Home [1–10] << 11 12 13 14 15 16 17 18 19 20 >> [21–21]
List View
 | 
Citations
 | 
Details
   web
Records
Author (up) Toro, J.M.; Trobalon, J.B.; Sebastian-Galles, N.
Title The use of prosodic cues in language discrimination tasks by rats Type Journal Article
Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 6 Issue 2 Pages 131-136
Keywords *Animal Communication; Animals; *Discrimination Learning; Female; *Language; Male; Periodicity; Rats; Rats, Long-Evans; Speech Perception
Abstract Recent research with cotton-top tamarin monkeys has revealed language discrimination abilities similar to those found in human infants, demonstrating that these perceptual abilities are not unique to humans but are also present in non-human primates. Specifically, tamarins could discriminate forward but not backward sentences of Dutch from Japanese, using both natural and synthesized utterances. The present study was designed as a conceptual replication of the work on tamarins. Results show that rats trained in a discrimination learning task readily discriminate forward, but not backward sentences of Dutch from Japanese; the results are particularly robust for synthetic utterances, a pattern that shows greater parallels with newborns than with tamarins. Our results extend the claims made in the research with tamarins that the capacity to discriminate languages from different rhythmic classes depends on general perceptual abilities that evolved at least as far back as the rodents.
Address SPPB, Departament de Psicologia Basica, Universitat de Barcelona, Passeig de la Vall d'Hebron, 171, 08035 Barcelona, Spain. jmtoro@psi.ub.es
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1435-9448 ISBN Medium
Area Expedition Conference
Notes PMID:12728358 Approved no
Call Number Equine Behaviour @ team @ Serial 2571
Permanent link to this record
 
 
Author (up) Touma, C.; Sachser, N.; Mostl, E.; Palme, R.
Title Effects of sex and time of day on metabolism and excretion of corticosterone in urine and feces of mice Type Journal Article
Year 2003 Publication General and Comparative Endocrinology Abbreviated Journal Gen Comp Endocrinol
Volume 130 Issue 3 Pages 267-278
Keywords Animals; Chromatography, High Pressure Liquid; Circadian Rhythm/*physiology; Corticosterone/*metabolism/urine; Feces/*chemistry; Female; Immunoenzyme Techniques; Kinetics; Male; Mice; Mice, Inbred C57BL; Reference Values; Sex Factors; Stress/metabolism; Time Factors; Tritium
Abstract Non-invasive techniques to monitor stress hormones in small animals like mice offer several advantages and are highly demanded in laboratory as well as in field research. Since knowledge about the species-specific metabolism and excretion of glucocorticoids is essential to develop such a technique, we conducted radiometabolism studies in mice (Mus musculus f. domesticus, strain C57BL/6J). Each mouse was injected intraperitoneally with 740 kBq of 3H-labelled corticosterone and all voided urine and fecal samples were collected for five days. In a first experiment 16 animals (eight of each sex) received the injection at 9 a.m., while eight mice (four of each sex) were injected at 9 p.m. in a second experiment. In both experiments radioactive metabolites were recovered predominantly in the feces, although males excreted significantly higher proportions via the feces (about 73%) than females (about 53%). Peak radioactivity in the urine was detected within about 2h after injection, while in the feces peak concentrations were observed later (depending on the time of injection: about 10h postinjection in experiment 1 and about 4h postinjection in experiment 2, thus proving an effect of the time of day). The number and relative abundance of fecal [3H]corticosterone metabolites was determined by high performance liquid chromatography (HPLC). The HPLC separations revealed that corticosterone was extensively metabolized mainly to more polar substances. Regarding the types of metabolites formed, significant differences were found between males and females, but not between the experiments. Additionally, the immunoreactivity of these metabolites was assessed by screening the HPLC fractions with four enzyme immunoassays (EIA). However, only a newly established EIA for 5alpha-pregnane-3beta,11beta,21-triol-20-one (measuring corticosterone metabolites with a 5alpha-3beta,11beta-diol structure) detected several peaks of radioactive metabolites with high intensity in both sexes, while the other EIAs showed only minor immunoreactivity. Thus, our study for the first time provides substantial information about metabolism and excretion of corticosterone in urine and feces of mice and is the first demonstrating a significant impact of the animals' sex and the time of day. Based on these data it should be possible to monitor adrenocortical activity non-invasively in this species by measuring fecal corticosterone metabolites with the newly developed EIA. Since mice are extensively used in research world-wide, this could open new perspectives in various fields from ecology to behavioral endocrinology.
Address Department of Behavioral Biology, Institute of Neuro and Behavioral Biology, University of Muenster, Badestrasse 9, D-48149 Muenster, Germany. touma@uni-muenster.de
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0016-6480 ISBN Medium
Area Expedition Conference
Notes PMID:12606269 Approved no
Call Number Equine Behaviour @ team @ Serial 4086
Permanent link to this record
 
