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Austin, N. P., & Rogers, L. J. (2012). Limb preferences and lateralization of aggression, reactivity and vigilance in feral horses, Equus caballus. Anim. Behav., 83(1), 239–247.
Abstract: Observational field studies were conducted on two remote populations of feral horses in Australia to determine whether lateralization is a characteristic of Equus caballus as a species or results from handling by humans. Group 1 had been feral for two to five generations and Group 2 for 10–20 generations. In both groups, left-side biases were present during agonistic interactions and in reactivity and vigilance. Therefore, as in other vertebrates, the right hemisphere appears to be specialized to control agonistic behaviour and responses to potential threats. The leftwards bias was stronger in measures of behaviour involving more aggression and reactivity. Preferences to place one forelimb in front of the other during grazing were also determined. No population bias of forelimb preference was found, suggesting that such limb preferences present in domestic horses may be entrained. Since stronger individual limb preferences were found in immature than in adult feral horses, limb preference may be modified by maturation or experience in the natural habitat. Stronger limb preference was associated significantly with elevated attention to the environment but only in younger feral horses. No sex differences in lateralization were found. The findings are evidence that horses show visual lateralization, as in other vertebrates, not dependent on handling by humans. Limb preference during grazing, by contrast, does appear to depend on experience.
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Obergfell, J. (2012). Einf lus s v on St ruktur e l ement en auf da s Li eg ev e rha l t en v on Pf e rden in Gruppenha l tung unt e r Be rücks i cht igung de s Ag g r e s s i ons v e rha l t ens. Ph.D. thesis, , Karlsruhe.
Abstract: Durch die vorliegende Studie wurde der Einfluss von Strukturelementen auf das Liege- und Aggressionsverhalten von Pferden in Gruppenhaltung untersucht. Die Strukturelemente sollten Rückzugsmöglichkeiten bieten, sowie in ihrem Bereich zur Aufhebung der Individualdistanz führen und dadurch die Fläche relativ vergrößern. Für die Versuche stellte das Haupt- und Landesgestüt Marbach drei unabhängige Pferdegruppen mit verschiedener Herdengröße zur Verfügung, die jeweils in Einraum- Innenlaufställen gehalten wurden. Die Datenerfassung fand zwischen 23 und sieben Uhr statt. Insgesamt wurden 366 Stunden Videomaterial ausgewertet. Beim Ruheverhalten wurden mit Hilfe des event-sampling- Verfahrens die Parameter Gesamtliegedauer, Dauer in Seitenlage, Dauer der Einzelphasen in
Seitenlage und Abliegehäufigkeit pro Nacht erfasst. Es wurden Versuchsphasen ohne
Strukturelemente und mit hängenden Planen als Strukturierung durchgeführt. Im ersten Stall
kamen außerdem über einander gestapelte Strohballen zum Einsatz. Diese Art der
Strukturierung stellte sich jedoch als nicht praktikabel heraus und führte im Vergleich zu den Planen zu einer signifikanten Verschlechterung der Gesamtliegedauer. In Stall 1 konnte man eine tendenzielle Verbesserung der Parameter Gesamtliegedauer und Gesamtdauer in Seitenlage durch das Anbringen von Planen sehen. In Stall 3 dagegen verschlechterte sich das Ruheverhalten in den Versuchsphasen mit Planen gegenüber den Versuchsphasen ohne Struktur. Die Werte der Gesamtdauer in Seitenlage nahmen signifikant ab. In Stall 2 zeigten sich keine Unterschiede in den verschiedenen Versuchsphasen. Möglicherweise ist die Wirkung der Strukturelemente auf das Liegeverhalten abhängig von der Flächengröße. Stall 1 hatte bezogen auf die Leitlinien des BMELV die größte und Stall 3 die kleinste Fläche. Bei den anderen Parametern des Liegeverhaltens gab es keine signifikanten Unterschiede in den verschiedenen Versuchsphasen. Mit Hilfe des time-sampling-Verfahrens wurde die Anzahl gleichzeitig liegender Pferde und gleichzeitig liegender Pferde in Seitenlage bestimmt. Auch hier zeigten sich keine Unterschiede in den verschiedenen Versuchsphasen. Bei der Gegenüberstellung der Werte der Gesamtliegedauer und der Gesamtdauer in Seitenlage mit dem Alter der Pferde (Stall 1 und Stall 3) und mit dem Integrationszeitpunkt (Stall 1) konnte kein Zusammenhang festgestellt werden. Beim Aggressionsverhalten wurden mit Hilfe des
event-sampling-Verfahrens in den Ställen 2 und 3 verschiedene Arten von Aggressionen
erfasst, die dann in die drei Intensitätsgrade Low-Level-, Mid-Level- und High-Level-
Aggressionen unterteilt wurden. Neben der Anzahl wurde die Dauer der verschiedenen
Aggressionen bewertet. Insgesamt konnte eine positive Wirkung der Planen auf das
Aggressionsverhalten beobachtet werden. Die Gesamtanzahl an Aggressionen nahm in beiden
Ställen tendenziell in den Versuchsphasen mit Planen ab. In Stall 3 konnte, wenn man die
Aggressionen stundenweise betrachtet, ein signifikanter Unterschied festgestellt werden.
