Abstract: Horses are one-sided, not only on a motor level, but they also prefer to use one eye, ear or nostril over the other under particular circumstances. Horses usually prefer using the left eye to observe novel objects and humans. This preference is more marked in emotional situations and when confronted with unknown persons. Thus the horse’s visual laterality provides a good option for assessing its mental state during training or in human-horse interactions. A strong preference for the left eye may signal that a horse cannot deal with certain training situations or is emotionally affected by a particular person.
Pferde benutzen für die Begutachtung von Objekten und Menschen bevorzugt eine bestimmte Nüster, ein Ohr oder ein Auge. So betrachten die meisten Pferde Objekte und Menschen mit dem linken Auge. Die Lateralitätsforschung erklärt diese sensorische Lateralität mit der Verarbeitung von Informationen unterschiedlicher Qualität in verschiedenen Gehirnhälften und zeigt auf, dass positive und negative emotionale Informationen sowie soziale Sachverhalte mit dem linken Auge aufgenommen und vorwiegend an die rechte Gehirnhälfte weitergegeben werden. In diesem Zusammenhang ermöglicht die visuelle Lateralität, den Gemütszustand des Pferdes im Training und im therapeutischen Fördereinsatz zu erkennen und zu berücksichtigen.

Abstract: Gegenstand und Ziel: Überprüfung der Tiergerechtheit von Abrufstationen
für Kraftfutter und Heu in der Gruppenhaltung von Pferden anhand
ethologischer und physiologischer Parameter im Vergleich zu konventionellen
Fressständen. Material und Methoden: Die Verhaltensbeobachtungen
fanden in 11 bzw. 10 Offenlaufställen mit Abrufstationen
bzw. Fressständen statt. 270 Pferde wurden individuell unterschieden.
Untersuchungsparameter waren: Drohverhalten mit und ohne Verletzungsrisiko,
Meideverhalten, Verdrängung aus dem Fressstand sowie
Herzfrequenz und Integumentverletzungen. In jedem Betrieb erfolgten
kontinuierliche Direktbeobachtungen für je einen 24-Stunden-Tag (Tortenstückverfahren).
Ergebnisse: Im Wartebereich der Abrufautomaten
traten signifikant mehr Drohgesten ohne bzw. mit Verletzungsgefahr je
Pferd und Tag (8,6 bzw. 3,0) auf als im Wartebereich der Fressstände
(3,4 bzw. 0,9). Demgegenüber konnten die Pferde in Abrufstationen
(1,4 Drohgesten je Pferd und Tag) ungestörter fressen als in Fressständen
(3,2 Drohgesten je Pferd und Tag). Insgesamt betrachtet ergab sich
jedoch bei beiden Fütterungssystemen eine geringe Anzahl an sozionegativen
Interaktionen im Bereich der Futtereinrichtungen. Die Herzfrequenz
lag im Warteareal im Durchschnitt im physiologischen Bereich
(44,59 ± 11,73 Schläge/min). Integumentverletzungen im Zusammenhang
mit dem Fütterungssystem traten nicht auf. Der wichtigste Einflussfaktor
auf die Untersuchungskriterien war der Betrieb (Fläche, Konzeption,
Management). Schlussfolgerung: Unter dem Aspekt der Tiergerechtheit
hinsichtlich des Stress- und Verletzungsrisikos durch soziale
Interaktionen eignen sich bei ordnungsgemäßer Gruppenhaltung mit
fachgerechtem Management sowohl Fressstände als auch Abrufstationen
für Pferde im Offenlaufstall.
[Objective: A comparison with regard to animal welfare of feeding
stalls and automatic feeding systems for hay and concentrates in group
housing systems for horses using parameters of ethology and physiology.
Material and method: The observations of animal behaviour took
place in 10 stables with feeding stalls and in 11 stables with automatic
feeding systems. The field around the feeding systems was divided into
three areas with comparable dimensions (waiting area, exit area and
inside of the feeding system). 270 horses were individually observed.
