proximity, higher rates of affiliative interactions and more frequent suckling bouts. These measures of affiliation were temporally associated with higher aggression levels directed towards sub-adults by other band members, particularly stallions. We suggest that aggression may serve as the proximate mechanism driving male dispersal in feral horses and that the stronger mother-son bond signals an attempt to delay their dispersal, highlighting conflict within the band concerning dispersal timing. Since males become increasingly central within the band over time, with mature stallions requiring excellent social skills in order to both acquire and keep a band of mares, we propose that delaying colts' dispersal allows for further development of these skills in a relatively safe environment. This additional investment is expected to maximise their reproductive success. This study illustrates how social network theory can be used to quantify individuals' social experiences, contributing to a greater understanding of the evolution of group living. It also gives us further insight into the mechanisms underlying dispersal in wild and semi-wild horse populations and how conflict often arises when individual needs differ.
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De Giorgio, F., & Schoorl, J. M. (2012). Why isolate during training? Social learning and social cognition applied as training approach for young horses (Equus caballus). In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: In the last decade an increasing number of studies has been oriented towards equine social learning and their social behavior within the herd (Kruger‚ 2006-2008). In social species, social learning is important to learn and gain useful skills to move and live in their own social and environmental context. Group housing has been recognized as an important element to fulfill the physical and behavioral needs of horses, especially their need for social contact (Søndergaard‚ 2011). Still‚ when it comes to horse training, the social aspect and‚ in general‚ cognitive abilities of the horse are rarely taken into account. Although it is widely accepted that social isolation is stressful for horse (Mal et al, 1991a and 1991b) still isolating a young horse is the first step when it comes to training methods. Due to tradition and culture and our performance-oriented society it is both difficult to accept and apply a different social/cognitive training approach. Training sessions are focused on immediate results whereas in cognitive learning part of the process is latent and will not be visible immediately‚ but taking the cognitive skills into account plays an important role in avoiding tension both in the horse as in the human-horse interaction (Baragli and De Giorgio, 2011). In this study we tested the possibility to apply social learning by creating a social environment‚ favoring a cognitive learning approach‚ for the training of six young horses. The group existed in three males and three females, between two and three years old. All six showed initial difficulties and defense to human interaction. They were housed in two groups in adjacent spacious paddocks where they had ample opportunity to move and express their individual and social behavioral repertoire. Each horse had one training session per week without isolating it from the others. The training sessions were held following a cognitive-relational model defined as the equine-zooanthropologic approach (De Giorgio, 2010 – Marchesini, 2011). The learning objectives were to be able to handle each horse‚ conduct it‚ saddle and ride it within a maximum time-frame of two years. Every time a defensive or alert behavior would occur the training activity was re-arranged to not over-pressure the horse. Therefore the persons working with the horses carried out the activities without tight expectations focusing on the horses’ positive attention. After eighteen months all six horses were used to the saddle and to riding. None of the horses ever fled or showed defense behavior and in the case of unexpected events they showed no emotional reactivity/reactive behavior. Today the horses show the same calm behavior whenever worked individually. This preliminary study highlights how social learning applied to equestrian activity can be fundamental for safety and welfare and the establishment of a more problem-free relationship between horse and human. Safety as the defensive behavior seems to have been reduced and welfare as the horses have been trained in a social context without being isolated and thus without being stressed during the training experience.
