Estudios sobre animales

  • Effects of sounds of different quality on the behaviour and heart beat parameters of goats

    Authors: Johns, J., Patt, A., Hillmann, E. (2015)

    In alpine regions, bells are used to relocate free-ranging grazers like cows and goats. Considering that goats have a well-developed hearing capacity, sounds (e.g. a chime of a bell) mayact as stressors depending on their characteristics. The aim of this study was to test whethera non-uniform sound (chime of a bell) varying in amplitude and frequency and a uniform sound (sinusoidal tone) with continuously increasing amplitude and constant frequency lead to stress responses in terms of behaviour and heart beat. Twenty-nine goats were tested individually in a test arena in two sessions, each lasting five consecutive days with one trial per day. A day before the first trial, reference values were collected without playback. During the following five trials, playbacks were conducted. Differences in behaviour and heart beat parameters between test and reference values were analysed by using generalised linear mixed-effects models. During the first trial, the relative feeding duration was decreased and the relative alertness duration was increased during both stimuli, but more when goats were exposed to the non-uniform than the uniform sound. For both stimuli, the relative feeding duration increased (trial × stimulus: P = 0.05) and the relative alertness duration decreased (trial × stimulus: P = 0.004) from the first to the fifth trial but returned to the levels of the reference values sooner when goats were exposed to the uniform than the non-uniform sound. Cardiac activity was not affected by the stimuli. Altogether, the chime of a bell led to higher behavioural arousal than the uniform sinusoidal tone, indicating a potential of the chime to being more aversive to goats than a uniform sound. With repeated exposure to the stimuli, goats habituated to both stimuli, but habituation was faster to the sinusoidal sound than to the chime of a bell. Free-ranging goats in alpine regions usually are equipped with bells 24 h a day during the summer season. Thus, the question arises whether the long-term exposure to the chime of a bell might have negative effects on animal welfare.

    Learn more >>>

  • Does nest size matter to laying hens?

    Authors: Ringgenberg, N., Fröhlich, E., Harlander-Matauschek, A., Würbel, H., Roth, B. (2014)

    Laying hens in loose housing systems have access to group-nests which provide space for several hens at a time to lay their eggs. They are thus rather large and the trend in the industry is to further increase the size of these nests. Though practicality is important for the producer, group-nests should also cater to the egg-laying behaviour of hens to promote good welfare. One of the factors playing a role in the attractiveness of a nest is the amount of enclosure: hens prefer more enclosure when having a choice between different nest types. The aim of this study was to investigate if hens prefer smaller group-nests to lay their eggs given that they may seem more enclosed than larger nests.

    The relative preference of groups of laying hens for two nest sizes – 0.43 m2 vs. 0.86 m2 – was tested in a free-access choice test. The experiment was conducted in two consecutive trials with 100 hens each. They were housed from 18 to 36 weeks of age in five groups of 20 animals and had access to two commercial group-nests differing in internal size only. We counted eggs daily as a measure of nest preference. At 28 and 36 weeks of age, videos were taken of the pens and inside the nests on one day during the first 5 h of lights-on. The nest videos were used to record the number of hens per nest and their behaviour with a 10 min scan sampling interval. The pen videos were observed continuously to count the total number of nest visits per nest and to calculate the duration of nest visits of five focal hens per pen.

    We found a relative preference for the small nest as more eggs, fewer nest visits per egg and longer nest visit durations were recorded for that nest. In addition, more hens – including more sitting hens – were in the small nests during the main egg-laying period, while the number of standing hens did not differ. These observations indicate that even though both nests may have been explored to a similar extent, the hens preferred the small nest for egg-laying.

