|   | 
Details
   web
Records
Author Imura, T.; Tomonaga, M.
Title Perception of depth from shading in infant chimpanzees ( Pan troglodytes) Type Journal Article
Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 6 Issue 4 Pages 253-258
Keywords Age Factors; Animals; Contrast Sensitivity/*physiology; Depth Perception/*physiology; Discrimination Learning/*physiology; Female; Male; Pan troglodytes/growth & development/*physiology/*psychology; Pattern Recognition, Visual/physiology
Abstract We investigated the ability to perceive depth from shading, one of the pictorial depth cues, in three chimpanzee infants aged 4-10 months old, using a preferential reaching task commonly used to study pictorial depth perception in human infants. The chimpanzee infants reached significantly more to three-dimensional toys than to pictures thereof and more to the three-dimensional convex than to the concave. Furthermore, two of the three infants reached significantly more to the photographic convex than to the photographic concave. These infants also looked longer at the photographic convex than the concave. Our results suggest that chimpanzees perceive, at least as early as the latter half of the first year of life, pictorial depth defined by shading information. Photographic convexes contain richer information about pictorial depth (e.g., attached shadow, cast shadow, highlighted area, and global difference in brightness) than simple computer-graphic graded patterns. These cues together might facilitate the infants' perception of depth from shading.
Address (up) Graduate School of Humanities, Kwansei Gakuin University, Uegahara, Nishinomiya, Hyogo 662-8501, Japan
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:14610661 Approved no
Call Number Equine Behaviour @ team @ Serial 2550
Permanent link to this record
 

 
Author Kuroshima, H.; Fujita, K.; Adachi, I.; Iwata, K.; Fuyuki, A.
Title A Capuchin monkey (Cebus apella) recognizes when people do and do not know the location of food Type Journal Article
Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 6 Issue 4 Pages 283-291
Keywords Adaptation, Psychological; Animals; Cebus/*psychology; *Communication; Concept Formation; *Cues; *Discrimination Learning; Feeding Behavior/*psychology; Female; Intention; Male; Social Identification; Transfer (Psychology)
Abstract In a previous study, Kuroshima and colleagues demonstrated that capuchin monkeys (Cebus apella) learned to discriminate between a “knower” who inspected a box for food, and a “guesser” who did not. The aim of the present study was to specify whether the subjects learned a simple conditional discrimination or a causal relationship that seeing leads to knowing. In experiment 1, we introduced five types of novel containers to two subjects. Each container was of different shape and color. The subjects gradually learned to reach toward the container the knower suggested. In experiment 2, we diversified the behavior of the knower and the guesser. In experiment 3, in order to eliminate the possibility of discrimination based on differences in the magnitude and the complexity of two trainers, we equated their behaviors. One subject adapted to the novel behaviors of the knower and the guesser, successfully discriminating the two trainers. Thus this monkey clearly learned to use the inspecting action of the knower and the non-inspecting action of the guesser as a discriminative cue to recognize the baited container. This result suggests that one capuchin monkey learned to recognize the relationship between seeing and knowing.
Address (up) Graduate School of Letters, Department of Psychology, Kyoto University, Yoshida-honmachi, Sakyo, 606-8501 Kyoto, Japan. kuroshi@psy.bun.kyoto-u.ac.jp
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:12905080 Approved no
Call Number Equine Behaviour @ team @ Serial 2558
Permanent link to this record
 