 
Author (up) Uller, C.; Jaeger, R.; Guidry, G.; Martin, C.
Title Salamanders ( Plethodon cinereus) go for more: rudiments of number in an amphibian Type Journal Article
Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 6 Issue 2 Pages 105-112
Keywords Animals; *Cognition; Discrimination Learning; Female; Male; Mathematics; *Urodela
Abstract Techniques traditionally used in developmental research with infants have been widely used with nonhuman primates in the investigation of comparative cognitive abilities. Recently, researchers have shown that human infants and monkeys select the larger of two numerosities in a spontaneous forced-choice discrimination task. Here we adopt the same method to assess in a series of experiments spontaneous choice of the larger of two numerosities in a species of amphibian, red-backed salamanders ( Plethodon cinereus). The findings indicate that salamanders “go for more,” just like human babies and monkeys. This rudimentary capacity is a type of numerical discrimination that is spontaneously present in this amphibian.
Address Institute of Cognitive Science, University of Louisiana at Lafayette, Lafayette, LA 70504-3772, USA. uller@louisiana.edu
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1435-9448 ISBN Medium
Area Expedition Conference
Notes PMID:12709845 Approved no
Call Number Equine Behaviour @ team @ Serial 2575
Permanent link to this record
 
 
Author (up) Valero, N.
Title West Nile virus: a new challenge? Type Journal Article
Year 2003 Publication Investigacion Clinica Abbreviated Journal Invest Clin
Volume 44 Issue 3 Pages 175-177
Keywords Animal Migration; Animals; Bird Diseases/virology; Birds; Caribbean Region; Central America; Culex/virology; Horse Diseases/virology; Horses; Humans; Insect Vectors/virology; North America/epidemiology; South America; West Nile Fever/*epidemiology/transmission/veterinary; West Nile virus/*physiology
Abstract West Nile Virus (WNV), a member of the family Flaviviridae, was first isolated in 1937. Since the original isolation of the WNV outbreaks have occurred with increase in frequency of cases in humans and horses, apparent increase in severe human disease and high avian death rates. In 1999, 2000 and 2002 outbreaks of the WNV encephalitis were reported in horses, birds and humans from New York and Canada. Ornithophilic mosquitoes are the principal vectors of the WNV and birds of several species chiefly migrants appear to be the major introductory or amplifying host. The pattern of outbreaks in the old and new world suggests that viremic migratory birds may also contribute to movement of the virus. If so, Central America, Caribbean Islands and countries of South America including Venezuela, are in potential risk for suffering a severe outbreak for WNV, since several species of birds have populations that pass trough New York and cross the western north Atlantic or Caribbean Sea. It is important the knowledge of the ecology of WNV as well of the efficacy of control efforts in order to minimize the public health impact in these countries, where all population is susceptible to this infection.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Spanish Summary Language Original Title Virus del Nilo Occidental: Un nuevo reto?
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0535-5133 ISBN Medium
Area Expedition Conference
Notes PMID:14552056 Approved no
Call Number Equine Behaviour @ team @ Serial 2640
Permanent link to this record
 