Auch der Hinterhandschlag und die Aggressionen, welche das Ruheverhalten stören,
verringerten sich tendenziell nach dem Anbringen von Strukturelementen. In beiden Ställen
nahm die relative Häufigkeit von Mid-Level-Aggressionen nach dem Anbringen von Planen
zu. Dagegen konnte bei den High-Level-Aggressionen und in Stall 3 bei den Low-Level-
Aggressionen eine relative Abnahme beobachtet werden. Sowohl die Anzahl als auch die
Dauer der Mid-Level-Aggressionen verringerten sich in Stall 3 stundenweise betrachtet
signifikant in den Versuchsphasen mit Planen. In Stall 2 war bei den High-Level-
Aggressionen sowohl bei der Dauer als auch bei der Anzahl eine signifikante Abnahme zu
sehen. Wenn man das Aggressionsverhalten in Bezug zu der Fläche in den zwei Ställen
betrachtet, schien diese vor allem einen Einfluss auf die High-Level-Aggressionen zu
nehmen. Mit Hilfe des Rangindex der Pferde im Stall 3 wurde eine Rangordnung aufgestellt.
Zwischen dem Platz der Pferde in der Rangordnung und den Parametern des Ruheverhaltens
(Gesamtliegedauer, Gesamtdauer in Seitenlage) sowie dem Alter der Pferde konnte kein
Zusammenhang festgestellt werden. Zwischen dem Rangindex und der Gesamtanzahl an
Aggressionen bestand dagegen ein hoch signifikanter Zusammenhang. Im Rahmen dieser
Studie ist das Anbringen von Strukturelementen in Bezug auf das Aggressionsverhalten in
Einraum-Innenlaufställen von Pferden zu empfehlen. Die Wirkung auf das Liegeverhalten der
Pferde sollte in weiteren Studien untersucht werden.
[In this study the influence of structural elements on lying and aggression behavior in horses
kept in groups was exanimated. Structural elements should offer the possibility of retreat.
Furthermore, within the respective area, the individual distance should be limited, thus
increasing the overall space relatively. For the studies the “Haupt- und Landesgestüt
Marbach” provided three non-related groups of different sized horses, each kept in separate
“Einraum-Innenlaufställen”. Data collection took place between 11 pm and 7 am. Altogether,
366 hours of video material were analyzed. Using the event-sampling-method, the following
parameters within the horses´ resting behavior were determined: The total lying period, the
total lying period in lateral position, the periods of the single lying in lateral position and the
frequency of lying down. Test phases were carried out without structural elements and with
hanging canvases as structural elements. In the first stable there were also three bales of straw
piled up on top of each other. This kind of structuring emerged as impractical and in
comparison to the canvas, led to a significant deterioration to the total period of lying. After
the canvases were fixed in the first stable, a slight improvement with the parameters of total
lying period and total lying period in the lateral position could be seen. In contrast, the resting
behavior in stable 3 worsened in the test phases with the canvases in comparison to the test phases without structural elements. The values for the total lying period in the lateral position
decreased significantly. In stable 2, there were no differences in the different test phases.