 
Author Westerduin, F.E.; Lankveld, D.P.K.; van der Velden, M.A.; Back, W.; Sloet van Oldruitenborgh-Oosterbaan, M.M.
Title [Splenectomy in a dressage pony: end of sports career?] Type Journal Article
Year 2003 Publication Tijdschrift Voor Diergeneeskunde Abbreviated Journal Tijdschr Diergeneeskd
Volume 128 Issue 13 Pages 406-411
Keywords Animals; Biopsy/veterinary; Colic/surgery/veterinary; Horse Diseases/pathology/*surgery/ultrasonography; Horses; Laparotomy/veterinary; Male; Splenectomy/*veterinary; Splenomegaly/surgery/ultrasonography/*veterinary; *Sports
Abstract A 14-year-old Arabian cross-bred gelding was referred to the University Clinic because of mild, recurrent signs of colic for 5 days. The pony showed icteric mucous membranes, haemolytic blood, and dark coloured urine. Internal examination did not give a clear diagnosis. Unidentified intra-abdominal strands were found and haemorrhagic abdominocentesis led to the decision to perform an exploratory laparatomy. An extremely enlarged spleen was the sole finding. A splenal biopsy sample was taken and surgery was completed. The pony remained colicky, so the spleen was examined by ultrasonography. After this examination, the tentative diagnosis 'tumour of the spleen' was made and splenectomy was performed. Pathological examination of the spleen revealed splenomegaly caused by infarctions of unknown origin. Eight weeks after surgery, the pony started again in dressage competition. Six months after splenectomy, the pony won the provincial dressage competition.
Address (up) Hoofdafdeling Gezondheidszorg Paard, Faculteit der Diergeneeskunde, Universiteit Utrecht, Yalelaan 12-16, 3584 CM Utrecht. fenna-lambert@planet.nl
Corporate Author Thesis
Publisher Place of Publication Editor
Language Dutch Summary Language Original Title Splenectomie bij een dressuurpony: einde sportcarriere?
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0040-7453 ISBN Medium
Area Expedition Conference
Notes PMID:12870176 Approved no
Call Number Equine Behaviour @ team @ Serial 3722
Permanent link to this record
 

 
Author 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 (up) 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 Vollmerhaus, B.; Roos, H.; Gerhards, H.; Knospe, C.
Title [Phylogeny, form and function of canine teeth in the horse] Type Journal Article
Year 2003 Publication Anatomia, histologia, embryologia Abbreviated Journal Anat Histol Embryol
Volume 32 Issue 4 Pages 212-217
Keywords Animals; Cuspid/*anatomy & histology/radiography; Evolution; Horses/*anatomy & histology; Male; Phylogeny; *Social Dominance
Abstract The canine teeth of the horse developed phylogenically from the simple, pointed, short-rooted tooth form of the leaf eating, in pairs living, Eocene horse Hyracotherium and served up to the Oligocene as a means of defense (self preservation). In the Miocene the living conditions of the Merychippus changed and they took to eating grass and adopted as a new behavior the life in a herd. The canine teeth possibly played an important role in fights for social ranking; they changed from a crown form to knife-like shape. In the Pliohippus the canine tooth usually remained in male horses and since the Pliocene, it contributed to the fights between stallions, to ensure that the offspring only came from the strongest animals (preservation of the species). Form and construction of the canine tooth are described and discussed in detail under the above mentioned phylogenic and ethologic aspects.
Address (up) Institut fur Tieranatomie und Chirurgische Tierklinik der Universitat Munchen, Veterinarstrasse 13, D 80539 Munchen, Deutschland. c-neumueller@anat.vetmed.uni-muenchen.de
Corporate Author Thesis
Publisher Place of Publication Editor
Language German Summary Language Original Title [Zur Phylogenie, Form und Funktion der Dentes canini des Pferdes]
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0340-2096 ISBN Medium
Area Expedition Conference
Notes PMID:12919071 Approved no
Call Number refbase @ user @ Serial 672
Permanent link to this record
 

