Abstract: Ziel der Studie war die Beschreibung der motorischen Lateralität („Schiefe“) gesunder adulter Pferde. Hierzu wurden 14 lahmfreie Pferde (10 Warmblüter, 4 Quarter Horses) auf dem Laufband in Schritt und Trab auf individuelle Abweichungen von der symmetri-schen Bewegung hinsichtlich Abstellung der Hinterhand, Wirbelsäulenform (Biegung), Vor- und Rückführung sowie Belastung von Vorder- und Hintergliedmaßen jeweils simul-tan hochfrequenzkinematographisch und kinetisch mittels resistiver Hufdrucksensoren untersucht. Zusätzlich wurden bevorzugte Abstellung und Biegung sowie Galopppräfe-renz klinisch bzw. reiterlich beurteilt, das Vorliegen einer Weideschrittpräferenz unter-sucht und Freilaufversuche (bevorzugte Abbiegerichtung, Ausweichrichtung um ein Hin-dernis, Galoppräferenz) durchgeführt. Keines der Pferde zeigte Symmetrie über alle Merkmale; zwar wurde bei jedem Merkmal für einzelne Probanden Symmetrie festgestellt, mit Ausnahme des Galopp-Freilaufver-suchs trat Asymmetrie jedoch häufiger auf. 12 Probanden zeigten in der Bewegungsana-lyse eine signifikante seitliche Abstellung (8x rechts (R), 4x links (L), mittlere seitliche Abweichung im Schritt 1,22°±1,09°, im Trab 1,05°±1,03°), 10 eine bevorzugte Biegung (9x L, 1x R), 13 signifikante Asymmetrien der Gliedmaßenvor- bzw. -rückführung und 12 eine signifikante asymmetrische Gliedmaßenbelastung für die normalisierte Spitzenkraft (PFN, peak force) bzw. den Impuls der Belastung (IN) an mindestens einem Beinpaar (alle Merkmale individuell wiederholbar). Linksabgestellte Pferde führten in beiden Gang-arten das rechte Hinterbein signifikant weiter zurück als nach rechts abgestellte Pferde, die tendenziell eher das linke Hinterbein weiter zurückführten. – Die auf dem Laufband festgestellten Asymmetrien traten in beiden Gangarten auf, aber nicht immer überein-stimmend, wobei die Richtung der bevorzugten Abstellung und ebenso der bevorzugten Biegung beim einzelnen Pferd in Schritt und Trab nie gegensätzlich waren. Jeder dieser beiden Parameter wurde daher für das einzelne Pferd über beide Gangarten zusammen-gefasst. Die Richtung von Abstellung und Biegung waren voneinander unabhängig, so-dass die Bewegungsmuster Abstellung ohne Biegung, Biegung ohne Abstellung, Abstel-lung mit Biegung in Laufrichtung (Travers) sowie Abstellung mit Biegung entgegen der Laufrichtung (Schulterherein) vorkamen. Kein Pferd war in beiden Merkmalen symmet-risch; für manche Pferde war neben der einfachen Biegung auch eine S-Form der Wir-belsäule signifikant. Die Belastungssymmetrie der Gliedmaßen war in beiden Gangarten von der Abstellung und der Biegung unabhängig, es gab aber Hinweise auf Zusammen-hänge zwischen bestimmten Kombinationen von Abstellung und Biegung einerseits und der Existenz einer Belastungsasymmetrie der Vorderbeine im Trab andererseits (unge-bogen mit Abstellung laufende und im Schulterherein laufende Pferde belasteten i.d.R. asymmetrisch).