    Learn more >>>

  • Insect prey characteristics affecting regional variation in chimpanzee tool use

    Authors: Sanz, C., Deblauwe, I., Tagg, N., Morgan, D. (2014)

    It is an ongoing interdisciplinary pursuit to identify the factors shaping the emergence and maintenance of tool technology. Field studies of several primate taxa have shown that tool using behaviors vary within and between populations. While similarity in tools over spatial and temporal scales may be the product of socially learned skills, it may also reflect adoption of convergent strategies that are tailored to specific prey features. Much has been claimed about regional variation in chimpanzee tool use, with little attention to the ecological circumstances that may have shaped such differences. This study examines chimpanzee tool use in termite gathering to evaluate the extent to which the behavior of insect prey may dictate chimpanzee technology. More specifically, we conducted a systematic comparison of chimpanzee tool use and termite prey between the Goualougo Triangle in the Republic of Congo and the La Belgique research site in southeast Cameroon. Apes at both of these sites are known to use tool sets to gather several species of termites. We collected insect specimens and measured the characteristics of their nests. Associated chimpanzee tool assemblages were documented at both sites and video recordings were conducted in the Goualougo Triangle. Although Macrotermitinae assemblages were identical, we found differences in the tools used to gather these termites. Based on measurements of the chimpanzee tools and termite nests at each site, we concluded that some characteristics of chimpanzee tools were directly related to termite nest structure. While there is a certain degree of uniformity within approaches to particular tool tasks across the species range, some aspects of regional variation in hominoid technology are likely adaptations to subtle environmental differences between populations or groups. Such microecological differences between sites do not negate the possibility of cultural transmission, as social learning may be required to transmit specific behaviors among individuals.

    Learn more >>>

  • Investigation of distances covered by fattening pigs measured with VideoMotionTracker

    Authors: Julia Brendle, Steffen Hoy

    The investigation was carried out with altogether 220 pigs kept in groups of 6 or 12. Every pen was equipped with perforated floor. Water and the in-house compound feed with different elements depending on the fattening period were available ad libitum during the whole fattening period. At the beginning of each fattening period all pigs were weighed and the individual rank place was calculated based on 72 h continuous infrared video-recordings. At the beginning, in the middle and at the end of the fattening period the distances covered by focus animals during 24 h were measured using the VideoMotionTracker (VMT) software tool (Mangold). The VideoMotionTracker is a software solution to allow tracking animals on a video recording using the PC mouse or a touch-screen terminal to measure distances that were covered. This measurements on pigs resulted in highly significant differences between the covered distances at the different fattening stages (at the beginning: 582 m; in the middle: 391 m; at the end: 261 m on average). Fattening pigs kept in groups of 12 each covered longer distances during the fattening period compared with pigs kept in groups of 6 (459 m versus 333 m). The differences between the means were highly significant (p < 0.001). On average female pigs covered a longer distance than castrated male pigs (443 m versus 349 m). The factor rank position did not show any significant influence on the covered distance of each focus animal. Pigs with high rank positions on average covered 399 m whereas pigs with low rank positions covered with 393 m a marginally shorter distance. Furthermore the interaction between fattening period and rank position was examined but did not show any significance either. The influence of the factor pen within group size was highly significant (p < 0.001) and the parameters live weight and covered distances were negatively correlated.

    Download
  • Effect of group size, phase of fattening period, gender and rank position on distances covered by fattening pigs

    Authors: Julia Brendle, Steffen Hoy

    Poster Presentation at ISAE 2012, Vienna, Austria

    Download
  • Tool Use in Animals

    Authors: C. Sanz, J. Call, C. Boesch

    Capuchin Monkeys cracking nuts with stones or chimpanzees catching termites with sticks. These are examples of animals that use tools inventively – mostly to tap into food sources. The book, “Tool Use in Animals”, offers the interdisciplinary insight into the topic of tool use in animals, recently published by Cambridge Publishing House.

    The book examines the cognitive abilities and environmental factors that have shaped the tool development and tool use in animals. What makes this book extremely special: The animals were not observed in laboratory studies, but in the wild. Thus, the publication is a fascinating read and is not only aimed at scientific readership.

    “Tool Use in Animals” presents contributions from several leading authors from psychology, biology and anthropology. The editors are Dr. Crickette Sanz, anthropologist at Washington University, Dr. Josep Call, psychologist at Max-Planck-Institute and Professor Christophe Boesch, director of the Max-Planck-Instituts for Evolutionary Anthropology.