Parameters of research comprised: threatening behaviour with and
without risk of injury, avoiding behaviour, ”chasing away from the feeding
place”, as well as heart rate and injuries of the integument. Every
group of horses was continuously observed for 24 hours. This observation
took place on four different days and comprised six sessions, each
of 4 hours. Results: In the waiting area of the automatic systems there
were significantly more threatening gestures with and without risk of
injuries for each horse and day (8.6 and 3.0, respectively) than in the
waiting area of the feeding stalls. In contrast, the horses could eat more
relaxed in the automatic systems (1.4 threatening gestures for each
horse and day) than in the feeding stalls (3.2 threatening gestures for
each horse and day). All together the number of negative interactions in
the feeding area of both feeding systems was relatively low. The heart
rate was within the physiological range (44,59 ± 11,73 beats/min) in
the waiting area. There were no injuries of the integument in correlation
with the feeding systems. The most important factor of the observation
criteria was the individual group housing system with its different dimension,
conception and management. Conclusion: Under the aspect
of animal welfare both feeding systems are suitable for horses with respect
to the risk of stress and injuries by social interactions and under
the condition of proper group housing with professional management.]

Abstract: Horses are a highly social species living in complex social systems which should require them to memorise and generalise social experiences and distinguish between familiar and unfamiliar conspecifics. In the main part of my thesis I concentrated on the specific conflict situation of a horse being introduced into a new social group, and investigated its behaviour and stress level. Horses were either introduced (1) immediately, (2) after an observation period, or (3) together with an integration horse after an observation period. Additionally, in the second part of my thesis I arranged several experiments to elaborate additional aspects which could affect the behaviour of horses during introductions. In this study I could describe a simplified method for measuring stress through the analysis of faecal GCMs in horses. An enzyme immunoassay (EIA) for 11-oxoaetiocholanolone using 11-oxoaetiocholanolone-17-CMO: BSA (3?,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. The new assay increases the accuracy of the test and lowers the expenses per sample; also storing of samples at room temperature after collection is less critical. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports (chapter 1). Comparing the different introduction techniques, the introduction with an integration horse led to significantly less total interactions and lower levels of aggression than the introduction of single horses, both immediately and after several days of observing the new group. Additionally, by observing the behaviour of the horses during everyday sociality I could develop a formula describing the interrelationship between expected aggression level and enclosure size per horse. The curve takes an exponential shape. Starting from a space allowance of 300 m2 and more per horse, the amount of aggressions per hour approaches zero. For the reduction of aggression levels and injury risks in socially kept horses I recommend an enclosure size of at least 300 m2 per horse (chapter 2). I further investigated the stress level of the introduced animals. Horses which were immediately introduced did not show elevated faecal GCMs. In contrast, horses which were introduced after an observation period had slightly elevated values 2 and 3 days after the introduction. For horses introduced together with an integration horse faecal GCMs were significantly above the baseline value on the day of introduction and 1 day after it. These differences between introduction techniques indicate that the introduction event itself is not as stressful as previously assumed. Rather standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses (chapter 3). In the commentary of chapter 4 several studies are discussed which failed to demonstrate social learning in horses. It is argued that they did not consider important aspects which could have an influence, such as the dominance status or the social background of the horses (chapter 4). In chapter 5 a social feeding situation was investigated. The social rank as well as the position of conspecifics affected the feeding strategy of horses. Domestic horses used social cognition and strategic decision making in order to decide where to feed. When possible they tended to return to the same, continuously supplied feeding site and switched to an ?avoidance tendency? in the presence of dominant horses or when another horse was already feeding there (chapter 5). One possibility to recognize group members is through olfactory recognition. In chapter 6 it is shown that horses are able to distinguish their own from their conspecifics? faeces. In addition, they paid most attention to the faeces of those group members from which they received the highest amount of aggressive behaviour (chapter 6). Horses show cognitive abilities because they are able to use humans as local enhancement cues when searching for food, independently of their body posture or gaze consistency when the persons face them. Moreover, they seem to orientate on the attention of familiar persons more than of unfamiliar persons (chapter 7). Altogether, the results of this thesis provide further support for the view that horses show good conflict resolution strategies. They are perfectly able to deal with the conflict situation of being introduced to new group members, and the introduction event itself is not as stressful as previously assumed. It is rather suggested that standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses. All additional experimental set-ups could demonstrate that horses are well capable of social cognition.