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Erber, R., Wulf, M., Aurich, J., Becker-Birck, M., Rose-Meierhöfer, S., Möstl, E., et al. (2012). Physiological stress parameters in sport horse mares transferred from group housing to individual stabling. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Initial equestrian training and especially first mounting of a rider are stressful challenges for young horses (1). Most young horses are raised in groups but, in association with equestrian training, they are commonly transferred to individual stabling in loose boxes. Although, in most stables, visual contact with horses in adjacent boxes is possible, separation from the herd might be an additional stressor. We have studied physiological stress parameters, in 3-year-old sport horse mares (n=8), transferred from a group stable with access to a paddock to individual boxes without paddock. Once stabled in the individual boxes, mares underwent a standard training for young horses. Horses had been accustomed to lunging and tolerating a rider on their back several weeks before the study. Mares were studied from 5 days before to 5 days after changing the stable. Cortisol concentration in saliva, locomotion activity (ALT pedometers), heart rate (HR) and HR variability (RMSSD: root mean square of successive beat-to-beat intervals) were determined. We hypothesized that the change of the stable increases cortisol release and is associated with changes in HR and RMSSD and reduced locomotion. Before mares were moved to individual boxes, cortisol concentration showed a pronounced diurnal rhythm with values around 0.6 ng/ ml in the morning and a continuous decrease throughout the day. When the mares were moved to individual boxes, cortisol concentration increased to 1.8±0.2 ng/ml and did not return to baseline values within 6 h (p<0.05 over time). On subsequent days, a diurnal rhythm was re-established but shifted to a higher level than before. Locomotion activity determined by ALT pedometers was increased for some minutes only after mares has been placed in individual boxes but was only slightly higher than during the time mares spent with the group in a paddock. On days 2-5 in individual boxes, locomotion activity was reduced compared to the group stable. HR increased and the HRV variable RMSSD decreased when mares were separated. In conclusion, separating horses during initial training from their group is an additional stressor, although the stress is less pronounced than induced by other social challenges, e.g. weaning of foals (2). When stabled in individual boxes, mares move less than when kept as a group. Horses kept in a group thus appear to exercise themselves freely, such an effect is absent when the animals are kept individually.
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Kampmann, S.: A., Hampson, B.A., & Pollitt, C. C. (2012). Population dynamics of Australian feral horses in a semiarid environment. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Introduction: The feral horse population of Australia is the largest in the world and, in average seasons, increases at a rate of approximately 20% per annum. Recent record rainfall in much of semi-arid Central Australia has led to a population increase in excess of normal rates and this project aimed to document the increase. Uncontrolled feral horse numbers have habitat degradation and horse welfare implications and were the reasons for performing the study. Materials and Methods: The study area was an unmanaged 4,000km2 semi-arid area in Central Australia (Lat 24.50, Long 132.10). The population of feral horses within the study area is estimated to be in excess of 10,000. During an 8 week period at the end of the winter season of 2011, horses were identified by ground searches, movement sensored cameras and from hides positioned at key water holes. The area surveyed represented only a small percentage of the overall habitat. Horses were identified by descriptive features and markings. Where possible, sex and age category were documented. Population growth rate was estimated from the observed sample and was expressed as the number of foals born in the current year, divided by the number of horses older than one year. Results: A total of 1,486 horses were identified and categorised, of which 335 were foals born within the current foaling season. Only 129 juveniles, presumably born in the preceding year, were identified. Of the adult horses, 54% were male and 46% were female. Seventy-four percent of mares (n=452) had a foal at foot and the population growth rate was 29%. Conclusion: With a sustained population growth rate of 29%, this population of feral horses will more than double within 3 years. The high rate of increase is concerning because it will negatively impact on the native fauna and flora and fragile semi-arid ecosystems of Central Australia. In addition the feral horses of the study area have experienced an unusual period of high rainfall and plentiful grazing but a return to normal drought conditions is imminent. Starvation, thirst and death from diminished resources will then be a serious welfare concern for horses. KW -
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Belock, B., Kaiser, L. J., Lavagnino, M., & Clayton, H. M. (2012). Comparison of pressure distribution under a conventional saddle and a treeless saddle at sitting trot. The Veterinary Journal, 193(1), 87–91.