    Dr. Crickette Sanz is also a member of the Mangold Scientific Council and engaged in the Goualougo Triangle Ape Project which is dedicated to research and preservation of great apes in the Congo.

    Learn more >>>

  • Contextualised behavioural measurements of personality differences obtained in behavioural tests and social observations in adult capuchin monkeys (Cebus apella)

    Authors: Jana Uher, Elsa Addessi, Elisabetta Visalberghi

    We applied a new framework for behavioural research on personality differences in 26 adult tufted capuchin monkeys. Using the Behavioural Repertoire x Environmental Situations Approach, we generated systematically 20 non-lexical emic personality constructs that have high ecological validity for this species. For construct operationalisation, we obtained 146 contextualised behavioural measures repeatedly in 15 experimental situations and 2 group situations using computerised and video-assisted methods. A complete repetition after a 2–3-week break within a 60-day period yielded significant test–retest reliability from individual-oriented and variable-oriented viewpoints at different levels of aggregation. In accordance with well-established findings on cross-situational consistency, internal consistency was only moderate. This new and important finding highlights fundamental differences between behavioural approaches and judgment-based approaches to personality differences.

    Link to "Journal of Research in Personality" >>>

  • Aping expressions: Chimpanzees produce distinct laugh types when responding to laughter of others

    Authors: M. Davila Ross, B. Allcock, C. Thomas, K.A. Bard

    Humans have the ability to replicate the emotional expressions of others even when they undergo different emotions. Such distinct responses of expressions, especially positive expressions, play a central role in everyday social communication of humans and may give the responding individuals important advantages in cooperation and communication.

    Download
  • Responding to inequities: Gorillas try to maintain their competitive advantage during play fights

    Authors: E.J.C. van Leeuwen, E. Zimmermann, M. Davila Ross

    Human respond to unfair situations in various ways. Experimental research has revealed that non-human species also respond to unequal situations in the form of inequity aversions when they have the disadvantage.

    Download
  • A dual function of echolocation: bats use echolocation calls to identify familiar and unfamiliar individuals

    Authors: Silke L. Voigt-Heucke, Michael Taborsky, Dina K.N. Dechmann

    Bats use echolocation for orientation during foraging and navigation. However, it has been suggested that echolocation calls may also have a communicative function, for instance between roost members. In principle, this seems possible because echolocation calls are species specific and known to differ between the sexes, and between colonies and individuals for some species. We performed playback experiments with lesser bulldog bats, Noctilio albiventris, to which we presented calls of familiar/unfamiliar conspecifics, cohabitant/noncohabitant heterospecifics and ultrasonic white noise as a control. Bats reacted with a complex repertoire of social behaviours and the intensity of their response differed significantly between stimulus categories. Stronger reactions were shown towards echolocation calls of unfamiliar conspecifics than towards heterospecifics and white noise. To our knowledge, this is the first time that bats have been found to react to echolocation calls with a suite of social behaviours. Our results also provide the first experimental evidence for acoustical differentiation by bats between familiar and unfamiliar conspecifics, and of heterospecifics. Analysis of echolocation calls confirmed significant individual differences between echolocation calls. In addition, we found a nonsignificant trend towards group signatures in echolocation calls of N. albiventris. We suggest that echolocation calls used during orientation may also communicate species identity, group affiliation and individual identity. Our study highlights the communicative potential of sonar signals that have previously been categorized as cues in animal social systems.

    Link to "Animal Behaviour" website >>>

  • Genetic Architecture of Tameness in a Rat Model of Animal Domestication

    Authors: Frank W. Albert

    Abstract of the main publication: A common feature of domestic animals is tameness—i.e., they tolerate and are unafraid of human presence and handling. To gain insight into the genetic basis of tameness and aggression, we studied an intercross between two lines of rats (Rattus norvegicus) selected over.60 generations for increased tameness and increased aggression against humans, respectively. We measured 45 traits, including tameness and aggression, anxiety-related traits, organ weights, and levels of serum components in .700 rats from an intercross population. Using 201 genetic markers, we identified two significant quantitative trait loci (QTL) for tameness. These loci overlap with QTL for adrenal gland weight and for anxiety-related traits and are part of a five-locus epistatic network influencing tameness. An additional QTL influences the occurrence of white coat spots, but shows no significant effect on tameness. The loci described here are important starting points for finding the genes that cause tameness in these rats and potentially in domestic animals in general.

