Abstract: The conflicting results regarding the study of motor laterality in horses may indicate that there does not exist a proper method to assess the degree and the direction of motor bias in these animals. Unfortunately, even less is known about the development of laterality in horses, and to what extent early manipulations can still exert their effects in adulthood. We propose a new method that can be easily applied at a very early age thus avoiding testing adult horses eventually biased by human handling and/or training. Forty-six horses (29 nine-month-old foals and 17 two-year old horses) were handled since birth bilaterally and housed in groups in wide areas. At the time of the analysis, in order to minimize environmental and sensorial disturbances, each horse was tested in a round pen individually or as dyad mother-foal. The ability/inability to properly execute a circle at trot was then recorded, assuming the direction of derailment, i.e. the cutting of the circle, as an indicator of motor bias. From the results of the study it is arguable that motor laterality in horses is acquired over time: in fact foals tested while their mothers were being subjected to longeing showed a higher percentage of ambidextrous animals, while two-year-old horses appeared biased toward the right (p<0.05). Results are discussed in the light of the scientific knowledge about equine biomechanics, taking into account horses' locomotion that leads to the advancement of the body mass through the activation of a kinetic chain that originates from the hindquarters.

Abstract: Maloney, SJ. The relationship between asymmetry and athletic performance: A critical review. J Strength Cond Res 33(9): 2579-2593, 2019--Symmetry may be defined as the quality to demonstrate an exact correspondence of size, shape, and form when split along a given axis. Although it has been widely asserted that the bilateral asymmetries are detrimental to athletic performance, research does not wholly support such an association. Moreover, the research rarely seeks to distinguish between different types of bilateral asymmetry. Fluctuating asymmetries describe bilateral differences in anthropometric attributes, such as nostril width and ear size, and are thought to represent the developmental stability of an organism. There is evidence to suggest that fluctuating asymmetries may be related to impaired athletic performance, although contradictory findings have been reported. Sporting asymmetries is a term that may better describe bilateral differences in parameters, such as force output or jump height. These asymmetries are likely to be a function of limb dominance and magnified by long-standing participation within sport. Sporting asymmetries do not seem to carry a clear influence on athletic performance measures. Given the vast discrepancy in the methodologies used by different investigations, further research is warranted. Recent investigations have demonstrated that training interventions can reduce sporting asymmetries and improve performance. However, studies have not sought to determine whether the influence of sporting asymmetry is independent of improvements in neuromuscular parameters. It may be hypothesized that the deficient (weaker) limb has a greater potential for adaptation in comparison to the strong limb and may demonstrate greater responsiveness to training.