 
Author (up) van der Willigen, R.F.; Frost, B.J.; Wagner, H.
Title How owls structure visual information Type Journal Article
Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 6 Issue 1 Pages 39-55
Keywords Animals; *Cognition; Depth Perception; Discrimination Learning; Female; Male; *Strigiformes; *Visual Perception
Abstract Recent studies on perceptual organization in humans claim that the ability to represent a visual scene as a set of coherent surfaces is of central importance for visual cognition. We examined whether this surface representation hypothesis generalizes to a non-mammalian species, the barn owl ( Tyto alba). Discrimination transfer combined with random-dot stimuli provided the appropriate means for a series of two behavioural experiments with the specific aims of (1) obtaining psychophysical measurements of figure-ground segmentation in the owl, and (2) determining the nature of the information involved. In experiment 1, two owls were trained to indicate the presence or absence of a central planar surface (figure) among a larger region of random dots (ground) based on differences in texture. Without additional training, the owls could make the same discrimination when figure and ground had reversed luminance, or were camouflaged by the use of uniformly textured random-dot stereograms. In the latter case, the figure stands out in depth from the ground when positional differences of the figure in two retinal images are combined (binocular disparity). In experiment 2, two new owls were trained to distinguish three-dimensional objects from holes using random-dot kinematograms. These birds could make the same discrimination when information on surface segmentation was unexpectedly switched from relative motion to half-occlusion. In the latter case, stereograms were used that provide the impression of stratified surfaces to humans by giving unpairable image features to the eyes. The ability to use image features such as texture, binocular disparity, relative motion, and half-occlusion interchangeably to determine figure-ground relationships suggests that in owls, as in humans, the structuring of the visual scene critically depends on how indirect image information (depth order, occlusion contours) is allocated between different surfaces.
Address Institut fur Biologie II, RWTH Aachen, Kopernikusstrasse 16, 52074, Aachen, Germany. willigen@bio2.rwth-aachen.de
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1435-9448 ISBN Medium
Area Expedition Conference
Notes PMID:12658534 Approved no
Call Number Equine Behaviour @ team @ Serial 2582
Permanent link to this record
 
 
Author (up) Van Doorn G.S.; Hengeveld G.M.; Weissing F.J.
Title The Evolution of Social Dominance I: Two-player Models Type Journal Article
Year 2003 Publication Behavior Abbreviated Journal Behavior
Volume 140 Issue 10 Pages 1305-1332
Keywords
Abstract A difference in dominance rank is an often-used cue to resolve conflicts between two animals without escalated fights. At the group level, adherence to a dominance convention efficiently reduces the costs associated with conflicts, but from an individual's point of view, it is difficult to explain why a low ranking individual should accept its subordinate status. This is especially true if, as suggested by several authors, dominance not necessarily reflects differences in fighting ability but rather results from arbitrary historical asymmetries. According to this idea, rank differentiation emerges from behavioural strategies, referred to as winner and loser effects, in which winners of previous conflicts are more likely to win the current conflict, whereas the losers of previous conflicts are less likely to do so. In order to investigate whether dominance, based on such winner and loser effects, can be evolutionarily stable, we analyse a game theoretical model. The model focuses on an extreme case in which there are no differences in fighting ability between individuals at all. The only asymmetries that may arise between individuals are generated by the outcome of previous conflicts. By means of numerical analysis, we find alternative evolutionarily stable strategies, which all utilize these asymmetries for conventional conflict resolution. One class of these strategies is based on winner and loser effects, thus generating evolutionarily stable dominance relations even in the absence of differences in resource holding potential.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5105
Permanent link to this record
 
 
Author (up) Van Doorn G.S.; Hengeveld G.M.; Weissing F.J.
Title The Evolution of Social Dominance II: Multi-Player Models Type Journal Article
Year 2003 Publication Behavior Abbreviated Journal Behavior
Volume 140 Issue 10 Pages 1333-1358
Keywords
Abstract The social hierarchies observed in natural systems often show a high degree of transitivity. Transitive hierarchies do not only require rank differentiation within pairs of individuals but also a higher level ordering of relations within the group. Several authors have suggested that the formation of linear hierarchies at the group level is an emergent property of individual behavioural rules, referred to as winner and loser effects. Winner and loser effects occur if winners of previous conflicts are more likely to escalate the current conflict, whereas the losers of previous conflicts are less likely to do so. According to this idea, an individual's position in a hierarchy may not necessarily reflect its fighting ability, but may rather result from arbitrary historical asymmetries, in particular the history of victories and defeats. However, if this is the case, it is difficult to explain from an evolutionary perspective why a low ranking individual should accept its subordinate status. Here we present a game theoretical model to investigate whether winner and loser effects giving rise to transitive hierarchies can evolve and under which conditions they are evolutionarily stable. The main version of the model focuses on an extreme case in which there are no intrinsic differences in fighting ability between individuals. The only asymmetries that may arise between individuals are generated by the outcome of previous conflicts. We show that, at evolutionary equilibrium, these asymmetries can be utilized for conventional conflict resolution. Several evolutionarily stable strategies are based on winner and loser effects and these strategies give rise to transitive hierarchies.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5106
Permanent link to this record
 
