Abstract: Ziel der Untersuchung war es, herauszufinden, welche Auswirkungen eine Erhöhung der
Gruppengröße bei Jungpferden auf die Bewegungsaktivität, das Liege- und Sozialverhalten
und die Körperkondition hat. Hierfür wurden insgesamt 42 Pferde im Alter von ein
bis zwei Jahren in Laufstallhaltung in die Untersuchung einbezogen. Die Jungpferde aus
der Bewegungs- und Liegeverhaltensanalyse waren in zwei Kleingruppen (acht und
11 Tiere) und einer Großgruppe (23 Tiere) aufgestallt.
In der Bewegungsaktivität waren deutliche Unterschiede zu erkennen. Es ließ sich ein
positiver Einfluss einer höheren Tierzahl nachweisen, aber kein Einfluss des Alters. Beim
Ruheverhalten konnten höhere Liegezeiten und -frequenzen mit einer Zunahme der
Gruppengröße und eine Abnahme der Liegezeit mit zunehmendem Alter ermittelt werden.
Eine Störung des Liegeverhaltens durch Gruppengrößen, die nicht der natürlichen
Herdenstruktur des Pferdes entsprechen, wurde nicht nachgewiesen. Jedoch hatte die
Haltung der Jährlinge in der großen Gruppe einen Anstieg der repulsiven Verhaltensweisen
zur Konsequenz. Zudem zeigte die Bestimmung des Body Condition Scores
Unterschiede in der Körperkondition bei den Jährlingen der Groß- bzw. der Kleingruppe.
Einem Mangel an Bewegung, der für das Auftreten von Gliedmaßenerkrankungen und
Verhaltensstörungen verantwortlich gemacht wird, kann durch die Haltung von Jungpferden
in großen Gruppen entgegengewirkt werden.
[It is often discussed that the inactivity of horses causes diseases of their musculoskeletal system. Due to these problems the objective of the investigation was to quantify if the size of a group has an effect on the behaviour of young horses. Data from 42 horses in the age of one to two years have been involved in the investigation. The data of two small groups were compared with data of one big group with 23 horses. The movement and lying behaviour of 28 horses were measured with ALT pedometers. The social behaviour of 33 yearlings was documented by direct observation. The results show that the median of the movement time of horses in group A is 82 minutes per day. In group B this increases to a median of 101 and group C reaches the highest median of 149. In the case of lying time an increasing group size leads to a longer duration and a higher frequency of lying, whereas an increase in the age reduces the lying duration. International research studies have shown that keeping of horses in big group husbandry systems is not very common by the owners of horses. In contrast these investigations have shown that horse keeping in big groups has no negative influence on the social behaviour and the Body Condition Score of young horses.]

Abstract: Glucocorticoids or their metabolites can be measured in several body fluids or excreta, including plasma, saliva, urine and faeces. In recent years the measurement of glucocorticoid metabolites (GCMs) in faeces has gained increasing attention, because of its suitability for wild populations. In horses, however, the group-specific enzyme immunoassay described so far has a limited racticability due to its complex extraction procedure. Therefore, we tested the applicability of
other enzyme immunoassays for glucocorticoid metabolites. The present study clearly proved that an enzyme immunoassay (EIA) for 11-oxoetiocholanolone using 11-oxoetiocholanolone-17-CMO: BSA (3α,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. Therefore it was possible to use just a small amount of the supernatant of a methanolic suspension of faeces. The results
correlated well with the already described method for measuring GCMs in horse faeces, i.e. analysing the samples with an EIA after a two step clean up procedure of the samples (Merl et al. 2000). In addition, the 3α,11-oxo-A EIA has the advantage of providing a bigger difference between baseline values and peak values after ACTH stimulation. The new assay increased the accuracy of the test,
lowered the expenses per sample, and storing samples at room temperature after collection was less critical than with other assays investigated in our study. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports and it shows the importance of choosing an assay which is in good accordance with the metabolites excreted in a given species.

Abstract: In most cooperatively breeding birds and mammals, reproductive rates are lower for social subordinates than for dominants, and it is common for reproduction in subordinates to be completely suppressed. Early research conducted in captivity showed that losing fights can increase glucocorticoid (GC) secretion, a general response to stress. Because GCs can suppress reproduction, it has been widely argued that chronic stress might underlie reproductive suppression of social subordinates in cooperative breeders. Contradicting this hypothesis, recent studies of cooperative breeders in the wild show that dominant individuals have elevated GCs more often than do subordinates. The findings that elevated GCs can be a consequence of subordination or a cost of dominance complicate the conventional view of social stress, with broad ramifications for the evolution of dominance and reproductive suppression.

Abstract: Unsteady hand position can cause discomfort to the horse, potentially leading to conflict behaviours (CB) such as head tossing or tail lashing. Some instructors feel that martingales or elastic rein inserts can reduce discomfort caused by inexperienced and unsteady hands. Others consider these devices to be inappropriate [`]crutches'. Four horses and nine riders were tested under three conditions in random order: plain reins, adjustable training martingales (TM), and elasticised rein inserts (RI). Rein-tension data (7 s) and behavioural data (30 s) were collected in each direction. Rein-tension data were collected via strain-gauge transducers. Behavioural data were assessed using an ethogram of defined behaviours. No differences in the number of CB were observed. Mean rein tension for TM was higher than that of RI or controls. Relative to the withers, the head was lower for horses ridden with martingales. Carefully fitted martingales may have a place in riding schools that teach novices.

Abstract: This article examines the recently completed equid ethogram and shows how analogues of social interactions between horses may occur in various human–horse interactions. It discusses how some specific horse–horse interactions have a corresponding horse–human interaction – some of which may be directly beneficial for the horse while others may be unusual or even abnormal. It also shows how correspondent behaviours sometimes become inappropriate because of their duration, consistency or context. One analogue is unlikely to hold true for all horse–human contexts, so when applying any model from horse–horse interactions to human–horse interactions, the limitations of the model may eclipse the intended outcome of the intervention. These limitations are especially likely when the horse is being ridden. Such analyses may help to determine the validity of extrapolating intra-specific interactions to the inter-specific setting, as is advocated by some popular horse-training methods, and highlight the subsequent limitations where humans play the role of the ‘alpha mare’ or leader in horse handling and training. This examination provides a constructive framework for further informed debate and empirical investigation of the critical features of successful intra-specific interactions.