 
Author Wallner, B.; Brem, G.; Muller, M.; Achmann, R.
Title Fixed nucleotide differences on the Y chromosome indicate clear divergence between Equus przewalskii and Equus caballus Type Journal Article
Year 2003 Publication Animal Genetics Abbreviated Journal Anim Genet
Volume 34 Issue 6 Pages 453-456
Keywords Animals; Base Sequence; DNA, Mitochondrial/genetics; Genetic Variation/*genetics; Horses/classification/*genetics; Male; Molecular Sequence Data; Phylogeny; Probability; Species Specificity; Y Chromosome/*genetics
Abstract The phylogenetic relationship between Equus przewalskii and E. caballus is often a matter of debate. Although these taxa have different chromosome numbers, they do not form monophyletic clades in a phylogenetic tree based on mtDNA sequences. Here we report sequence variation from five newly identified Y chromosome regions of the horse. Two fixed nucleotide differences on the Y chromosome clearly display Przewalski's horse and domestic horse as sister taxa. At both positions the Przewalski's horse haplotype shows the ancestral state, in common with the members of the zebra/ass lineage. We discuss the factors that may have led to the differences in mtDNA and Y-chromosomal observations.
Address (up) Institut fur Tierzucht und Genetik, Veterinarmedizinische Universitat Wien, Veterinarplatz, Wien, Austria. wallner@i122server.vu-wien.ac.at
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 0268-9146 ISBN Medium
Area Expedition Conference
Notes PMID:14687077 Approved no
Call Number Equine Behaviour @ team @ Serial 5038
Permanent link to this record
 

 
Author Passler, S.; Pfeffer, M.
Title Detection of antibodies to alphaviruses and discrimination between antibodies to eastern and western equine encephalitis viruses in rabbit sera using a recombinant antigen and virus-specific monoclonal antibodies Type Journal Article
Year 2003 Publication Journal of Veterinary Medicine. B, Infectious Diseases and Veterinary Public Health Abbreviated Journal J Vet Med B Infect Dis Vet Public Health
Volume 50 Issue 6 Pages 265-269
Keywords Animals; Antibodies, Monoclonal/*immunology; Antibodies, Viral/*analysis/blood; DNA Primers; Encephalitis Virus, Eastern Equine/genetics/*immunology; Encephalitis Virus, Western Equine/genetics/*immunology; Encephalomyelitis, Equine/*diagnosis/*virology; Epitopes; Fluorescent Antibody Technique/*veterinary; Horses; Rabbits; Recombination, Genetic; Reverse Transcriptase Polymerase Chain Reaction/veterinary
Abstract Three arthropod-borne alphaviruses, western equine encephalitis viruses (WEEV), eastern equine encephalitis viruses (EEEV) and Venezuelan equine encephalitis viruses are the aetiological agents of a sometimes severe encephalomyelitis in equines and humans in the New World. With regard to the different ecology and epidemiology of these viruses, a method applied in serological screening should be able to distinguish between them as well as other related members of the genus Alphavirus in the American continent. However, this has been hampered in the past by (a) the close antigenic relationship between alphaviruses in traditional serological assays, especially in the routinely used haemagglutination-inhibition, and (b) the need of biosafety level 3 facilities to grow the viral antigens. An epitope blocking assay using an EEEV glycoprotein E1-expressing recombinant Sindbis virus and virus-specific monoclonal antibodies (mAbs) binding to the E1 of EEEV (strain NJ/60) and the E1 of Sindbis virus was established using automated flow cytometry. The test was evaluated using sera of infected and vaccinated rabbits. A cut-off value of 30% inhibition for antigenic complex-specific seroconversion was found to be sufficient for the detection of the respective infection. By using three different mAbs in parallel, we were able to detect alphavirus genus-, EEEV- and WEEV-complex-specific serum antibodies. As this test is based on the inhibition of binding of virus-specific mAbs, sera of every origin other than mouse can be tested. Thus, this assay may prove useful in the serological screening of a variety of animal species during an outbreak investigation.
Address (up) Institute for Medical Microbiology, Infectious and Epidemic Diseases, Veterinary Faculty, Ludwig-Maximilians-University, Munich, Germany
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 0931-1793 ISBN Medium
Area Expedition Conference
Notes PMID:14628996 Approved no
Call Number Equine Behaviour @ team @ Serial 2639
Permanent link to this record
 