8 Pferde wiesen eine signifikante Weideschrittpräferenz auf (5x L, 3x R), die bei ebenso vorhandener seitlicher Abstellung signifkant häufiger auf der der Abstellung abgewandten Seite auftrat. Sie wies keinen Zusammenhang mit der Rückführung der Hinterbeine im Schritt oder im Trab auf. Das Auftreten einer Weideschrittpräferenz war signifikant vom durch Abstellung und Biegung bestimmten Bewegungsmuster abhängig (Auftreten bei Abstellung ohne Biegung und bei Schulterherein, nicht bei Travers oder Biegung ohne Abstellung). Zudem zeigt die Präferenz der Pferde im Weideschritt eine starke Überein-stimmung mit der Belastungssymmetrie der Vorderbeine im Trab (bevorzugt vorgestelltes Bein wird mehr belastet (IN); symmetrische Belastung bei fehlender Präferenz). Im Hindernisversuch hatten 12 von 13 getesteten Probanden eine signifikant bevorzugte Ausweichrichtung (5x L, 7x R); diese war unabhängig von der gemessenen Wirbelsäulenform, lag aber bei Pferden mit seitlicher Abstellung überwiegend auf der Seite der gemessenen Abstellung. Im Abbiegeversuch zeigten 6 von 12 getesteten Probanden eine signifikant bevorzugte Abbiegerichtung (3x L, 3x R), diese war weder von der Abstellungsrichtung noch von der Wirbelsäulenform, der Weideschrittpräferenz oder der Belastungssymmetrie der Vorderbeine im Trab abhängig. Die meisten Pferde zeigten im Freilauf keine signifikante Galopppräferenz (2x L, 11x gerade (N), 1x R), wogegen reiterlich bei den meisten Pferden eine Präferenz festgestellt wurde; beide Beurteilungen stimmten ebenso wie die Beurteilungen verschiedener Reiter nicht miteinander überein. Die gemessene Abstellungsrichtung ließ sich durch visuelle Beobachtung mit hoher Si-cherheit vorhersagen. Die bevorzugte Wirbelsäulenform stimmte nicht mit der reiterlich oder an der Longe festgestellten Biegung überein, wohl aber mit der Seite, auf die die Mähne fällt. Die vorliegende Studie weist nach, dass individuell stabile motorische Lateralität, weitge-hend bestehend aus den den Merkmalen der reiterlich postulierten „Schiefe“, bei gesun-den Pferden in symmetrischen Gangarten besteht und dass zwischen bestimmten Merkmalen vorhersagbare Zusammenhänge bestehen. Daraus ergeben sich wertvolle Schlussfolgerungen für das reiterliche Geraderichten des Pferdes, für das in Übereinstimmung mit der Reitliteratur insbesondere die Lektion Schulterherein geeignet erscheint. Es ist gelungen, für die wesentlichen Merkmale Abstellung, Biegung und Belastungssymmetrie der Vordergliedmaßen im Trab klinische Tests aufzuzeigen, die mit hoher Sicher-heit die Ergebnisse der Bewegungsanalyse vorhersagen können, wobei Rückschlüsse auf weitere asymmetrische Merkmale möglich sind. Die reiterliche Beurteilung von bevor-zugter Biegung und Galopppräferenz scheint jedoch von weiteren Faktoren außer dem Pferd selbst abhängig zu sein und stimmt häufig nicht mit den messbaren Parametern überein. – In dieser Studie wird erstmals eine wissenschaftlich überprüfte und klinisch anwendbare Methode zur umfassenden Analyse der motorischen Lateralität im Sinne der „Schiefe“ eines Pferdes beschrieben.
Summary -“Crookedness“ in the Horse: Symmetry of Motion and Hoof Loading
The purpose of this study was description of motor laterality (in terms of “crookedness“) of sound adult horses. 14 non-lame horses (10 Warmblood horses, 4 Quarter Horses) were examined walking and trotting on a treadmill for individual motion asymmetry concerning keeping the hindlimbs at an angle (hindlimbs not tracking the frontlimbs, “hindquarter angle”), lateroflexion, pro- and retraction of the limbs as well as loading of front- and hindlimbs. High-speed-kinematography and resistive pressure sensors were used simultanously. The horses were also ridden to evaluate preferred lateroflexion and preferred lead in canter. Moving at an angle towards a preferred side was assessed visually. Laterality of grazing stance was tested, as well as preferred turning direction, obstacle avoidance direction and preferred lead in canter while moving unrestrained in an arena. None of the horses moved symetrically over all traits; although there were symmetrical traits with individual horses, asymmetry was more commen (except for the unrestrained preferred lead test). On the treadmill, 12 horses moved with their hindquarters significantly at a angle (8x right (R), 4x left (L), mean lateral angle 1,22°±1,09° at a walk and 1,05°±1,03° at a trot), 10 showed laterality for lateroflexion (9x L, 1x R), 13 had significant asymmetries for protraction and/ or retraction and 12 for loading of contralateral limbs concerning normalized peak force (PFN) and impulse (IN), respectively, of at least one pair of limbs (all with good repeatibility). Horses keeping their hindquarters to the left showed significantly larger retraction of the right hindlimb compared to horses keeping their hindquarters to the right, who tended to further retract the left hindlimb. – Asymmetries found on the treadmill occurred in both gaits but were not always the same in both gaits, though the direction of the hindquarter angle as well as that of the preferred lateroflexion never contradicted each other within the same individual. Therefore, a specific laterality direction of hindquarter angle and lateroflexion could be assigned to each horse. The direction of preferred hindquarter angle and lateroflexion, respectively, were independent of each other so that the movement patterns “hindquarter angle without lateroflexion”, “lateroflexion without hindquarter angle”, “hindquarter angle with lateroflexion to the same side” (hindquarter-in/ travers) and “hindquarter angle with lateroflexion to opposite sides” (shoulder-in) could be found; no horse moved symmetrical for both traits. The lateroflexion of some horses could even be regarded as a double bend. At both gaits, symmetry of limb loading was independent of hindquarter angle as well as lateroflexion, taken seperately; still, there seems to be a relation between certain combinations of hindquarter angle and lateroflexion, on the one side, and the existence or absence of asymmetric loading of the frontlimbs in trot (horses moving with hindquarter angle, but without lateroflexion, and horses moving in shoulder-in mostly had asymmetric frontlimb loading).
