|
|
Clutton-Brock, T. H., & Harvey, P. H. (1980). Primates, brains and ecology. J. Zool. Lond., 190(3), 309–323.
Abstract: The paper examines systematic relationships among primates between brain size (relative to body size) and differences in ecology and social system. Marked differences in relative brain size exist between families. These are correlated with inter-family differences in body size and home range size. Variation in comparative brain size within families is related to diet (folivores have comparatively smaller brains than frugivores), home range size and possibly also to breeding system. The adaptive significance of these relationships is discussed.
|
|
|
|
Schneider, G., & Krueger, K. (2012). Third-party interventions keep social partners from exchanging affiliative interactions with others. Anim. Behav., 83(2), 377–387.
Abstract: Third-party interventions are defined as the interruption of dyadic interactions by third animals through direct physical contact, interposing or threats. Previous studies focused on the analysis of interventions against agonistic encounters. However, there have been no evaluations of interventions against affiliative behaviours, particularly in relation to the intervening animal�s social relationships and its social and spatial position. Horses, Equus caballus, are an interesting model species, as interventions against affiliative interactions occur more frequently than against agonistic interactions. In this study, 64 feral horses displayed 67 interventions in affiliative interactions and eight interventions in agonistic interactions within the observation period. We analysed the interventions in affiliative encounters, and found that it was mainly higher-ranking females that intervened in the affiliative interactions of group mates in the stable horse harems. The intervening animals took an active part in affiliative and agonistic encounters within the group, but did not occupy particular social roles or spatial positions. They intervened in affiliative interactions in which group mates with which they had social bonds interacted with other members of the group. They targeted the nonbonded animal and approached the one with which they were socially bonded. We suggest some species use third-party interventions in affiliative interactions to prevent competition for preferred social interaction partners from escalating into more costly agonistic encounters.
|
|
|
|
Benz, B., Benitz, B., Krueger, K., & Winter, D. (2013). Weniger Einstreu bei gleichem Komfort. Pferdezucht und Haltung, 1, 66–71.
|
|
|
|
Hoffmann, G., Bockisch, F. - J., & Kreimeier, P. (2009). Einfluss des Haltungssystems auf die Bewegungsaktivität und Stressbelastung bei Pferden in Auslaufhaltungssystemen. Landbauforschung – vTI Agriculture and Forestry Research, 2(59), 105–112.
Abstract: Frühere Untersuchungen haben gezeigt, dass die tägliche Bewegung für die Gesunderhaltung der Pferde notwendig ist. Inwieweit sich jedoch unterschiedliche Bewegungsangebote auf das Stress-und Bewegungsverhalten von Pferden in einer Gruppen-Auslaufhaltung auswirken und ob der Bewegungsbedarf der Pferde durch eine Auslaufhaltung ohne zusätzliche Bewegung gedeckt werden kann, ist der Literatur bisher nicht zu entnehmen. Daher sollte in der nachfolgend beschriebenen Untersuchung der Frage nachgegangen werden, welche Auswirkungen verschiedene Bewegungsangebote auf die Bewegungsaktivität von Pferden in Gruppen-Auslaufhaltungen haben und ob diese das Wohlbefinden der Tiere beeinflussen. Letzteres wurde durch Messung der Herzfrequenzvariabilität und Bestimmung von Cortisolmetaboliten im Pferdekot erfasst und die Bewegungsaktivität der Pferde wurde mit ALT-Pedometern bestimmt.
Verglichen wurden eine Einzel-und Gruppenhaltung mit jeweils angrenzendem Auslauf, aber ohne eine zusätzliche Bewegung der Pferde außerhalb des Stalls. In drei weiteren Varianten der Gruppenhaltung bekamen die Pferde täglichen Auslauf auf einer unbegrünten Koppel, auf einer Weide oder durch gezielte Bewegung in einer Führanlage. Die Bewegungsaktivität konnte durch die zusätzliche Bewegung in Form von Weide oder Führanlage signifikant gesteigert werden.
Ein zusätzliches Bewegungsangebot führte bei den Pferden zu einer Abnahme der Stressbelastung und sollte auch den Pferden ermöglicht werden, die in einer Gruppenhaltung gehalten werden, um ihre physische und psychische Gesundheit zu erhalten.
[Former studies confirm the necessity of daily movement for the health of a horse. But so far no description could be found in the literature how different movement offerings impact the stress and movement behaviour of horses in group husbandries with close-by discharge. The same holds true for the question whether a discharge husbandry system can meet the movement requirements of horses if there isn�t any additional movement possibility. The aim of the present study was to examine different movement offerings, their effects on the movement activities of horses in a group horse husbandry with close-by discharge and the impact of the movement on the wellbeing of the animals.