    Link to Genetics website >>>

  • Rapid facial mimicry in orangutan play

    Authors: Marina Davila Ross, Susanne Menzler and Elke Zimmermann

    Abstract
    Emotional contagion enables individuals to experience emotions of others. This important empathic phenomenon is closely linked to facial mimicry, where facial displays evoke the same facial expressions in social partners. In humans, facial mimicry can be voluntary or involuntary, whereby its latter mode can be processed as rapid as within or at 1 s. Thus far, studies have not provided evidence of rapid involuntary facial mimicry in animals.

    This study assessed whether rapid involuntary facial mimicry is present in orangutans (Pongo pygmaeus; NZ25) for their open-mouth faces (OMFs) during everyday dyadic play. Results clearly indicated that orangutans rapidly mimicked OMFs of their playmates within or at 1 s. Our study revealed the first evidence on rapid involuntary facial mimicry in non-human mammals. This finding suggests that fundamental building blocks of positive emotional contagion and empathy that link to rapid involuntary facial mimicry in humans have homologues in non-human primates.

    Download
  • Responding to inequities: gorillas try to maintain their competitive advantage during play fights

    Authors: Edwin Van Leeuwen, Elke Zimmermann and Marina Davila Ross

    Abstract: Humans respond to unfair situations in various ways. Experimental research has revealed that non-human species also respond to unequal situations in the formof inequity aversions when they have the disadvantage. The current study focused on play fights in gorillas to explore for the first time, to our knowledge, if/how non-human species respond to inequities in natural social settings. Hitting causes a naturally occurring inequity among individuals and here it was specifically assessed how the hitters and their partners engaged in play chases that followed the hitting. The results of this work showed that the hitters significantly more often moved first to run away immediately after the encounter than their partners. These findings provide evidence that non-human species respond to inequities by trying to maintain their competitive advantages. We conclude that non-human primates, like humans, may show different responses to inequities and that they may modify them depending on if they have the advantage or the disadvantage.

    Download
  • Kin recognition in the grey mouse lemur (Microcebus murinus)

    Authors: Institute of Zoology, University of Veterinary Medicine Hannover / Lab course: Experimental Behavioural Biology

    Abstract
    Kin recognition is a prerequisite for kin selection. Kin selection has been theorized as a driving force behind the evolution of group-living in primates. vocal recognition of kin has been observed in haplorhine primates (Rendall, 2004) and in the diurnal, gregarious strepsirrhine, Lemur catta (Nunn, 2000). Much less research has been done on the vocalizations of the nocturnal, solitarily foraging strepsirrhines. Our study is the first to test for vocal recognition of kin in a nongregarious strepsirrhine. Mouse lemurs are small-boiled, nocturnal, solitarily foraging strepsirrhine primates that have dispersed social networks (Braune et al., 2008). We have testet whether M. murinus females respond differently to and whistles, an alarm call (Braune et al., 2008), and trills, advertisement calls, given by their father and by unrelated males.

    Download
  • Food preference in two mouse lemur species (Microcebus lehilahytsara &amp; Microcebus murinus)

    Authors: Institute of Zoology, University of Veterinary Medicine Hannover / Lab course: Experimental Behavioural Biology

    Abstract
    Two different species of mouse lemurs (Microcebus lehilahytsara and M. murinus) were tested for their food preferences. Four different food items were presented in a two paired choice test to find the most adequate reward for upcoming behavioural tests.