238 7. Summary8 horses displayed laterality for a grazing stance (5x L, 3x R); their hindquarter angle, if they showed one, was significantly more often on the opposite side of their advanced frontleg while grazing. The direction of the grazing stance was independent of hindlimb retraction symmetry in either gait. Occurrence of grazing stance laterality significantly depended on the movement pattern consisting of hindquarter angle and lateroflexion (horses moving with a hindquarter angle, but without lateroflexion, and horses moving in shoulder-in mostly showed grazing stance laterality, while horses moving with lateroflexion, but without a hindquarter angle, and horses moving in hindquarter-in did not). Also, grazing stance laterality was highly predictive of the symmetry of frontlimb loading at trot (advanced frontleg has significantly higher impulse (IN) at trot; horses without grazing stance laterality showed symmetrical impulse). 12 of 13 horses displayed laterality for obstacle avoidance direction (5x L, 7x R) that was independent of the individually preferred lateroflexion but if the horses showed a hindquarter angle it was usually to the same side. 6 of 12 horses showed laterality for turning direction (3x L, 3x R) that had no relation to laterality of either hindquarter angle, lateroflexion, grazing stance or frontlimb loading symmetry at trot. Most horses had no significant lead preference in the unrestrained canter test (2x L, 11x no preference (N), 1x R) even though riders assigned a lead preference to most horses; both ratings did not match, as well as the rating between two different riders did not match. The (measured) direction of hindquarter angle was highly predictable by visual asessment. Preferred (measured) lateroflexion did not match the direction of lateroflexion assigned by either rider or on the long line; it was in agreement with the mane side of the horse, though. This study proves that individual and stable motor laterality exists in sound horses in symmetrical gaits, mostly consisting of the traits that are hypothesized as “crookedness” in riding literature. It also shows that predictible relationships exist between certain traits thereof. This knowledge is valuable since it has implications for the training of riding horses for straightness, wherefore especially riding shoulder-in should be helpful. Relatively easy clinical tests could successfully be found that allow well predicting main features of individual horses ́ motor laterality like hindquarter angle, lateroflexion and frontlimb loading symmetry at trot as measured on the treadmill. Some conclusions can also be drawn for other asymmetrical traits. The asessment of preferred lateroflexion and canter lead performed by riders, though, seems to also underlie other influences than the horse itself and failed to be a predictor of the measured traits. – For the first time, a scientifically proven and clinically applicable method of asessing a horses motor laterality in terms of “crookedness” is presented.

Abstract: An individual's positive or negative perspective when judging an ambiguous stimulus (cognitive bias) can be helpful when assessing animal welfare. Emotionality, as expressed in approach or withdrawal behaviour, is linked to brain asymmetry. The predisposition to process information in the left or right brain hemisphere is displayed in motor laterality. The quality of the information being processed is indicated by the sensory laterality. Consequently, it would be quicker and more repeatable to use motor or sensory laterality to evaluate cognitive bias than to perform the conventional judgment bias test. Therefore, the relationship between cognitive bias and motor or sensory laterality was tested. The horses (n = 17) were trained in a discrimination task involving a box that was placed in either a “positive” or “negative” location. To test for cognitive bias, the box was then placed in the middle, between the trained positive and negative location, in an ambiguous location, and the latency to approach the box was evaluated. Results indicated that horses that were more likely to use the right forelimb when moving off from a standing position were more likely to approach the ambiguous box with a shorter latency (generalized linear mixed model, p < 0.01), and therefore displayed a positive cognitive bias (optimistic).