The heart rate variability and the concentration of the cortisol metabolites in the horse excrement were analyzed for detecting the wellbeing of the horses. Additionally ALT-Pedometers were used for determining the movement activity.
A single and a group husbandry system, each with closeby discharge, were compared when horses had no additional movement outside the stable. In three further variants the group husbandry was supplemented with daily time on a non-grassy pasture land, a pasture or in a horse walker. Pasture or horse walker increased movement activity significantly. Nevertheless an additional movement offering resulted in a lower stress load of the horses and should also be allowed to horses in group husbandry systems to ensure the horse�s physical and mental health.]
|
|
|
|
Krueger., K., & Farmer, K. (2018). Social learning in Horses: Differs from individual learning only in the learning stimulus and not in the learning mechanisms. In 14th Meeting of the Internatinoal Society for Equitation Science.
Abstract: Equine welfare can be enhanced by applying species specific training. This may incorporate social learning, as horses are highly social and social stimuli are of primary importance. Social learning is comparable to individual learning in its learning mechanisms, differing primarily in the way it is stimulated. Our initial study showed that horses of different breeds (N = 38) follow humans after observing other horses doing so, but only if the observed horse was familiar to and higher ranking than the observer (Fisher's exact test: N = 12, P = 0.003). A second study showed that horses and ponies (N = 25) learned to pull a rope to open a feeding apparatus after observing demonstrations by conspecifics, again, only if the demonstrating horse was older and higher ranking than the observer (Fisher's combination test, N = 3, v2 = 27.71, p = 0.006). Our third approach showed that horses and ponies (N = 24) learned to press a switch to open a feeding apparatus after observing a familiar person (GzLM: N = 24, z = 2.33, P = 0.02). Most recently, we confronted horses and ponies (N = 50) with persons demonstrating different techniques for opening a feeding apparatus. In this study we investigated whether the horses would copy the demonstrators' techniques or apply their own. Here only some horses copied the technique, and most of the successful learners used their mouths irrespective of the demonstrators' postures (Chi Square Test: N = 40, df = 2, χ2 = 31.4, p < 0.001). In all the approaches social stimuli elicited learning processes in the test horses, while only a few individuals in the control groups mastered the tasks by individual learning. The following behaviour observed in the initial study may have been facilitated by a social stimuli (social facilitation), and the opening of the feed boxes in the subsequent studies appear to be mostly the result of enhancement (social enhancement). Some horses may have used the social stimuli at first and continued their learning process by individual trial and error. However, the horses were also selective in whom and some in how to copy. This may have been conditioned (socially conditioned) or the result of simple forms of reasoning on the reliability of the particular information provided by demonstrators of certain social ranks or social positions, as high ranking and familiar horses and familiar persons were copied and some imitated exactly.
Lay person message: Traditional riding instructions suggest that horses learn by observing other horses. For example, older, more experienced driving horses are used for initial training of young driving horses. We have shown that horses indeed use learning stimuli provided by other horse, as well as by humans. Horses readily accept stimuli observed in high ranking and familiar horses, and familiar persons. Such stimuli elicit learning processes which are comparable to individual learning. We suggest applying social learning whenever possible, as it is much faster and less stressful than individual learning, where learners experience negative outcomes in trial and error learning.
|
|
|
|
Bartal, I. B. - A., Decety, J., & Mason, P. (2011). Empathy and Pro-Social Behavior in Rats. Science, 334(6061), 1427–1430.
Abstract: Whereas human pro-social behavior is often driven by empathic concern for another, it is unclear whether nonprimate mammals experience a similar motivational state. To test for empathically motivated pro-social behavior in rodents, we placed a free rat in an arena with a cagemate trapped in a restrainer. After several sessions, the free rat learned to intentionally and quickly open the restrainer and free the cagemate. Rats did not open empty or object-containing restrainers. They freed cagemates even when social contact was prevented. When liberating a cagemate was pitted against chocolate contained within a second restrainer, rats opened both restrainers and typically shared the chocolate. Thus, rats behave pro-socially in response to a conspecific�s distress, providing strong evidence for biological roots of empathically motivated helping behavior.
|
|
|
|
Gibbs, P. G., & Cohen, N. D. (2001). Early management of race-bred weanlings and yearlings on farms. J. Equine Vet. Sci., 21(6), 279–283.