Possibly the effect of the structural elements is dependent of the space. Stable 1 had the
largest space and stable 3 the least space referred to the guideline of the BMELV. The other
parameters of the lying behavior showed no significant differences in the different test phases.
The number of horses lying at the same time, and the number of horses lying at the same time
in the lateral position were detected with the aid of the time-sampling-method. There were
also no differences between the different test phases. If the values of the total lying period and
the total lying period in lateral position were compared to the age of the horses (stable 1 and
stable 3) and to the point of integration (stable 1), there was no correlation.
Different kinds of aggression were detected by the means of the event-sampling-method in
stable 2 and 3 and were subdivided into the three levels of intensity: Low-level-, mid-level
and high-level-aggressions. Both the number and the duration of the different aggressions
were evaluated. All in all a positive influence of the canvas on the aggression behavior could
be observed. In both stables, the total number of aggressions decreased in the test phases with
canvases. In stable 3 a significant difference could be detected, if the aggressions were
observed per hour. Also hind limb kicks and aggressions disturbing the resting behavior,
decreased by trend, after fixing the canvases in the stable. In both stables the relative
frequency of mid-level-aggressions increased after the canvases were mounted. In contrast
there was a relative decrease at the high-level-aggressions and in stable 3 at the low-levelaggressions.
The number and the duration of the mid-level-aggressions in stable 3 decreased,
when considered by the hour in the test phases with canvases. In stable 2 a significant
decrease in duration and number of high-level-aggressions was observed. When examining
aggression behavior in reference to space in the two stables, high-level-aggressions seemed to
be mostly influenced. In stable 3 a rank order was established with the aid of the rank index of
the horses. There was no correlation between the horses´ rank and the parameters of the
resting behavior (the total lying period, the total lying period in lateral position) and between
horses´ rank and age. In contrast, there was a high significant correlation between the rank
index and the total number of aggressions. In context to this study, structural elements in
“Einraum-Innenlaufställen” (BMELV 2009) seem to have a positive influence on the
aggression behavior and thus seem to be recommendable. The influence on the lying behavior
should be investigated in further studies.]
Keywords: Pferde, Ruheverhalten, Liegeverhalten, Aggressionsverhalten, Strukturelemente, Rangordnung [horses, rest behavior, lying behavior, aggression behavior, structural elements, rank order]
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Ahrendt, L. P., Christensen, J. W., & Ladewig, J. (2012). The ability of horses to learn an instrumental task through social observation. In Applied Animal Behaviour Science (Vol. 139, pp. 105–113).
Abstract: The ability of horses to learn through social observation may ease the implementation of new management systems, because the use of automatic feeders etc. by naive horses could be facilitated by observation of experienced horses. However, previous studies found no documentation for observational learning abilities in horses. This study aimed to investigate the ability of horses to learn an instrumental task from a familiar conspecific when social interaction was allowed during the demonstration. Two similar experiments were performed. In the first experiment, Observer horses (n=11) participated in ten successive demonstrations, where a trained Demonstrator opened an operant device by pushing a sliding lid aside with the muzzle in order to obtain a food reward. Immediately after the demonstrations the Observer horses were given the opportunity to operate the device alone. Control horses (n=11) were aware that the device contained food but were presented to the operant device without demonstration of the task. The learning criterion was at least two openings. Accomplishment of and latency to accomplish the learning criterion, and investigative behaviour towards the operant device were recorded. Five Observers and one Control, out of the eleven horses in each treatment group, accomplished the learning criterion. Even though this presents a high odds ratio (OR) in favour of the Observer treatment (OR=7.6), there was no significant difference between the treatment groups (P=0.15). Analysis of investigative behaviour showed, however, that the demonstrations increased the motivation of the Observer horses to investigate the device. Subsequently, a similar experiment was performed in a practical setting with 44 test horses (mixed age, gender and breed). We used the same operant device and the same number and type of demonstrations, although the horses were held on a loose rope to minimise aggression. In this second experiment, six of 23 Observer horses and five of 21 Control horses learned the instrumental task, representing no influence of the demonstration. Thus, this study did not demonstrate an ability of horses to learn an instrumental task through observation.