    Download
  • Acoustic cues of caller identity and affect intensity in communication calls of tree shrews (Tupaia belangeri)

    Authors: Institute of Zoology, University of Veterinary Medicine Hannover / Lab course: Experimental Behavioural Biology

    Abstract
    Comparative studies on the vocalisation of humans and animals have shown that structural and temporal variations in communication sounds serve several functions, such as to reliably transmit the affective state and individuality of the sender. These variations within a call type are named acoustic cues and are ghoutght to be important factors in the communication process of social living animals. In the present study, we have examined attention calls of tree shrews (Tupaia belangeri) for acoustic cues conveying the affective state and/or individuality of the sender. Any general physiological activation of the nervous system in a tree shrew leads to defined changes in its behavioural patterns. When aroused, it raises its tail/ruffles its tail hair and sometimes utters attention calls (von Holst, 1977). Tree shrews utter these calls in their natural habitat, when they are confronted with new environmental stimuli (Emmons, 2000).

    Download
  • Personality in the behaviour of great apes - temporal stability, cross-situational consistency

    Authors: Jana Uher, Jens B. Asendorpf and Josep Call

    Abstract
    Using a multidisciplinary approach, the present study complements ethological behaviour measurements with basic theoretical concepts, methods and approaches of the personality psychological trait paradigm. Its adoptability and usefulness for animal studies is tested exemplarily on a sample of 20 zoo-housed great apes (five of each of the following species): bonobos, Pan paniscus; chimpanzees, Pan troglodytes verus; gorillas, Gorilla gorilla gorilla; and orang-utans, Pongo pygmaeus abelii. Data on 76 single trait-relevant behaviours were recorded in a series of 14 laboratory based situations and in two different group situations. Data collection was repeated completely after a break of two weeks within a 50-day period. All behaviour records were sufficiently reliable. Individual- and variable-oriented analyses showed high/substantial temporal stability on different levels of aggregation. Distinctive and stable individual situational and response profiles clarified the importance of situations and of multiple trait-relevant behaviours. The present study calls for a closer collaboration between personality psychologists and behavioural biologists to tap the full potential of animal personality research.

    Download
  • Personality assessment in the Great Apes: Comparing ecologically valid behavior measures, behavior ratings, and adjective ratings

    Authors: Jana Uher and Jens B. Asendorpf

    Abstract
    Three methods of personality assessment (behavior measures, behavior ratings, adjective ratings) were compared in 20 zoo-housed Great Apes: bonobos (Pan paniscus), chimpanzees (Pan troglodytes verus), gorillas (Gorilla gorilla gorilla), and orangutans (Pongo pygmaeus abelii). To test a new bottom-up approach, the studied trait constructs were systematically generated from the species’ behavioral repertoires. The assessments were reliable, temporally stable, and showed substantial cross-method coherence. In most traits, behavior ratings mediated the relations between adjective ratings and behavior measures. Results suggest that high predictability of manifest behavior is best achieved by behavior ratings, not by adjectives. Empirical evidence for trait constructs beyond current personality models points to the necessity of broad and systematic approaches for valid inferences on a species’ personality structure.

    Download
  • Cooperative Activities in Young Children and Chimpanzees

    Authors: Felix Warneken, Frances Chen and Michael Tomasello

    Abstract
    Human children 18 – 24 months of age and 3 young chimpanzees interacted in 4 cooperative activities with a human adult partner. The human children successfully participated in cooperative problem-solving activities and social games, whereas the chimpanzees were uninterested in the social games. As an experimental manipulation, in each task the adult partner stopped participating at a specific point during the activity. All children produced at least one communicative attempt to reengage him, perhaps suggesting that they were trying to reinstate a shared goal. No chimpanzee ever made any communicative attempt to reengage the partner. These results are interpreted as evidence for a uniquely human form of cooperative activity involving shared intentionality that emerges in the second year of life.

    Download
  • Computer Supported Measurement of Distance Moved by Rabbits a day by Mangold Video Motion Tracker

    Authors: Steffen Hoy, Justus Liebig University of Gießen

    Abstract
    Because of several reasons it was necessary to develop and to test a new software solution to analyze the distance moved by farm animals in the field.

    Download