Abstract: Ein gutes Tierwohl definiert sich nicht nur durch die Abwesenheit von Stressindikatoren, sondern auch durch das Vorhandensein von Indikatoren, die auf ein gutes Wohlergehen hinweisen. So können stressbedingte Erkrankungen vermieden werden. Zur Bestimmung des Tierwohls bei Pferden wurde daher untersucht, inwieweit sich die sensorische Lateralität (einseitiger Gebrauch von Sinnesorganen) und die motorische Lateralität (einseitiger Gebrauch von Gliedmaßen) als einfach, schnell und kostengünstig zu erhebende Parameter eignen. Hierzu werden neben aktueller Literatur auch die eigenen Untersuchungsergebnisse zusammenfassend dargestellt. Die nach außen sichtbar werdende sensorische und motorische Lateralität sind das Resultat der cerebralen Lateralisierung. Dies beinhaltet nicht nur die Aufgabenteilung beider Gehirnhälften für ein effizienteres Aufnehmen und Speichern von Informationen, sondern sie steht auch in Verbindung mit der Entstehung und Verarbeitung von Emotionen, die maßgeblich am Wohlergehen eines Lebewesens beteiligt sind. Kurzzeitige Stressoren führen zu einer Erregung, die je nach Erfahrungen mit positiven oder negativen Emotionen in Verbindung steht. Emotionen helfen dem Organismus dabei, zu überleben. Andauernde negative Emotionen durch regelmäßige oder anhaltende negative Ereignisse führen zu Stress und reduzieren die Erwartung positiver Ereignisse (negativer cognitive Bias). Das Tier ist im Wohlergehen beeinträchtigt. Jüngst zeigte insbesondere die Messung der motorischen Lateralität Potenzial als Indikator für lang anhaltenden und chronischen Stress, denn gestresste Pferde, deren Stresshormonlevel stark ansteigt, zeigen einen zunehmenden Gebrauch der linken Gliedmaßen über einen längeren Zeitraum. Weiterhin zeigen erste Messungen einen Zusammenhang zwischen einer linksseitigen motorischen Lateralität und einer reduzierten Erwartung positiver Ereignisse (negativer cognitive Bias). Zusammen mit der sensorischen Lateralität, die in einer akuten Stressphase ebenso eine Linksverschiebung zeigt und somit als Indikator für Kurzzeitstress gilt, kann eine generelle, vermehrte Linksseitigkeit auch einen Hinweis auf erhöhte Emotionalität und Stressanfälligkeit sein. Eine sich steigernde Linksseitigkeit bedeutet eine präferierte Informationsverarbeitung durch die rechte Gehirnhälfte, die beispielsweise reaktives Verhalten, starke Emotionen und Stressantworten steuert. Es stellte sich jedoch heraus, dass wie bei allen Stressindikatoren auch in der Lateralitätsmessung ein Vergleichswert aus einer vorangegangenen Messung notwendig ist, denn nur Veränderungen zum häufiger werdenden Gebrauch der linken Seite können auf Stress bei Pferden hindeuten und die parallele Erhebung weiterer Parameter, wie zum Beispiel das Verhalten oder Stresshormone, können die Aussage der Lateralität bekräftigen.

Abstract: This paper describes a method in which horses learn to communicate by touching different neutral visual symbols, in order to tell the handler whether they want to have a blanket on or not. Horses were trained for 10-15min per day, following a training program comprising ten steps in a strategic order. Reward based operant conditioning was used to teach horses to approach and touch a board, and to understand the meaning of three different symbols. Heat and cold challenges were performed to help learning and to check level of understanding. At certain stages, a learning criterion of correct responses for 8-14 successive trials had to be achieved before proceeding. After introducing the free choice situation, on average at training day 11, the horse could choose between a “no change” symbol and the symbol for either “blanket on” or “blanket off” depending on whether the horse already wore a blanket or not. A cut off point for performance or non-performance was set to day 14, and 23/23 horses successfully learned the task within this limit. Horses of warm-blood type needed fewer training days to reach criterion than cold-bloods (P<0.05). Horses were then tested under differing weather conditions. Results show that choices made, i.e. the symbol touched, was not random but dependent on weather. Horses chose to stay without a blanket in nice weather, and they chose to have a blanket on when the weather was wet, windy and cold (χ2=36.67, P<0.005). This indicates that horses both had an understanding of the consequence of their choice on own thermal comfort, and that they successfully had learned to communicate their preference by using the symbols. The method represents a novel tool for studying preferences in horses.

Abstract: Generalist predators are expected to shape their diets according to the local availability of prey species. In turn, the extent of consumption of a prey would be influenced by the number of alternative prey species. We have tested this prediction by considering the wild boar and the grey wolf: two widespread species whose distribution ranges overlap largely in Southern Europe, e.g. in Italy. We have reviewed 16 studies from a total of 21 study areas, to assess whether the absolute frequency of occurrence of wild boar in the wolf diet was influenced by (i) occurrence of the other ungulate species in diet and (ii) the number of available ungulate species. Wild boar turned out to be the main prey of the wolf (49% occurrence, on average), followed by roe deer (24%) and livestock (18%). Occurrence of wild boar in the wolf diet decreased with increasing usage of roe deer, livestock, and to a lower extent, chamois and red deer. The number of prey species did not influence the occurrence of wild boar in the wolf diet. The wild boar is a gregarious, noisy and often locally abundant ungulate, thus easily detectable, to a predator. In turn, the extent of predation on this ungulate may not be influenced so much by the availability of other potential prey. Heavy artificial reductions of wild boar numbers, e.g. through numerical control, may concentrate predation by wolves on alternative prey (e.g. roe deer) and/or livestock, thus increasing conflicts with human activities.