Abstract: Noninvasive sampling allows genetic studies of free-ranging animals without the need to capture or even observe them, and thus allows questions to be addressed that cannot be answered using conventional methods. Initially, this sampling strategy promised to exploit fully the existing DNA-based technology for studies in ethology, conservation biology and population genetics. However, recent work now indicates the need for a more cautious approach, which includes quantifying the genotyping error rate. Despite this, many of the difficulties of noninvasive sampling will probably be overcome with improved methodology.

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: 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.]