Abstract: Learning through the observation of others allows the transfer of information without the costs incurred during individual trial and error learning. Horses (Equus caballus) are a highly social species, which might be expected to be capable of learning from others, but experimental findings are inconsistent, and potentially confounded by social facilitation effects not related directly to the learning of the task. We refined the methods used in previous equine social learning studies, to examine and distinguish specific social influences on learning of a task: we used predefined group leaders rather than agonistically dominant individuals to demonstrate a detour task to familiar conspecific observers; in addition we had two control groups: a non-observer (true control) and a group with the demonstrator simply present at the goal (social facilitation control). 44 socially kept horses were allocated to one of the three test conditions and took part in five trials each. Success rate, latency and detour direction were recorded. There was no significant difference between the three groups in the likelihood of them succeeding in the task nor latency to succeed; however there was a significant difference in the route chosen by the groups, with the true control choosing the side with the entrance gate significantly more than either the observer group or social facilitation group. Both of the latter two groups chose to go in the same direction relative to themselves, regardless of which side the gate was. Seven out of nine horses in the observer group chose the same direction as their demonstrator every time. Our results show a significant role of social facilitation on detour behaviour and highlight the importance of including adequate controls for simpler cognitive influences on behaviour before claims can be made about the specific learning of motor actions or goal directed behaviour. Social cues may be important to horses if the task is sufficiently challenging and motivationally important, so future work should consider more demanding, but ecologically relevant situations, in order to maximise the potential revelation of social learning effects which do not depend on simple local or stimulus enhancement effects.

Abstract: Summary For humans, facial expressions are important social signals, and how we perceive specific individuals may be influenced by subtle emotional cues that they have given us in past encounters. A wide range of animal species are also capable of discriminating the emotions of others through facial expressions [1, 2, 3, 4, 5], and it is clear that remembering emotional experiences with specific individuals could have clear benefits for social bonding and aggression avoidance when these individuals are encountered again. Although there is evidence that non-human animals are capable of remembering the identity of individuals who have directly harmed them [6, 7], it is not known whether animals can form lasting memories of specific individuals simply by observing subtle emotional expressions that they exhibit on their faces. Here we conducted controlled experiments in which domestic horses were presented with a photograph of an angry or happy human face and several hours later saw the person who had given the expression in a neutral state. Short-term exposure to the facial expression was enough to generate clear differences in subsequent responses to that individual (but not to a different mismatched person), consistent with the past angry expression having been perceived negatively and the happy expression positively. Both humans were blind to the photograph that the horses had seen. Our results provide clear evidence that some non-human animals can effectively eavesdrop on the emotional state cues that humans reveal on a moment-to-moment basis, using their memory of these to guide future interactions with particular individuals.

Abstract: Monitoring of the wolf Canis lupus is a demanding task as it lives in low densities, utilizes vast home ranges and disperses over large areas. These factors make obtaining accurate data about population parameters over the whole distribution area of the species impossible. Thus detailed local studies on socio-spatial organization are essential to calibrate information obtained over a larger area. We applied GPS/GSM telemetry, non-invasive genetic sampling, year-round tracking, camera trapping and howling stimulations to determine the number of family groups, population density and home-range sizes of wolves in the Drawa Forest (DF, western Poland, 2500 km2), an area recently recolonized by the species. Home ranges of three collared male wolves ranged from 321.8 to 420.6 km2 (MCP 100%) and from 187.5 to 277.5 km2 (Kernel 95%), but core areas had a size of 30.5-84.7 km2 (MCP50%) and 35.0-88.8 km2 (Kernel 50%). Mean near neighbour distance between centres of 6 tracked pack homesites was 15.3 km. The number of wolves in DF increased from 14 individuals in 2013/2014 to 30 in 2016/2017. The annual rate of increase varied from 43% in 2014/2015 to 7% in the final year. Population density for the whole study area was relatively low (1.2 indiv./100 km2 in 2016/2017), but densities within territories of two packs studied with telemetry were 1.9 and 1.5 indiv./100 km2. Mean pack size varied between 3.5 and 5.6 individuals, with the largest pack comprising 8 wolves. Mean number of pups observed in summers (June-August) was 4.5. Differences in home range sizes between wolves in western and eastern Poland indicate that results of regional studies cannot be freely extrapolated despite close genetic relationships. Thus, decisions related to management of wolf habitats should be based on intensive local studies.