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Wulf, M., Dörstelmann, V., & Aurich, C. (2008). Behavioural patterns of pony foals after simultaneous and consecutive weaning. In IESM 2008.
Abstract: In this study, the behaviour of Shetland pony foals after weaning was analysed. Foals were either weaned simultaneously (group SW; n=7) by removing all mares at the same time and leaving the foals as a group or foals were weaned consecutively (group CW; n=4) by removing one mare per day on consecutive days. Behaviour of the foals was observed 3 times per day (6:00-8:00, 12:00-14:00 and 18:00-20:00) from one day before weaning to 7 days (group SW) or 10 days (group CW) after removing the first mare. Vocalisation after removal mares was more frequent in foals weaned simultaneously (d 1: SW 66±37 per 2 hrs) than when mares were removed consecutively at one-day intervals (d1, i.e. removal of first mare: CW 3±2 per 2 hrs). In CW foals, vocalisation was most frequent on the day after removal of the last mare (day 5: 18±6 per 2 hrs), although it was lower than in SW foals on day 1 after weaning. Locomotor activity was highest in SW foals on days 1 and 2 after weaning (maximum 17±6 movements per 2 hrs, p<0.05 vs. CW: <2 movements per 2 hrs at all times). Frequency of defaecation increased to 7±1 per 2 hrs on day 1 after SW (p<0.05 vs. group CW), it was 3±2 per 2 hrs in group CW at the time 3 mares had been removed and was below 2 at all other times in both groups. The time, foals spent in lateral recumbency and in sternal recumbency was reduced to near zero during the two days following weaning (group SW) and the period during which mares were removed consecutively (group CW). Tactile contact between foals was increased in SW foals after weaning compared to CW foals during the period of consecutive weaning. Suckling on other foals increased in both groups for several days after weaning but did not differ between groups. No major changes over time or differences between groups were found for other behaviour parameters. Foals weaned simultaneously lost weight slightly but significantly (p<0.05) within two days after weaning (from 78±11 to 75±10) while no weight loss occurred in CW foals. In conclusion, SW elicited more pronounced behavioural changes than CW in pony foals. Consecutive weaning can be considered a more gentle method than SW and thus may be associated with lower risks and less stress for the foals.
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Jørgensen, G. H. M., Borsheim, L., Mejdell, C. M., & Bøe, K. E. (2008). Social interactions and spacing in horses (Equus caballus) grouped according to gender. In IESM 2008.
Abstract: The aim of this study was to investigate the social behaviour and spacing between horses when grouped according to gender in homogeneous- or heterogeneous groups, and to see if the amount and severity of aggression differed in relation to gender composition.
A total of 66 horses divided in six batches were used. In each batch, horses were allotted into one mare group, one gelding group and one mixed gender group, with most groups consisting of three or four animals. Three batches were performed on Icelandic horses and three batches on riding horses and -ponies. After 4-6 weeks of acclimatisation, a trained observer recorded all social interactions using direct, continuous observation one hour in the morning and one hour in the afternoon for three consecutive days. In addition, the nearest neighbour of each horse was recorded using instantaneous sampling every 10 minutes. The horses were inspected for injuries before grouping, day one after grouping and after 4-6 weeks. Furthermore, a novel object test and a handling test (taking horse out of group) were conducted after the behavioural observations were completed. No significant effect of gender composition was found on social interactions, spacing or injuries. Most of the aggressive interactions recorded were threats, and not aggressive interactions involving physical contact. Aggression seemed to increase with decreased space per animal and more horses per feeding place. Very few injuries were found and most were superficial. Horses showed a low degree of fearfulness in the novel object test and most horses were easy to handle in the “horse out of group test”. In conclusion, gender composition does not seem to have any effect on aggression level, spacing or injuries in social groups of horses. |
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Kaczensky, P., Ganbaatar, O., von Wehrden, H., & Walzer, C. (2008). Przewalski`s horses (Equus ferus przewalskii) and Asiatic wild asses (Equus hemionus): Similar Species, Same Habitat – Same Use? In IESM 2008.
Abstract: Historic overlap zones of wild equids were small in Africa but extensive for Przewalski`s horses and Asiatic wild asses in Asia. Currently the Great Gobi B Strictly Protected Area in SW Mongolia is the only place where sympatric, free-ranging populations of these equids occur. This provides an unique opportunity to examine the co-existence of these little studied species and test the hypothesis that Przewalski`s horses are primarily adapted to mesic steppe habitats, whereas Asiatic wild asses are adapted to arid desert steppes and semi-deserts.