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Hartmann, E., Keeling, L. J., & Rundgren, M. (2011). Comparison of 3 methods for mixing unfamiliar horses (Equus caballus). J Vet Behav Clin Appl Res, 6(1), 39–49.
Abstract: Horses are likely to exhibit aggression when meeting for the first time. Therefore, this study compared 3 methods for mixing horses to evaluate their effectiveness in reducing aggressive interactions: (1) mixing pairs of horses in a paddock (P, 10 minutes, 15 tests), (2) introducing 1 unfamiliar horse to a pair of familiar, resident horses in a paddock (PP, 10 minutes, 15 tests), (3) allowing limited physical contact between pairs of horses for a short period of pre-exposure in neighboring boxes (B, 5 minutes, 16 tests) before mixing them in a paddock (BP, 10 minutes 16 tests). A total of 16 Swedish Standardbred mares, aged 6-18 years (mean age ± SD: 11 ± 4.4), were included in the study. Half of the horses were familiar with each other (resident horses, n = 8), whereas the other half were bought in from a variety of sources (unfamiliar horses, n = 8). Social interactions, consisting of behaviors from the sender, the receiver, and the subsequent sender's response, were recorded continuously as frequencies. There were no differences in the frequencies of aggressive behaviors between the 3 mixing methods, including those aggressive behaviors in which physical contact had been attempted (kick, strike). Although resident horses were overall more aggressive (median number of aggressive behaviors per horse, 62; Q1, 36; Q3, 68.5) than unfamiliar horses (median per horse, 4; Q1, 2; Q3, 12.5) during all tests (U = 97, P = 0.003), none of the 62 tests needed to be terminated. Unfamiliar horses did not receive more aggression from resident horses in PP (mean per test ± SD: 5.1 ± 3.1) than in P (mean per test ± SD: 6.4 ± 4.9) (t = 0.63, P = 0.544). However, the behavior “attack” was more frequent in PP (median per test, 2; Q1, 0; Q3, 5) than in P (median per test, 0; Q1, 0; Q3, 1) (U = 282, P = 0.042), and “flee” was more frequent in PP (median per test, 6; Q1, 4; Q3, 8) than in P (median per test, 1; Q1, 0; Q3, 6) (U = 290, P = 0.018). Pre-exposure in boxes did not reduce aggression in BP (median per test, 7; Q1, 4.3; Q3, 11.8) as compared with P (median per test, 6; Q1, 2; Q3, 16) (U = 264, P = 0.767), but during pre-exposure in B tests, horses exchanged more nonaggressive (median per test, 2; Q1, 0.3; Q3, 4) than aggressive (median frequency of aggressive behavior, 0; Q1, 0; Q3, 1) (W = 71, P = 0.013) and mixed interactions (median per test, 0; Q1, 0; Q3, 1) (W = 92, P = 0.016) through the opening. Results suggest mixing an unfamiliar horse with 2 resident horses at the same time instead of one by one may be preferable. In this way, the total aggression received by the unfamiliar horse will potentially be less, even though aggressive interactions may be more intense.
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Flauger, B. (2011). The introduction of horses into new social groups with special regard to their stress level. Ph.D. thesis, , .
