Abstract: Dominance hierarchies in horses primarily influence priority access to limited resources of any kind, resulting in predictable contest outcomes that potentially minimize aggressive encounters and associated risk of injury. Levels of aggression in group-kept horses under domestic conditions have been reported to be higher than in their feral counterparts but can often be attributed to suboptimal management. Horse owners often express concerns about the risk of injuries occurring in group-kept horses, but these concerns have not been substantiated by empirical investigations. What has not yet been sufficiently addressed are human safety aspects related to approaching and handling group-kept horses. Given horse's natural tendency to synchronize activity to promote group cohesion, questions remain about how group dynamics influence human-horse interactions. Group dynamics influence a variety of management scenarios, ranging from taking a horse out of its social group to the prospect of humans mimicking the horse's social system by taking a putative leadership role and seeking after an alpha position in the dominance hierarchy to achieve compliance. Yet, there is considerable debate about whether the roles horses attain in their social group are of any relevance in their reactions to humans. This article reviews the empirical data on social dynamics in horses, focusing on dominance and leadership theories and the merits of incorporating those concepts into the human-horse context. This will provide a constructive framework for informed debate and valuable guidance for owners managing group-kept horses and for optimizing human-horse interactions.

Abstract: Abstract Herds of ungulates, flocks of birds, swarms of insects and schools of fish move in coordinated groups. Computer models show that only one or very few animals are needed to initiate and direct movement. To investigate initiation mechanisms further, we studied two ways in which movement can be initiated in feral horses: herding, and departure from the group. We examined traits affecting the likelihood of a horse initiating movement i.e. social rank, affiliative relationships, spatial position, and social network. We also investigated whether group members join a movement in dominance rank order. Our results show that whereas herding is exclusive to alpha males, any group member may initiate movement by departure. Social bonds, the number of animals interacted with, and the spatial position were not significantly associated with movement initiation. We did not find movement initiation by departure to be exclusive to any type of individual. Instead we find evidence for a limited form of distributed leadership, with higher ranking animals being followed more often.

Abstract: Abstract The maintenance and development of conservation areas by grazing of large herbivores, such as Przewalski's horses, is common practice. Several nature conservation areas house male bachelor groups of this species. When males are needed for breeding they are removed from the groups, often without considering group compositions and individual social positions. However, alpha animals are needed for ensuring group stability and decision making in potentially dangerous situations in several species. To investigate the role of the alpha male in a bachelor group, we observed the behaviour of five Przewalski's horse males during the enlargement of their enclosure. We analyzed the group's social structure and movement orders, as well as the animals' connectedness, activity budgets, and whether they moved with preferred group members and how factors such as social rank influenced the horses' behaviour. We also investigated the excretion of glucocorticoid metabolites (GCM) via faeces of the horses while exploring a new area as a parameter of glucocorticoid production. Our results show that the alpha male is important for a bachelor group in changing environmental conditions. The alpha male had the highest level of connectedness within the group. When exploring the new environment, its position in the group changed from previously being the last to being the first. Furthermore the whole group behaviour changed when exploring the new area. The stallions showed reduced resting behavior, increased feeding and did not stay close to each other. We found that the excretion of glucocorticoid metabolites of most horses rose only marginally during the first days on the new area while only the alpha male showed a significant increased amount of glucocorticoid production during the first day of the enclosure enlargement.