 
Author Bachmann, I.; Audige, L.; Stauffacher, M.
Title Risk factors associated with behavioural disorders of crib-biting, weaving and box-walking in Swiss horses Type Journal Article
Year 2003 Publication Equine Veterinary Journal Abbreviated Journal Equine Vet J
Volume 35 Issue 2 Pages 158-163
Keywords Animal Husbandry/*methods; Animals; *Behavior, Animal; Confounding Factors (Epidemiology); Data Collection; Female; Horse Diseases/epidemiology/*etiology/prevention & control; Horses; *Housing, Animal; Male; Mental Disorders/epidemiology/etiology/prevention & control/*veterinary; Prevalence; Regression Analysis; Risk Factors; *Stereotyped Behavior; Switzerland/epidemiology
Abstract REASONS FOR PERFORMING STUDY: Studies on the prevalence of behavioural disorders in horses and on associated risk factors have revealed inconsistent results. There are many studies on the neuropharmacological, surgical or mechanical therapy of stereotypies, but little is known about their causation. OBJECTIVES: To explore risk factors associated with the occurrence of behavioural disorders in horses. METHODS: A sample of horse owners, selected randomly and representative for Switzerland, was contacted in a postal survey. Answers were provided for 622 stables (response rate 35.2%). Individual data of 2,341 horses were examined with path analysis (multivariable linear and logistic regression), and adjustment made for possible confounding effects due to age and breed. RESULTS: Out of 60 possible risk factors, 11 were associated with the outcome at the univariable level (null-hypothesis path model) and 3 factors remained after the backward logistic regression procedure. Mature Warmbloods and Thoroughbreds, assessed by the owners to be reactive, fed 4 times a day and without daily pasture, had increased odds of displaying crib-biting, weaving and box-walking. Furthermore, indirect associations of 5 factors with the outcome were identified. CONCLUSIONS: The final logistic regression model of risk factors leads to the hypotheses that causal prevention of stereotypic behaviours should be based upon housing and management conditions which allow tactile contact with other horses (e.g. mutual grooming), daily free movement (paddock or pasture), as well as the provision of high amounts of roughage but of little or no concentrates. POTENTIAL CLINICAL RELEVANCE: It is one of the aims of population medicine to prevent the development of behavioural disorders. Further research is needed to test the concluding hypotheses in experimental studies or to verify them in the context of similar observational studies.
Address (up) Institute of Animal Sciences, Swiss Federal Institute of Technology (ETH), LFW B55. 1, CH-8092 Zurich, Switzerland
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 0425-1644 ISBN Medium
Area Expedition Conference
Notes PMID:12638792 Approved no
Call Number Serial 1907
Permanent link to this record
 

 
Author 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 (up) 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 Katz, M.; Lachlan, R.F.
Title Social learning of food types in zebra finches (Taenopygia guttata) is directed by demonstrator sex and feeding activity Type Journal Article
Year 2003 Publication Animal Cognition Abbreviated Journal Anim. Cogn.
Volume 6 Issue 1 Pages 11-16
Keywords Animals; Color; Diet; *Feeding Behavior; Female; *Learning; Male; Sex Factors; *Social Behavior; *Songbirds
Abstract In this study we examined how social learning of feeding preferences by zebra finches was affected by the identity of different demonstrators. We presented adult zebra finches with two demonstrators, one male and one female, that exhibited different food choices, and we recorded their subsequent preference when given a choice between the two food types. Previously it was found that young zebra finches' patterns of social learning are affected by the sex of the individual demonstrating a feeding behaviour. This result could be explained by the lack of exposure these animals had to the opposite sex, or by their mating status. Therefore, we investigated the social learning preferences of adult mated zebra finches. We found the same pattern of directed social learning of a different type of feeding behaviour (food colour): female zebra finches preferred the colour of food eaten by male demonstrators, whereas male zebra finches showed little evidence of any preference for the colour of food eaten by female demonstrators. Furthermore, we found that female observers' preferences were biased by demonstrators' relative feeding activity: the female demonstrator was only ever preferred if it ate less than its male counterpart.
Address (up) Institute of Evolutionary and Ecological Science, University of Leiden, Kaiserstraat 63, 2311GP, Leiden, The Netherlands
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:12658531 Approved no
Call Number Equine Behaviour @ team @ Serial 2585
Permanent link to this record