Abstract: Horses are a highly social species living in complex social systems which should require them to memorise and generalise social experiences and distinguish between familiar and unfamiliar conspecifics. In the main part of my thesis I concentrated on the specific conflict situation of a horse being introduced into a new social group, and investigated its behaviour and stress level. Horses were either introduced (1) immediately, (2) after an observation period, or (3) together with an integration horse after an observation period. Additionally, in the second part of my thesis I arranged several experiments to elaborate additional aspects which could affect the behaviour of horses during introductions. In this study I could describe a simplified method for measuring stress through the analysis of faecal GCMs in horses. An enzyme immunoassay (EIA) for 11-oxoaetiocholanolone using 11-oxoaetiocholanolone-17-CMO: BSA (3?,11-oxo-A EIA) as antigen showed high amounts of immunoreactive substances. The new assay increases the accuracy of the test and lowers the expenses per sample; also storing of samples at room temperature after collection is less critical. This is a big advantage both in the field of wildlife management of equids and in the field of equestrian sports (chapter 1). Comparing the different introduction techniques, the introduction with an integration horse led to significantly less total interactions and lower levels of aggression than the introduction of single horses, both immediately and after several days of observing the new group. Additionally, by observing the behaviour of the horses during everyday sociality I could develop a formula describing the interrelationship between expected aggression level and enclosure size per horse. The curve takes an exponential shape. Starting from a space allowance of 300 m2 and more per horse, the amount of aggressions per hour approaches zero. For the reduction of aggression levels and injury risks in socially kept horses I recommend an enclosure size of at least 300 m2 per horse (chapter 2). I further investigated the stress level of the introduced animals. Horses which were immediately introduced did not show elevated faecal GCMs. In contrast, horses which were introduced after an observation period had slightly elevated values 2 and 3 days after the introduction. For horses introduced together with an integration horse faecal GCMs were significantly above the baseline value on the day of introduction and 1 day after it. These differences between introduction techniques indicate that the introduction event itself is not as stressful as previously assumed. Rather standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses (chapter 3). In the commentary of chapter 4 several studies are discussed which failed to demonstrate social learning in horses. It is argued that they did not consider important aspects which could have an influence, such as the dominance status or the social background of the horses (chapter 4). In chapter 5 a social feeding situation was investigated. The social rank as well as the position of conspecifics affected the feeding strategy of horses. Domestic horses used social cognition and strategic decision making in order to decide where to feed. When possible they tended to return to the same, continuously supplied feeding site and switched to an ?avoidance tendency? in the presence of dominant horses or when another horse was already feeding there (chapter 5). One possibility to recognize group members is through olfactory recognition. In chapter 6 it is shown that horses are able to distinguish their own from their conspecifics? faeces. In addition, they paid most attention to the faeces of those group members from which they received the highest amount of aggressive behaviour (chapter 6). Horses show cognitive abilities because they are able to use humans as local enhancement cues when searching for food, independently of their body posture or gaze consistency when the persons face them. Moreover, they seem to orientate on the attention of familiar persons more than of unfamiliar persons (chapter 7). Altogether, the results of this thesis provide further support for the view that horses show good conflict resolution strategies. They are perfectly able to deal with the conflict situation of being introduced to new group members, and the introduction event itself is not as stressful as previously assumed. It is rather suggested that standing together with an integration horse and not being able to integrate immediately into the complete group elicits stress in horses. All additional experimental set-ups could demonstrate that horses are well capable of social cognition.
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Cozzi, A., Sighieri, C., Gazzano, A., Nicol, C. J., & Baragli, P. (2010). Post-conflict friendly reunion in a permanent group of horses (Equus caballus). Behav. Process., 85(2), 185–190.
Abstract: Gregarious animals living in permanent social groups experience intra-group competition. Conflicts over resources can escalate into costly aggression and, in some conditions, non-dispersive forms of conflict resolution may be favoured. Post-conflict friendly reunions, hence reconciliation, have been described in a variety of species. The aim of this study was to explore, for the first time, the occurrence of reconciliation in a group of domestic horses (Equus caballus) and learn more about strategies used to maintain group cohesion. The behaviour of seven horses living as permanent group in an enclosure for at least 2 years was observed by video for 108 h from June to August 2007. We used a Post-Conflict/Matched Control method to assess the existence of reconciliation and third-party affiliation. Behaviours recorded Post-Conflict, or during Matched Control periods, were classified as affiliative based on previous descriptions of visual communication patterns in horses. The proportion of attracted pairs over total post-conflict situations was significantly greater than the proportion of dispersed pairs, both during dyadic interactions (p < 0.001) and during triadic interactions (p = 0.002). The results of the present study show that both dyadic reconciliation and third-party post-conflict affiliative interactions form important social mechanisms for managing post-conflict situations in horses.
