Abstract: The ability of four horses (Equus caballus) to discriminate coloured (three shades of blue, green, red, and yellow) from grey (neutral density) stimuli, produced by back projected lighting filters, was investigated in a two response forced-choice procedure. Pushes of the lever in front of a coloured screen were occasionally reinforced, pushes of the lever in front of a grey screen were never reinforced. Each colour shade was randomly paired with a grey that was brighter, one that was dimmer, and one that approximately matched the colour in terms of brightness. Each horse experienced the colours in a different order, a new colour was started after 85% correct responses over five consecutive sessions or if accuracy showed no trend over sessions. All horses reached the 85% correct with blue versus grey, three horses did so with both yellow and green versus grey. All were above chance with red versus grey but none reached criterion. Further analysis showed the wavelengths of the green stimuli used overlapped with the yellow. The results are consistent with histological and behavioural studies that suggest that horses are dichromatic. They differ from some earlier data in that they indicate horses can discriminate yellow and blue, but that they may have deficiencies in discriminating red and green.

Abstract: Previous research on the Assateague horses found that high-ranking females had more surviving offspring than low-ranking females. Variance in reproductive success may be the result of a variety of proximate processes that affect sexual behavior such as mate choice and mate competition. A study was done to determine whether patterns of courtship, social, and sexual behavior could be identified that would suggest mate choice and/or mate competition. Behavioral data were collected from approximately 40 sexually mature mares living in harem bands. Stallions showed more interest in the eliminations of dominant mares than subordinate mares. Males also engaged in significantly more high-intensity (e.g., mounts and copulations) sexual behavior with dominant mares than subordinate mares, and there was a trend for males to engage in more low-intensity (e.g., flehmen and ano-genital sniffing) sexual behavior with dominant mares than subordinate mares. There was no effect of mare rank on spatial relationships with the stallion; however, dominant mares did attempt to restrict reproductive access to the stallion by harassing and disrupting copulations. Higher foaling rates among dominant mares on Assateague Island could therefore be the result of rank-related mate choice by stallions and direct female competition for mating opportunities.

Abstract: Some animals never exhibit a state that meets the behavioral definition of sleep. Others suspend or greatly reduce ‘sleep’ behavior for many weeks during the postpartum period or during seasonal migrations without any consequent ‘sleep debt.’ Rats die from one form of sleep deprivation, but sleep loss has not been shown to cause death in well-controlled studies in other vertebrate species. Some marine mammal species do not show evidence for REM sleep, and convincing evidence for this state in reptiles, fish and insects is lacking. The enormous variation in the nature of rest and sleep states across the animal kingdom and within the mammalian class has important implications for understanding the evolution and functions of sleep.

Abstract: Rescued equids are often exposed to rehabilitation and training (or retraining) programmes to improve their physical and psychological well-being as well as to facilitate the re-homing process. Training uses either positive or negative reinforcement learning procedures and it is considered here that, there may be welfare implications associated with using the latter technique as it has the potential to overlay acute stress on animals with a chronic stress life history. The aim of this study, therefore, was to compare these training strategies (negative versus positive reinforcement) on equine behaviour and physiology as the first step in establishing an optimal rehabilitation approach (from a welfare perspective) for equids that have been subjected to chronic stress in the form of long-term neglect/cruelty. Over a 7-week period, 16 ponies (aged 6–18 months) were trained using either positive (‘positive’) (n = 8) or negative reinforcement (‘negative’) (n = 8) techniques to lead in hand, stand to be groomed, traverse an obstacle course and load into a trailer. Heart rate was measured (5 s intervals) on days 1 and 4 of each training week, ‘Pre’- (1 h), ‘During’ (0.5 h) and ‘Post’- (1 h) training session. Ethograms (10.00–20.00 h) outside of the training period were also compiled twice weekly. In addition, weekly arena tests (as a measure of reactivity) were also performed 1 week before and during the 7 weeks of training. Results showed significant differences between the two training schedules for some measures during the latter stages of the trial and suggested that animals trained under a positive reinforcement schedule were more motivated to participate in the training sessions and exhibited more exploratory or ‘trial and error’ type behaviours in novel situations/environments. In this context, the incorporation of positive reinforcement schedules within a rehabilitation programme may be of benefit to the animal from a welfare perspective.