We monitored 9 Przewalski`s horses and 7 wild asses with satellite telemetry and superimposed the data on a habitat map derived from remote sensing (LANDSAT TM & ETM+-data) and ground sample plots. We tested for habitat preferences comparing use and availability with a logistic regression mixed model approach. Individuals were treated as random factors. Factor variables were tested for significant differences in subsequent Tukey post-hoc tests. Przewalski`s horses had non-exclusive home ranges of 152-826 km² and heavily selected for the most productive riparian plant communities. Asiatic wild asses also had non-exclusive home ranges, but with 4,449-6,835 km² they were 10 times larger than those of Przewalski`s horses. Asiatic wild asses seem to use plant communities more or less relative to their availability. Our results provide evidence for two parallel resource selection strategies. Our findings indicate that the Gobi areas provide an edge, rather than an optimal habitat for Przewalski`s horses. This leaves only small and isolated pockets of suitable habitat for future re-introductions. Asiatic wild asses, on the other hand, need access to large tracts of land to cope with the unpredictable resource distribution of the Gobi. Thus, Asiatic wild ass conservation requires a large scale approach. |
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Wöhr, A. C., & Erhard, M. (2008). Polysonographic studies, about sleeping behaviour of horses. In IESM 2008.
Abstract: Objective: In the context of the ongoing discussion about keeping horses in individual stable boxes vs. in herds the lack of relaxation of the horse as a flight animal is an argument often put forward against individual housing. The long-term objective of our investigations is to determine the sleep phases in various housing systems in order to find a substantiated answer to that issue. For that purpose, the sleep waves measured by EEG have to be defined beforehand and allocated to the individual stages of sleep. The experiments described here are intended to support this effort. The objective is to establish a method which by means of a portable polysomnograph allows to capture the sleeping behaviour of horses for the purpose of defining the individual stages of sleep. It was investigated which stages of sleep horses undergo, and to what extent they may be comparable to those of humans.
Animals/materials/methods: Given the high technical effort involved, somnographic examination of large animals has so far been difficult and mostly required the animals to be sedated. Meanwhile, however, instruments such as the Somnoscreen by Somnomedics have become available. This is a completely portable polysomnograph with up to 28 channels and wireless online signal transmission and synchronous video transmission to a PC. Using this instrument, the sleep profile of 5 Icelandic ponies and 10 horses (different race) aged 5-10 years was recorded and evaluated for 4 or 5 nights per horse. The following parameters were assessed: EEG (electroencephalogram), EOG (electrooculogram), EMG (electromyogram), ECG (electrocardiogram), thoracic and abdominal breathing motions as well as identification of the body posture. Synchronous video recordings were made. EEG recordings were obtained through gold-coated disk electrodes with long flexible cables, applied and secured to the scalp. Results: As with humans, various stages of sleep can also be defined for horses using the above methods of recording. The waking condition is characterised by alpha waves, which just like in humans are within a range of 8-12 Hz. Typical REM phases as in humans were also detected, although not only when stretched completely on their side, as has hitherto always been described, but also when lying on their chest. Phases of deep sleep (stage 4) can also be measured, with the animals mostly in a standing position. The multi-stage human sleeping pattern, which is made up of 4-6 repeat phases of sleep (waking stage eyes open – waking stage eyes closed – REM phase – stage 1 – stage 2 – stage 3 – stage 4 – return to REM phase etc.) was found to be similar in horses in individual sequences. However, the sleep phases are shorter and more frequently interrupted by waking phases. Conclusions: Horses are flight animals, which is why they have to be “on eye” in every situation so as to be able to flee in the face of danger. In a natural herd lying positions are only assumed if one or more members watch over the herd. In some publications the REM phase is treated as equivalent to the deep sleep phase. Although the REM phase is a phase of total muscle relaxation it is at the same time the dream phase and due to the high frequencies and the low amplitudes in the EOG resembles Stage I. This means that the sleeping horse can be awakened very quickly from this REM phase so as to be able to react to any dangerous situation. It therefore makes sense for the horses to assume a lying position during REM phases as the muscles are relaxed, yet a waking condition can be reached very quickly. A standing position seems to be preferred during deep sleep phases, where waking takes rather long, so that at least the position will not have to be changed. Whether the sleeping behaviour changes depending on age and race has yet to be investigated. |
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Schmidt, A., Möstl, E., Neuhauser, S., Aurich, J., Müller, J., & Aurich, C. (2008). Changes in heart rate and cortisol release during initial training of three-year-old warmblood sport horse stallions. In IESM 2008.