 
Author (up) van Duijn, M. A.J.
Title Software for Social Network Analysis Type Manuscript
Year 2003 Publication Abbreviated Journal
Volume Issue Pages
Keywords
Abstract This chapter gives a state-of-the art overview of available (free and commercial)

software for social network analysis as of fall 2003. It reviews and compares

six programs, illustrating their functionality with example data. Data manipulation

options and available support are also discussed. Furthermore, seventeen

other, of which nine special-purpose, software packages and ve software routine

packages for general statistical software are reviewed brie

y. The chapter

concludes with some recommendations.
Address
Corporate Author Thesis
Publisher Heymans Institute/DPMG Place of Publication University of Groningen Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5205
Permanent link to this record
 
 
Author (up) Vieuille, C.; Berger, F.; Le Pape, G.; Bellanger, D.
Title Sow behaviour involved in the crushing of piglets in outdoor farrowing huts--a brief report Type Journal Article
Year 2003 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.
Volume 80 Issue 2 Pages 109-115
Keywords Pig-maternal behaviour; Crushing; Free-ranging; Welfare
Abstract This study focuses on maternal activities involved in the trapping of piglets by the sow's body in outdoor farrowing systems and examine the mother-piglet context leading either to the death of piglets or to their survival. The behaviour of six Large-WhitexLandrace sows and their litters was continuously video recorded at their first and second parity, during the 40 h following parturition. Crushing mainly occurred at evening and night, during the first 12 h of farrowing and involved changes between lying, sitting and standing positions, as well as between udder and side lying. No piglet died from savaging. Nevertheless, aggressive behaviours of sows were observed, particularly in their first maternal experience. The immediate context of trapping was related to the labour of the sow and to the feeding and resting of piglets. The immediate crushing context was related to active avoidance of restless piglets while lying down, as well as sitting and standing behaviours. These results are discussed in terms of differential reactions of the sow to suckling attempts of piglets.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2235
Permanent link to this record
 
 
Author (up) Visser, E.K.; Van Reenen, C.G.; Engel, B.; Schilder, M.B.H.; Barneveld, A.; Blokhuis, H.J.
Title The association between performance in show-jumping and personality traits earlier in life Type Journal Article
Year 2003 Publication Applied Animal Behaviour Science Abbreviated Journal Appl. Anim. Behav. Sci.
Volume 82 Issue 4 Pages 279-295
Keywords Personality; Performance; Horses; Prediction; Individual differences; Behavioural tests
Abstract For a horse to succeed in a show-jumping career, the individual has to possess both excellent physical abilities as well as a suitable personality to perform under challenging conditions. Forty-one Dutch Warmblood horses were used to develop personality tests and correlations between test variables and early training performances in jumping were studied. In behavioural tests, during the first 2 years of the horses' lives, personality aspects like emotionality, reactivity to human and learning abilities were quantified. At the age of 3, horses were broken and received early training in show-jumping. The inter-relationship between several performance variables measured during this early training phase were studied using principal component analysis (PCA). Variables measured in the different personality tests (novel-object test, handling test, avoidance-learning test and a reward-learning test) showed no correlations, suggesting that these tests all triggered different aspects of a horse's personality. This study indicates that it is possible to predict a substantial part of the show-jumping performance of an individual horse later in life by personality traits earlier in life.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number refbase @ user @ Serial 326
Permanent link to this record