Abstract: A total of 58 Thoroughbred and Quarter Horse farms
that managed 1,987 weanlings and yearlings responded to
a survey designed to better characterize early management
of racing prospects. Average age at weaning was 5.5 months
and over half of all farms kept almost three-fourths of all
weanlings to be placed in pre-race training. Variation in
feeding practices was evident and while well over half
of all farms provided balanced nutrient supply to young
horses, 20% to 40% likely fed unbalanced diets. An obvious
preference existed for semi-confinement in young horses
with plenty of free exercise. The majority of farms reported
that young prospects were fed and managed for a moderate
rate of growth. Forced exercise occurred to a much larger
extent with yearlings than weanlings and 40% of farms
described the footing as soft, but not deep. Response to the
prevalence of developmental orthopedic diseases appeared
somewhat guarded, and average injury rate was low on
farms that attributed much of injury to horses playing too
hard. Technological advancements such as photoperiod
manipulation in broodmares were widely used, while
valuable tools such as body condition scoring were utilized
to a lesser extent.
|
|
|
|
Krueger, K. (2017). Perissodactyla Cognition. In J. Vonk, & T. Shackelford (Eds.), Encyclopedia of Animal Cognition and Behavior (pp. 1–10). Cham: Springer International Publishing.
|
|
|
|
Brinkmann, L., Gerken, M., Hambly, C., Speakman, J. R., & Riek, A. (2014). Saving energy during hard times: Energetic adaptations of Shetland pony mares. J. Exp. Biol., 217, 4320–4327.
Abstract: Recent results suggest that wild Northern herbivores reduce their metabolism during times of low ambient temperatures and food shortage in order to reduce their energetic needs. It is however not known if domesticated animals are also able to reduce their energy expenditure. We exposed ten Shetland pony mares to different environmental conditions (summer and winter) and to two food quantities (60 and 100% of maintenance energy requirement, respectively) during low winter temperatures to examine energetic and behavioural responses. In summer ponies showed a considerably higher field metabolic rate (FMR) (63.4±15.0 MJ d-1) compared to restrictively fed and control animals in winter (24.6±7.8 MJ d-1 and 15.0±1.1 MJ d-1, respectively). During summer conditions locomotor activity, resting heart rates and total water turnover were considerably elevated (P<0.001) compared to winter. Restrictively fed animals (N=5) compensated for the decreased energy supply by reducing their FMR by 26% compared to control animals (N=5). Furthermore, resting heart rate, body mass and body condition score were lower (29.2±2.7 beats min-1; 140±22 kg; 3.0±1.0 points) than in control animals (36.8±41 beats min-1; 165 ±31 kg; 4.4±0.7 points; P<0.05). While the observed behaviour did not change, nocturnal hypothermia was elevated. We conclude that ponies acclimatize to different climatic conditions by changing their metabolic rate, behaviour and some physiological parameters. When exposed to energy challenges, ponies, like wild herbivores, exhibited hypometabolism and nocturnal hypothermia.
|
|
|
|
Bentley-Condit, V., & Smith, E. O. (2010). Animal tool use: current definitions and an updated comprehensive catalog. Behaviour, 147(2), 185–32.
Abstract: Despite numerous attempts to define animal tool use over the past four decades, the definition remains elusive and the behaviour classification somewhat subjective. Here, we provide a brief review of the definitions of animal tool use and show how those definitions have been modified over time. While some aspects have remained constant (i.e., the distinction between 'true' and 'borderline' tool use), others have been added (i.e., the distinction between 'dynamic' and 'static' behaviours). We present an updated, comprehensive catalog of documented animal tool use that indicates whether the behaviours observed included any 'true' tool use, whether the observations were limited to captive animals, whether tool manufacture has been observed, and whether the observed tool use was limited to only one individual and, thus, 'anecdotal' (i.e., N = 1). Such a catalog has not been attempted since Beck (1980). In addition to being a useful reference for behaviourists, this catalog demonstrates broad tool use and manufacture trends that may be of interest to phylogenists, evolutionary ecologists, and cognitive evolutionists. Tool use and tool manufacture are shown to be widespread across three phyla and seven classes of the animal kingdom. Moreover, there is complete overlap between the Aves and Mammalia orders in terms of the tool use categories (e.g., food extraction, food capture, agonism) arguing against any special abilities of mammals. The majority of tool users, almost 85% of the entries, use tools in only one of the tool use categories. Only members of the Passeriformes and Primates orders have been observed to use tools in four or more of the ten categories. Thus, observed tool use by some members of these two orders (e.g., Corvus, Papio) is qualitatively different from that of all other animal taxa. Finally, although there are similarities between Aves and Mammalia, and Primates and Passeriformes, primate tool use is qualitatively different. Approximately 35% of the entries for this order demonstrate a breadth of tool use (i.e., three or more categories by any one species) compared to other mammals (0%), Aves (2.4%), and the Passeriformes (3.1%). This greater breadth in tool use by some organisms may involve phylogenetic or cognitive differences � or may simply reflect differences in length and intensity of observations. The impact that tool usage may have had on groups' respective ecological niches and, through niche-construction, on their respective evolutionary trajectories remains a subject for future study.
|
|