Abstract: The first weeks of training in young sport horses have been suggested to represent a stressful period and training practises for horses have been questioned recently. So far, only limited data on the stress response of young horses to the initial training are available. Heart rate (HR) provides information on fitness of the horse but is also an indicator of stress or pain. Determination of cortisol metabolites in faeces is a non-invasive technique to determine a prolonged stress response. In our study, three-year-old warmblood sport horse stallions (n=8) were followed through a standardised 10-week classical training programme from lunging to first mounting of a rider and progressing to moderate work. Feed, housing and management were similar for all horses. HR was recorded with a mobile recording System (f810i, Polar, Kempele, Finland) fixed to a girth around the thorax of the horse and was monitored twice weekly from 30 min before to 30 min after training, i.e. including the training period. In addition, cortisol concentrations were determined in faecal samples collected three times daily. Overall basal HR before daily training was 39±2 (SEM) beats/min and mean values did not change significantly over the 10-week study period. Average HR during initial lunging (week 1) was 119±14 beats min and decreased to 95±5 beats/min in week 2. Due to individual variations this decrease did not reach statistical significance. Neither first mounting of a rider (89±10 beats/min) nor an increasing workload (e.g. week 8: 111±4 beats/min) were associated with prolonged increases in mean HR, but transient increases were recorded and the response to mounting of the rider differed markedly between stallions. After daily training, HR decreased rapidly but was slightly, although significantly (p<0.05, Friedman-test) higher than pre-work values (46±2 beats/min). Cortisol metabolite concentrations in faeces tended to decrease during the period of lunging, were not increased when the horses were first mounted by a rider but rose slightly with an increasing work load during the last 4 weeks of the 10-week training period. In conclusion, based on HR and faecal cortisol metabolite concentrations, the initial training of sport horse stallions in the classical German training system is not associated with major stress for the horse. The increase in HR during training is due to physical exercise itself and not associated with specific situations of the training programme.
Supported by a fellowship from Stiftung Forschung für das Pferd to AS |
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Scheiber, I. B. R., WeiB, B. M., Hirschenhauser, K., Wascher, C. A. F., Nedelcu, J. T., & Kotrschal, K. (2008). Does 'Relationship Intelligence' Make Big Brains in Birds? Open Biol J, 1, 6–8 (3).
Abstract: Lately, Emery et al. developed a bird-specific modification of the *social brain hypothesis*, termed *relationship intelligence hypothesis*. Although the idea may be valuable, we doubt that it is supported by sufficient evidence and critically discuss some of the arguments raised by the authors in favour of their new idea.
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Bigiani, A., Mucignat-Caretta, C., Montani, G., & Tirindelli, R. (2005). Pheromone reception in mammals. Reviews of Physiology, Biochemistry and Pharmacology, 154, 1–35.
Abstract: Pheromonal communication is the most convenient way to transfer information regarding gender and social status in animals of the same species with the holistic goal of sustaining reproduction. This type of information exchange is based on pheromones, molecules often chemically unrelated, that are contained in body fluids like urine, sweat, specialized exocrine glands, and mucous secretions of genitals. So profound is the relevance of pheromones over the evolutionary process that a specific peripheral organ devoted to their recognition, namely the vomeronasal organ of Jacobson, and a related central pathway arose in most vertebrate species. Although the vomeronasal system is well developed in reptiles and amphibians, most mammals strongly rely on pheromonal communication. Humans use pheromones too; evidence on the existence of a specialized organ for their detection, however, is very elusive indeed. In the present review, we will focus our attention on the behavioral, physiological, and molecular aspects of pheromone detection in mammals. We will discuss the responses to pheromonal stimulation in different animal species, emphasizing the complicacy of this type of communication. In the light of the most recent results, we will also discuss the complex organization of the transduction molecules that underlie pheromone detection and signal transmission from vomeronasal neurons to the higher centers of the brain. Communication is a primary feature of living organisms, allowing the coordination of different behavioral paradigms among individuals. Communication has evolved through a variety of different strategies, and each species refined its own preferred communication medium. From a phylogenetic point of view, the most widespread and ancient way of communication is through chemical signals named pheromones: it occurs in all taxa, from prokaryotes to eukaryotes. The release of specific pheromones into the environment is a sensitive and definite way to send messages to other members of the same species. Therefore, the action of an organism can alter the behavior of another organism, thereby increasing the fitness of either or both. Albeit slow in transmission and not easily modulated, pheromones can travel around objects in the dark and over long distances. In addition, they are emitted when necessary and their biosynthesis is usually economic. In essence, they represent the most efficient tool to refine the pattern of social behaviors and reproductive strategies. © Springer-Verlag 2005.