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Hartmann, E. (2010). Managing horses in groups to improve horse welfare and human safety. Ph.D. thesis, , .
Abstract: Managing horses in groups to improve horse welfare and human safety
:
reactions to mixing and separation
Hartmann, Elke (2010) Managing horses in groups to improve horse welfare and human safety . Doctoral diss. Dept. of Animal Environment and Health, SLU. Acta Universitatis agriculturae Sueciae vol. 2010:87.
Full text available as:
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Abstract
The aim of this thesis was to investigate whether specific anecdotal concerns related to keeping horses in groups are supported by science and, if so, provide scientifically based recommendations that could be implemented in practice.
The aim of studies I and II was to identify methods for mixing unfamiliar horses that could minimise aggressive interactions and associated risk of injury. Results of study I revealed that pre-exposure of young horses in neighbouring boxes tended to lower contact-aggression (e.g. kicks, strikes) and biting behaviour in particular was reduced when the same pair of horses subsequently met in a paddock. This was not found when older horses were mixed (study II). Aggressive behaviour received by a new horse was not significantly different in meetings when it met one other horse compared to meeting two unfamiliar horses at the same time.
Removing a horse from a group of four in study III was generally unproblematic. Most horses approached the handler when she was catching the horse and while standing with it in the middle of the paddock. Thus, potential risk may be higher in situations when the handler remains relatively stationary, as other horses of the group have time to approach. Rank did not influence the number of horses following to the paddock gate and interactions between horses were rare.
Since horses naïve to social separation may be more difficult to handle away from the group, the objective in study IV was to investigate whether the initial presence of a companion horse would modify responses to separation. Results revealed no significant differences in heart rates and the number of training sessions required when the horses were subsequently trained in the absence of the partner compared to horses trained alone from the start.
In summary, results give little support for the original areas of concerns about mixing and separating horses. Risk of injury to both horses and humans should not be overestimated when handling horses in groups, but being aware of potential risk situations and being able to react accordingly is likely to increase horse welfare and human safety.
Faculty: Faculty of Veterinary Medicine and Animal Science
Keywords:
equine, behaviour, welfare, housing, mixing, aggression, injury, separation, habituation, learning
Agrovoc terms:
horses, behaviour, bites, injurious factors, animal learning, animal welfare, sweden
ISBN: 978-91-576-7532-3
Series.: Acta Universitatis agriculturae Sueciae
ISSN: 1652-6880
Volume: 2010:87
Papers/manuscripts:
I. Hartmann, E., Winther Christensen, J., Keeling, L.J. (2009). Social interactions of unfamiliar horses during paired encounters: Effect of pre-exposure on aggression level and so risk of injury. Applied Animal Behaviour Science 121, 214-221.
II. Hartmann, E., Rundgren, M., Keeling, L.J. (in press). Comparison of 3 methods for mixing unfamiliar horses (Equus caballus). Journal of Equine Veterinary Behavior: Clinical Applications and Research.
III. Hartmann, E., Søndergaard, E., Keeling, L.J. Identifying potential risk situations for humans when removing horses from groups. Manuscript.
IV. Hartmann, E., Christensen, J.W., Keeling, L.J. (in press). Training young horses to social separation: Effect of a companion horse on training efficiency. Equine Veterinary Journal.
Number of pages: 75
Year of publication: 2010
Language: eng
ID Code: 2396
Deposited By: Hartmann, Elke
Deposited On: 08 November 2010
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Hewitt, S. E., Macdonald, D. W., & Dugdale, H. L. (2009). Context-dependent linear dominance hierarchies in social groups of European badgers, Meles meles. Anim. Behav., 77(1), 161–169.