Abstract: Zusammenfassung
Gegenstand und Ziel Seit 2000 siedelt sich der Wolf in Deutschland wieder an. Mit steigenden Wolfszahlen nehmen die durch Wölfe verursachten Nutztierschäden zu, wobei auch Pferde betroffen sind. Ziel der Studie war es, einen Überblick zu dieser Problematik sowie Lösungsansätze zu geben.
Material und Methoden Anhand einer Literaturrecherche wurden Daten zur Wolfspopulation in Deutschland, wolfsbedingten Schäden sowie Möglichkeiten und Grenzen des Herdenschutzes beim Pferd eruiert. Eine Online-Befragung von Pferdehaltern/-besitzern diente dazu, die tatsächliche und/oder gefühlte Bedrohung durch Wölfe und die daraus resultierenden Auswirkungen auf die Pferdehaltung zu ermitteln.
Ergebnisse Die Literaturrecherche zeigte ein kontinuierliches Anwachsen der Wolfspopulation in den letzten Jahren und insbesondere seit 2016 einen deutlichen Anstieg wolfsverursachter Nutztierschäden, wobei Pferde selten betroffen waren. Bei der Online-Befragung stammte die Hälfte der 574 ausgewerteten Fragebögen aus Brandenburg und Niedersachsen. Den größten Einfluss auf die Gefährdungsbeurteilung eigener Pferde durch die wachsende Wolfspopulation hatte das Wissen der Pferdehalter über Wolfsangriffe im eigenen Landkreis, wobei insbesondere die Aspekte einer Haltung von Jungpferden und Weidegang für die Pferde eine Rolle spielten. 64 % der Befragten gaben an, ihre Pferdehaltung trotz der zunehmenden Wolfspopulation nicht geändert zu haben. Nur 8 von 576 Pferdehaltern gaben amtlich bestätigte Wolfsübergriffe an und 30 hatten einen vermuteten Wolfsschaden amtlichen Stellen nicht gemeldet. Mehr als die Hälfte der Befragten, die Kontakt zu einem Wolfsberater hatten, bezeichneten die Zusammenarbeit als nicht bis wenig zielführend.
Schlussfolgerung und klinische Relevanz Die Zahl amtlich bestätigter Wolfsangriffe auf Pferde ist gering. Durch einen grundsätzlich durchgeführten Gentest bei entsprechendem Verdacht ließen sich diese Zahlen objektivieren. Trotz des Bewusstseins einer zunehmenden Gefährdung von Pferden durch Wölfe unternehmen Pferdehalter überwiegend keine prophylaktischen Schutzmaßnahmen. Die Kommunikation zwischen den für das Wolfsmonitoring zuständigen Behörden und den Pferdehaltern erscheint verbesserungswürdig.
Abstract
Objective Since 2000 the wolf population is reestablishing itself in Germany. In consequence to increasing numbers, livestock damage caused by wolves is on the rise, with horses likewise being affected. The aim of the study was to provide an overview of this challenge and its possible solutions.
Material and methods Based on a literature research, data on the wolf population in Germany, wolf-related damage as well as possibilities and limitations of herd protection for horses were evaluated. An online survey addressed to horse owners/keepers served to determine the actual and/or perceived threat posed by wolves and the resulting effects on horse husbandry.
Results The literature search showed a continuous increase of the wolf population in recent years as well as a significant increase of wolf-caused livestock damage in general especially since 2016; although horses were rarely affected. Half of the 574 evaluated questionnaires were from Brandenburg and Lower Saxony. The greatest influence on the individual risk assessment concerning their own horses by the growing wolf population was the horse owners� knowledge of wolf attacks in their own county. Especially the aspects of keeping young horses as well as pasture keeping played a significant role. 64 % of respondents indicated that they had not changed their horse management practices despite the increasing wolf population. Only 8 of 576 horse owners had reported officially confirmed wolf attacks and 30 respondents had not reported a suspected wolf damage to official agencies. More than half of the respondents who had contact with a wolf advisor described the cooperation as either not or only slightly purposeful.
Conclusion and clinical relevance The number of officially confirmed wolf attacks on horses is low. These numbers could be objectified by a routinely performed genetic test in case of corresponding suspicion. Despite the awareness of an increasing danger of horses by wolves, horse owners mostly do not undertake prophylactic protection measures. The communication between responsible authorities for wolf monitoring and horse owners seems to be in need of improvement.

Abstract: The stimuli that elicit thirst were studied in four ponies. Nineteen hours of water deprivation produced an increase in plasma protein from 67 +/- 0.1 g/litre to 72 +/- 2 g/litre, a mean (+/- se) increase in plasma sodium from 139 +/- 3 to 145 +/- 2 mmol/litre and an increase in plasma osmolality from 297 +/- 1 to 306 +/- 2 mosmol/litre. Undeprived ponies drank 1.5 +/- 0.9 kg/30 mins; 19 h deprived ponies drank 10.2 +/- 2.5 kg/30 mins and corrected the deficits in plasma protein, plasma sodium and plasma osmolality as well as compensating for the water they would have drunk during the deprivation period. In order to determine if an increase in plasma osmolality would stimulate thirst, 250 ml of 15 per cent sodium chloride was infused intravenously. The ponies drank when osmolality increased 3 per cent and when plasma sodium rose from 136 +/- 3 mmol/litre to 143 +/- 3 mmol/litre. Ponies infused with 15 per cent sodium chloride drank 2.9 +/- 0.7 kg; those infused with 0.9 per cent sodium chloride drank 0.7 +/- 0.5 kg. In order to determine if a decrease in plasma volume would stimulate thirst, ponies were injected with 1 or 2 mg/kg bodyweight (bwt) frusemide. Plasma protein rose from 68 +/- 2 g/litre pre-injection to 75 +/- 2 g/litre 1 h after 1 mg/kg bwt frusemide and to 81 +/- 1 g/litre 1 h after 2 mg/kg bwt frusemide.(ABSTRACT TRUNCATED AT 250 WORDS)