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Berge, J., Cottier, F., Last, K. S., Varpe, O., Leu, E., Soreide, J., et al. (2008). Diel vertical migration of Arctic zooplankton during the polar night. Biol Lett, .
Abstract: High-latitude environments show extreme seasonal variation in physical and biological variables. The classic paradigm of Arctic marine ecosystems holds that most biological processes slow down or cease during the polar night. One key process that is generally assumed to cease during winter is diel vertical migration (DVM) of zooplankton. DVM constitutes the largest synchronized movement of biomass on the planet, and is of paramount importance for marine ecosystem function and carbon cycling. Here we present acoustic data that demonstrate a synchronized DVM behaviour of zooplankton that continues throughout the Arctic winter, in both open and ice-covered waters. We argue that even during the polar night, DVM is regulated by diel variations in solar and lunar illumination, which are at intensities far below the threshold of human perception. We also demonstrate that winter DVM is stronger in open waters compared with ice-covered waters. This suggests that the biologically mediated vertical flux of carbon will increase if there is a continued retreat of the Arctic winter sea ice cover.
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Slater, P., Rosenblatt, J., Snowdon, C., & Roper, T. (2001). ADVANCES IN THE STUDY OF BEHAVIOR, 31 (Vol. 31). ACADEMIC PRESS.
Abstract: Description
The aim of Advances in the Study of Behavior remains as it has been since the series began: to serve the increasing number of scientists who are engaged in the study of animal behavior by presenting their theoretical ideas and research to their colleagues and to those in neighboring fields. We hope that the series will continue its “contribution to the development of the field”, as its intended role was phrased in the Preface to the first volume in 1965. Since that time, traditional areas of animal behavior have achieved new vigor by the links they have formed with related fields and by the closer relationship that now exists between those studying animal and human subjects. Advances in the Study of Behavior, Volume 31 continues to serve scientists across a wide spectrum of disciplines. Focusing on new theories and research developments with respect to behavioral ecology, evolutionary biology, and comparative psychology, these volumes foster cooperation and communications in these dense fields. Audience Experimental psychologists studying animal behavior, comparative psychologists, ethologists, evolutionary biologists, and ichthyologists. Contents Contributors. Preface.M.L. East and H. Hofer, Conflict and Co-operation in a Female Dominated Society: A Re-assessment of the “Hyper-aggressive” Image of Spotted Hyenas.C. ten Cate, H. Slabbekoorn, and M.R. Ballintijn, Bird Song and Male-male Competition: Causes and Consequences of Vocal Variability in the Collared Dove (Streptopelia Decaocto).R.W. Byrne, Imitation of Novel Complex Actions: What Does the Evidence from Animals Mean?L.J. Rogers, Lateralization in Vertebrates: Its Early Evolution, General Pattern and Development.S.H. Hulse, Auditory Scene Analysis in Animal Communication.P.K. Stoddard, Electric Signals: Predation, Sex, and Environmental Constraints.T. Aubin and P. Jouventin, How to Vocally Identify Kin in a Crowd: The Penguin Model. Index. Contents of Previous Volumes. |
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Basile, M., Boivin, S., Boutin, A., Blois-Heulin, C., Hausberger, M., & Lemasson, A. (2009). Socially dependent auditory laterality in domestic horses (Equus caballus). Anim. Cogn., 12, 611–619.
Abstract: Laterality is now known to be an ubiquitous phenomenon among the vertebrates. Particularly, laterality of auditory processing has been demonstrated in a variety of species, especially songbirds and primates. Such a hemispheric specialization has been shown to depend on factors such as sound structure, species specificity and types of stimuli. Much less is known on the possible influence of social familiarity although a few studies suggest such an influence. Here we tested the influence of the degree of familiarity on the laterality of the auditory response in the domestic horse. This species is known for its social system and shows visible reactions to sounds, with one or two ears moving towards a sound source. By comparing such responses to the playback of different conspecific whinnies (group member, neighbor and stranger), we could demonstrate a clear left hemisphere (LH) preference for familiar neighbor calls while no preference was found for group member and stranger calls. Yet, we found an opposite pattern of ear side preference for neighbor versus stranger calls. These results are, to our knowledge, the first to demonstrate auditory laterality in an ungulate species. They open further lines of thought on the influence of the social “value” of calls and the listener's arousal on auditory processing and laterality.
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