Abstract: Pferdehaltungssysteme mit angrenzenden Ausläufen gelten als eine sehr tiergerechte
Haltungsform, da sie den Tieren eine gewisse Bewegungsmöglichkeit
bieten. Ziel der vorliegenden Untersuchung war es, zu erfassen, ob der angrenzende
Auslauf selbst einen ausreichenden Anreiz zur Bewegung darstellt und wie sich verschiedene
Bewegungs- und Platzangebote auf die Bewegungsaktivität von Pferden
in einer Gruppen-Auslaufhaltung auswirken. Zudem wurde ermittelt, welche Auswirkung
die Bewegungsform bzw. –intensität auf das Wohlbefinden der Tiere hat.
Der Großteil der in Deutschland gehaltenen Pferde verbringt die meiste Zeit des
Tages im Stall, obwohl mittlerweile bekannt ist, dass Pferde unter natürlichen
Haltungsbedingungen 12 bis 16 Stunden des Tages in Bewegung verbringen. Der
Optimierung der Stallhaltungssysteme gilt daher ein besonderes Interesse.
Zu diesem Zweck wurden von September 2004 bis Oktober 2005 Versuche mit 24
Warmblutstuten im Alter von 1½ bis 3½ Jahren in Einzel- und Gruppen-
Auslaufhaltungssystemen durchgeführt. Jeweils sechs Pferde bildeten eine Versuchsgruppe.
In jeder Gruppe fanden fünf Varianten von einer ca. dreiwöchigen
Dauer statt. Die Gruppenhaltung wurde dabei durch drei unterschiedliche Zusatzbewegungsangebote
(2 Std. Weide / Tag, 2 Std. unbegrünte Koppel / Tag, 1 Std. Freilauf-
Führanlage / Tag) ergänzt. In der Einzel-Auslaufhaltung (Box mit 45 m²-großem
angrenzenden Auslauf) und in einer Versuchsvariante der Gruppenhaltung bekamen
die Pferde hingegen keine zusätzliche Bewegung außerhalb des Stallhaltungssystems
angeboten. Das Gruppenhaltungssystem selbst war durch die räumliche
Trennung der Funktionsbereiche (Liegen, Fressen, Trinken, Bewegen) gekennzeichnet
und der angrenzende Auslauf war 270 m² groß. In einer zusätzlichen Versuchsphase
fand in der Gruppenhaltung eine Erweiterung des permanent zugänglichen
Auslaufs auf insg. 540 m² statt.
Die Bewegungsaktivität wurde mit Pedometern erfasst, die an jeweils einem Hinterbein
der Pferde befestigt wurden und ergänzend fand eine Analyse von Videoaufzeichnungen
statt. Zur Beurteilung der Stressbelastung fanden Messungen der Herz192
Zusammenfassung
frequenzvariabilität (Parameter HF und SD2) und der fäkalen Cortisolmetabolitenkonzentration
statt.
Die Auswertung des Bewegungsverhaltens ergab, dass eine zusätzliche zweistündige
freie Bewegung der Pferdegruppe auf einer Weide zu einer deutlichen
Steigerung der durchschnittlichen Bewegungsaktivität (149,6 Min. / Tag) führt,
ebenso wie eine einstündige Bewegung in einer Führanlage (173,0 Min. / Tag). Eine
unbegrünte Koppel regte die Pferde der Gruppenhaltung hingegen nicht zu vermehrter
Bewegung an (131,6 Min. / Tag), sondern bewirkte z. T. sogar eine Abnahme
der Bewegungsaktivität. In der Gruppen-Auslaufhaltung ohne zusätzliches Bewegungsangebot
war die Bewegungsaktivität ebenfalls gering (125,8 Min / Tag) und
während der Einzel-Auslaufhaltung ohne Zusatzbewegung zeigten die Pferde die
geringste Bewegungsaktivität (102,3 Min. / Tag).