Abstract: A social hierarchy is generally assumed to exist in those mammalian societies in which the costs and benefits of group living are distributed unevenly among group members. We analysed infrared closed-circuit television footage, collected over 3 years in Wytham Woods, Oxfordshire, to test whether social groups of European badgers have dominance hierarchies. Analysis of directed aggression between dyads revealed linear dominance hierarchies in three social-group-years, but patterns within social groups were not consistent across years. Dominance hierarchies were significantly steeper than random in five out of six social-group-years. In those social-group-years where a linear hierarchy was determined, there was an effect of sex on dominance rank, with females gaining significantly higher rank than males in two social-group-years. Overall, rank was not related to age, nor did it appear to affect the likelihood of an individual being wounded, or an individual's breeding status. The latter resulted from nonorthogonality between sex and breeding status, as there were only two breeding males. Overall, hierarchies were primarily dominated by breeding females, and may occur when breeding competition arises. Relatedness, unreciprocated allogrooming and sequential allomarking were not consistently related to levels of directed aggression across social-group-years. We suggest that dominance structures within European badger groups may be context dependent, with future study required to complete our understanding of where, and when, they arise.
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Ostner, J., Heistermann, M., & Schülke, O. (2008). Dominance, aggression and physiological stress in wild male Assamese macaques (Macaca assamensis). Hormones and Behavior, 54(5), 613–619.
Abstract: In group-living animals relative rank positions are often associated with differences in glucocorticoid output. During phases of social stability, when dominance positions are clear and unchallenged, subordinates often face higher costs in terms of social stress than dominant individuals. In this study we test this prediction and examine additional potential correlates of stress, such as reproductive season, age and amount of aggression received in wild, seasonally breeding Assamese macaques (Macaca assamensis). During a mating and a non-mating season we collected 394 h of focal observational data and 440 fecal samples of six adult and six large subadult males living in a multimale-multifemale group in their natural habitat in northeastern Thailand. The mating season was characterized by a general increase in aggressive behavior and glucocorticoid excretion across all males compared to the non-mating season. Among adult males, mating season glucocorticoid levels were significantly negatively related with dominance rank and positively with the amount of aggression received. Both relationships were non-significant among large subadult males. Thus, our results suggest that in adult Assamese macaques a high dominance position is not associated with high costs. Low costs of dominance might be induced by strong social bonds among top-ranking males, which exchange frequent affiliative interactions and serve as allies in coalitionary aggression against potentially rank-challenging subordinate males.
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Feuerstein, N., & Terkel, J. (2008). Interrelationships of dogs (Canis familiaris) and cats (Felis catus L.) living under the same roof. Appl. Anim. Behav. Sci., 113(1-3), 150–165.
Abstract: In the process of domestication, dogs (Canis familiaris) and cats (Felis catus) have undergone thousands of years of genetic changes that have adapted them to the human environment. Both species have acquired a global distribution and it has become quite common to find homes with the two living side by side. Nevertheless, there is widespread belief that interspecific communication between dogs and cats is problematic, stemming from their separate evolutionary development and different social structures. Consequently, many people considering possible adoption of both species are concerned about their ability to get along. Interrelationships of dogs and cats living together were studied here in an attempt to determine the main factors influencing the type of relationship likely to develop between the two species. Two approaches were used: (1) a questionnaire completed by owners of both dog(s) and cat(s), which provided a broad database of the animals' behaviors; and (2) observations carried out in participants' homes on their dog-cat interactions. Two separate ethograms for dogs and cats served for analyses of their body language. The findings revealed the following: Both species showed a similar ability to establish a relatively amicable relationship with the other species; the animals' gender had little influence on the nature of their interrelationship; and adoption of the cat prior to the dog appears to conduce to establishing an amicable relationship, as does their first encounter taking place at an early age (up to 6 months of age in cats and up to 1 year in dogs). The findings also suggest that the majority of these dogs and cats understood the particular body language displayed by one animal that has an opposite meaning for the other species; and that the earlier the age of first encounter between the two, the better this understanding. It can be concluded that exposure of both species at an early age to the presence of the other facilitates the learning of each other's body language, and the consequent establishment of an amicable relationship. A better understanding of the various factors that contribute to determining the two species' relationship should not only improve the quality of life of these pets, but also reassure and encourage more people to adopt both cat and dog.
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