Abstract: Recent research has shown that domestic dogs are particularly good at reading human attentional cues, often outperforming chimpanzees and hand reared wolves [1, 2]. It has been suggested that the close evolutionary relationship between humans and dogs has led to the development of this ability, however very few other species have been studied [3]. We tested the ability of 24 domestic horses to discriminate between an attentive and inattentive person when choosing whom to approach for food. While the attentive person faced forwards, the inattentive person either stood with their body turned 180° away from the subject (body orientation condition), stood with their body facing forwards but their head facing away (head orientation condition) or stood facing forwards but with their eyes closed (eyes closed condition). A fourth, mixed condition was included where the attentive person stood with their body facing away from the subjects but their head turned towards the subject while the inattentive person stood with their body facing the subject but their head turned away. Horses chose the attentive person significantly more often using the body cue (n = 24, k = 19, p = 0.003), the head cue (n = 24, k = 18, p = 0.011), and the eye cue (n = 24, k = 19, p = 0.003) but not the mixed cue (n = 24, k = 13, p = 0.42). In an additional pilot study, horses were tested in an object choice task. A human experimenter cued one of two buckets by either tapping the bucket (tap condition), orienting their body towards the bucket and pointing (body and point condition), pointing while facing forwards (point condition) or orienting their body towards the bucket (body condition). If the subjects chose the correct bucket they were rewarded. Subjects were able to use the tap cue (n = 31, k = 21, p = 0.035), body + point cue (n= 31, k = 21, p = 0.035) and the point cue (n = 30, k = 21, p = 0.021) but not the body cue (n = 31, k = 11, p = 0.076). These results taken together suggest that domestic horses are also very sensitive to human attentional cues, including gaze.
Keywords:
social cognition, animal-human interaction, horses, attention attribution, domestication
1. Hare, B., Brown, M., Williamson, C., and Tomasello, M. (2002). The domestication of social cognition in dogs. Science 298, 1634-1636.
2. Gacsi, M., Miklosi, A., Varga, O., Topal, J., and Csanyi, V. (2004). Are readers of our face readers of our minds` Dogs (Canis familiaris) show situation-dependent recognition of human’s attention. Animal Cognition 7, 144-153.
3. Hare, B., and Tomasello, M. (2005). Human-like social skills in dogs? Trends Cogn. Sci. 9, 439-444.

Abstract: The present study aims to investigate whether the presence of unrelated adult horses at weaning would reduce the social stress of weaning and the emergence of undesirable behaviours. We tested this hypothesis in 32 domestic foals by comparing short and medium term behavioural and physiological responses to weaning in foals maintained in homogeneous groups of peers (PW) to those of foals grouped with both peers and unrelated adults (AW). In total, three trials were conducted, which each trial consisting of one AW group and one PW group. In all foals, weaning was followed by increased vocalization, increased locomotion and increased salivary cortisol concentration. However, signs of stress were less pronounced and shorter in duration in weanlings housed with unrelated adults (e.g. whinnies: p < 0.05; salivary cortisol: p < 0.05). Only foals without adults exhibited increased aggressiveness towards peers (p < 0.05) and abnormal behaviours (p < 0.05) such as excessive wood-chewing and redirected sucking towards peers. In conclusion, introducing adults to minimize weaning stress in foals and later on aggressiveness and abnormal behaviours appears as the most promising approach to date.