Bei der alleinigen Analyse der Bewegungszeit im Stallhaltungssystem war kein signifikanter
Einfluss der zusätzlichen Bewegung außerhalb des Stallsystems auf die
übrige Fortbewegung feststellbar.
Auch eine Vergrößerung des an den Stall angrenzenden Auslaufs im Gruppenhaltungssystem
hatte keinen steigernden Einfluss auf das Bewegungsverhalten der
Pferde.
Die Stressbelastung der Pferde war in den Varianten der Gruppenhaltung mit zweistündigem
Weidegang (SD2: 82,9 ms; Cortisolmetaboliten: 29,0 nmol / kg Kot) sowie
der einstündigen Bewegung in einer Freilauf-Führanlage (SD2: 99,2 ms; Cortisolmetaboliten:
27,7 nmol / kg Kot) am geringsten. Die Untersuchungen zeigten eine
Stresszunahme in der Gruppenhaltung mit zweistündigem Auslauf auf einer unbegrünten
Koppel ohne Futterangebot (SD2: 101,3 ms; Cortisolmetaboliten:
39,6 nmol / kg Kot) sowie in der Variante der Gruppenhaltung ohne zusätzliches Bewegungsangebot
(SD2: 113,3 ms; Cortisolmetaboliten: 38,4 nmol / kg Kot). Dem
Mittelwert der Gruppe nach zu folgern hatten die Pferde während der Einzelhaltung
ohne Zusatzbewegung eine sehr große Stressbelastung (SD2: 123,8 ms; Cortisolmetaboliten:
37,5 nmol / kg Kot). Ein Vergleich der Gruppen- und Einzelhaltung hinsichtlich
der Herzfrequenzvariabilität hat jedoch gezeigt, dass insg. 70 % der Pferde
während der Haltung in einer Gruppe weniger Stress empfinden. Es gab aber auch
Zusammenfassung 193
Pferde (30 %), die in der Einzelhaltung eine abnehmende Stressbelastung zeigten,
wobei hier der Einfluss der Rangordnung eine entscheidende Rolle zu spielen
scheint.
Durch die Auswertung mehrerer Messparameter (sowohl für Stress- als auch für Bewegungsverhalten)
werden gleichgerichtete Tendenzen bei den Versuchsvarianten
deutlich, allerdings ist eine eindeutige Gewichtung der Parameter nicht möglich.
Somit ist die methodische Vorgehensweise dieser Untersuchung sehr positiv und als
notwendig anzusehen, da die Messdaten auch immer gewissen Schwankungen
durch externe Einflüsse unterliegen.
Allgemein ist festzuhalten, dass Auslaufhaltungssysteme zwar eine gewisse
Anregung zur Bewegung bieten, aber mit maximal vier Stunden (insg. 62 – 248 Min.)
Bewegung pro Tag war der tägliche Anteil an Bewegung sehr viel geringer als
beispielsweise bei Pferden in freier Wildbahn oder ganzjähriger Weidehaltung. Somit
deckt ein Auslaufhaltungssystem trotz getrennter Funktionsbereiche und eines
großen Auslaufs nicht den Bewegungsbedarf der Pferde, wenn keine zusätzlichen
Bewegungsanreize und –möglichkeiten angeboten werden.
Eine zusätzliche Bewegung von Pferden ist nicht nur zur Gesunderhaltung des
Bewegungsapparates und der Körperfunktionen notwendig, sondern auch um das
Wohlbefinden und die Ausgeglichenheit der Pferde zu steigern.
[Horse husbandry systems with close-by discharge are considered to be a very livestock-
friendly housing form, as they offer a certain movement opportunity for the
animals. The aim of the present study was to examine how different movement and
space offerings affect the movement activities of horses in a group horse husbandry
with close-by discharge, and whether the discharge provides itself an adequate
incentive for movement. The impact that the form or rather intensity of movement has
on the wellbeing of the animals was also established.