Abstract: It can be a challenge to find a conventional saddle that is a good fit for both horse and rider. An increasing number of riders are purchasing treeless saddles because they are thought to fit a wider range of equine back shapes, but there is only limited research to support this theory. The objective of this study was to compare the total force and pressure distribution patterns on the horse’s back with conventional and treeless saddles. The experimental hypotheses were that the conventional saddle would distribute the force over a larger area with lower mean and maximal pressures than the treeless saddle. Eight horses were ridden by a single rider at sitting trot with conventional and treeless saddles. An electronic pressure mat measured total force, area of saddle contact, maximal pressure and area with mean pressure >11 kPa for 10 strides with each saddle. Univariate ANOVA (P < 0.05) was used to detect differences between saddles. Compared with the treeless saddle, the conventional saddle distributed the rider’s bodyweight over a larger area, had lower mean and maximal pressures and fewer sensors recording mean pressure >11 kPa. These findings suggested that the saddle tree was effective in distributing the weight of the saddle and rider over a larger area and in avoiding localized areas of force concentration.
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Proops, L., & McComb, K. (2012). Cross-modal individual recognition in domestic horses (Equus caballus) extends to familiar humans. Proceedings of the Royal Society B: Biological Sciences, 279(1741), 3131–3138.
Abstract: It has recently been shown that some non-human animals can cross-modally recognize members of their own taxon. What is unclear is just how plastic this recognition system can be. In this study, we investigate whether an animal, the domestic horse, is capable of spontaneous cross-modal recognition of individuals from a morphologically very different species. We also provide the first insights into how cross-modal identity information is processed by examining whether there are hemispheric biases in this important social skill. In our preferential looking paradigm, subjects were presented with two people and playbacks of their voices to determine whether they were able to match the voice with the person. When presented with familiar handlers subjects could match the specific familiar person with the correct familiar voice. Horses were significantly better at performing the matching task when the congruent person was standing on their right, indicating marked hemispheric specialization (left hemisphere bias) in this ability. These results are the first to demonstrate that cross-modal recognition in animals can extend to individuals from phylogenetically very distant species. They also indicate that processes governed by the left hemisphere are central to the cross-modal matching of visual and auditory information from familiar individuals in a naturalistic setting.
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Bartos, L., Bartosova, J., Pluhacek, J., & Sindelarova, J. (2012). Promiscuous behaviour disrupts pregnancy block in domestic horse (Equus caballus) mares: A counterstrategy against possible male infanticide. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: It is a common practice that the domestic horse mare is removed from her home environment and transported elsewhere for mating. After conceiving she is returned back into her home environment and social group, containing often familiar stallions and geldings. If we presume that the behavioural adaptation for infanticide relevant for wild, or free-ranging horses has not be lost in domestication (and it is clear that it remains at least within feral populations), then we may expect that, unless prevented by fencing or other management measures, the dominant males in the home social group may subsequently attempt infanticide. Foetal loss is a common phenomenon in domestic horses, being usually substantially higher than that in other domestic ungulates reaching up to 40%. One adaptive response to infanticide risk in polygynous populations is the Bruce effect. Pregnant females terminate their pregnancies when exposed to a dominant strange male. Our previous studies on plain zebra suggested the possibility of the Bruce effect also in equids. In this study we therefore tested the presumption that the Bruce effect could explain foetal loss in domestic horses. Based on reproduction records from horse breeders, we have recently published that bringing a pregnant mare which had been mated away from home into a vicinity of a familiar male who was not the father of her foetus increased probability of pregnancy disruption (Behav Ecol Sociobiol DOI: 10.1007/s00265-011-1166-6). These mares aborted in 31% of cases, while none of those mated within the home stable aborted. Repeated sexual activity either by a stallion or dominant gelding from the normal home group was observed shortly after the mare came from away-mating. Pregnant mares isolated from home males by a fence were even seen soliciting them over the fence. Therefore, there is probably some other mechanism than the Bruce effect leading to pregnancy block in the mare. We speculate that, once returned to the home “herd”, and introduced to familiar males, mares were more likely to terminate their pregnancy to save energy and avoid likely future infanticidal loss of their progeny by dominant male(s) of the home social group. Additional data has now showed that if a mare was mated away from home and was brought into an environment containing mares only, she was less likely to abort than a mare returning to an environment containing familiar male or males. This further supports our above hypothesis. Supported by AWIN, EU FP7 project No. 266213.
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