Most of the horses held in Germany spend most of the day in the stable, although it is
meanwhile known that horses under natural housing conditions are 12 to 16 hours of
the day in motion. Therefore the improvement of stable housing systems applies a
special interest.
For this purpose, 24 warmblood mares, aged from 1½ to 3½ years, were studied in
single and group discharge husbandry systems from September 2004 until October
2005. Six horses formed an experimental group. In every group five variants of approximately
three weeks were proceeded. Thereby the group husbandry was supplemented
with three different additional movement opportunities (2 h pasture / day,
2 h non-grassy pasture land / day, 1 h free range horse walker / day). In the single
discharge husbandry (single box with 45 sq. m-large close-by discharge) and in one
experimental variant of the group husbandry got the horses, however, offered no additional
movement outside the husbandry system. The group husbandry system itself
was marked by the spatial division of the functional areas (lying, eating, drinking,
moving) and the close-by discharge measured 270 sq. m. In an additional phase of
the study, and expansion of the permanently accessible close-by discharge to
540 sq. m was found.
The movement activity was documented with pedometers attached respectively to
one hind leg of the horse and a supplementary analysis of video documentation. To
evaluate the stress exposure measurements of heart frequency variability (parameters
HF and SD2) and of the faecal cortisol metabolite concentration were performed.
Summary 195
The interpretation of the movement behaviour showed that additional two hours of
free movement on a pasture led to a significant increase in the average movement
activity (149.6 min / day), as well as one hour movement in a horsewalker did
(173.0 min / day). The non-grassy pasture land, however, didn’t inspire the horses of
the group husbandry to increased movement (131.6 min / day), but sometimes even
caused a decrease in movement activity. In the group discharge husbandry without
additional movement opportunities the movement activity was also low
(125.8 min / day), and during the single discharge husbandry without additional
movement the horses showed the least movement activity (102.3 min / day).
In analysing only the movement time in the stable system was no significant impact
of the additional movement outside the housing system to the rest of locomotion
ascertainable.
As well an expansion of the close-by stable discharge in the group husbandry system
had no increasing influence on the movement behaviour of the horses.
The stress exposure of the horses was least in the variations of group husbandry
with two hours on a pasture (SD2: 82.9 ms; cortisol metabolites: 29.0 nmol / kg faeces)
as well as one hour of movement in a free range horse walker (SD2: 99.2 ms;
cortisol metabolites: 27.7 nmol / kg faeces). The studies showed a rise in stress in
group husbandry with two hours of movement on a non-grassy pasture land without
feeding opportunity (SD2: 101.3 ms; cortisol metabolites: 39.6 nmol / kg faeces) as
well as in the variation of the group husbandry without additional movement offerings
(SD2: 113.3 ms; cortisol metabolites: 38.4 nmol / kg faeces). Judging from the mean
of the group the horses had a very high stress exposure in the variation of the single
husbandry without additional movement offerings (SD2: 123.8 ms; cortisol metabolites:
37.5 nmol / kg faeces). But a comparison of the group and single husbandry in
terms of the heart frequency variability showed that alltogether 70 % of the horses
experienced less stress if hold in a group. However, some horses (30 %) showed
reducing stress in the single husbandry, whereas here the influence of social hierarchy
seems to play a decisive role.
196 Summary
In consequence of the examination of several measuring parameters (both for stressand
for movement behaviour) parallel aligned tendencies become apparent in the
experimental variants, however, is a unique weighting of the parameters not possible.
Thus, the methodological approach of this study is to be regarde as very positive and
necessary, since the data always vary with some fluctuations by external influences.
In general it can be established that discharge husbandry systems offer some incentive
for the horse to move, but with a maximum of four hours (overall 62 – 248 min) of
movement per day, the daily proportion of movement was much less than, for example,
in the case of wild horses or year-round pasture keeping. Thus, if no additional
movement incentives and possibilities are offered, the discharge husbandry system
doesn’t cover the movement needs of the horse despite separate functional areas
and a large outside discharge.
Additional movement is not only necessary to keep the musculoskeletal system and
bodily functions of the horse healthy, but also to ensure the horse’s well being and
mental balance.]