Home [1–10] << 11 12 13 14 >>
List View
 | 
Citations
 | 
Details
   web
Records
Author Tommasi, L.; Vallortigara, G.
Title Searching for the center: spatial cognition in the domestic chick (Gallus gallus) Type Journal Article
Year 2000 Publication Journal of Experimental Psychology. Animal Behavior Processes Abbreviated Journal (up) J Exp Psychol Anim Behav Process
Volume 26 Issue 4 Pages 477-486
Keywords Animals; Behavior, Animal/physiology; Chickens; Cognition/*physiology; Learning/physiology; Male; Space Perception/*physiology; Spatial Behavior/*physiology
Abstract Chicks learned to find food hidden under sawdust by ground-scratching in the central position of the floor of a closed arena. When tested inan arena of identical shape but a larger area, chicks searched at 2 different locations, one corresponding to the correct distance (i.e., center) in the smaller (training) arena and the other to the actual center of the test arena. When tested in an arena of the same shape but a smaller area, chicks searched in the center of it. These results suggest that chicks are able to encode information on the absolute and relative distance of the food from the walls of the arena. After training in the presence of a landmark located at the center of the arena, animals searched at the center even after the removal of the landmark. Marked changes in the height of the walls of the arena produced some displacement in searching behavior, suggesting that chicks used the angular size of the walls to estimate distances.
Address Department of General Psychology, University of Padua, Italy
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 0097-7403 ISBN Medium
Area Expedition Conference
Notes PMID:11056887 Approved no
Call Number Equine Behaviour @ team @ Serial 2774
Permanent link to this record
 
 
Author Brannon, E.M.; Terrace, H.S.
Title Representation of the numerosities 1-9 by rhesus macaques (Macaca mulatta) Type Journal Article
Year 2000 Publication Journal of Experimental Psychology. Animal Behavior Processes Abbreviated Journal (up) J Exp Psychol Anim Behav Process
Volume 26 Issue 1 Pages 31-49
Keywords Animals; *Cognition; Macaca mulatta/*psychology; *Mathematics; Perception; Reaction Time
Abstract Three rhesus monkeys (Macaca mulatta) were trained to respond to exemplars of 1, 2, 3, and 4 in an ascending, descending, or a nonmonotonic numerical order (1-->2-->3-->4, 4-->3-->2--1, 3-->1-->4-->2). The monkeys were then tested on their ability to order pairs of the novel numerosities 5-9. In Experiment 1, all 3 monkeys ordered novel exemplars of the numerosities 1-4 in ascending or descending order. The attempt to train a nonmonotonic order (3-->1-->4-->2) failed. In Experiment 2A, the 2 monkeys who learned the ascending numerical rule ordered pairs of the novel numerosities 5-9 on unreinforced trials. The monkey who learned the descending numerical rule failed to extrapolate the descending rule to new numerosities. In Experiment 2B all 3 monkeys ordered novel exemplars of pairs of the numerosities 5-9. Accuracy and latency of responding revealed distance and magnitude effects analogous to previous findings with human participants (R. S. Moyer & T. K. Landaeur, 1967). Collectively these studies show that monkeys represent the numerosities 1-9 on at least an ordinal scale.
Address Department of Psychology, Columbia University, New York, New York 10027, USA. liz@psych.columbia.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 0097-7403 ISBN Medium
Area Expedition Conference
Notes PMID:10650542 Approved no
Call Number Equine Behaviour @ team @ Serial 2775
Permanent link to this record
 
 
Author Zentall, T.R.; Riley, D.A.
Title Selective attention in animal discrimination learning Type Journal Article
Year 2000 Publication The Journal of general psychology Abbreviated Journal (up) J Gen Psychol
Volume 127 Issue 1 Pages 45-66
Keywords Animals; Attention/*physiology; Behavior, Animal/physiology; Conditioning (Psychology)/physiology; Cues; Discrimination Learning/*physiology; Generalization, Response; Rats
Abstract The traditional approach to the study of selective attention in animal discrimination learning has been to ask if animals are capable of the central selective processing of stimuli, such that certain aspects of the discriminative stimuli are partially or wholly ignored while their relationships to each other, or other relevant stimuli, are processed. A notable characteristic of this research has been that procedures involve the acquisition of discriminations, and the issue of concern is whether learning is selectively determined by the stimulus dimension defined by the discriminative stimuli. Although there is support for this kind of selective attention, in many cases, simpler nonattentional accounts are sufficient to explain the results. An alternative approach involves procedures more similar to those used in human information-processing research. When selective attention is studied in humans, it generally involves the steady state performance of tasks for which there is limited time allowed for stimulus input and a relatively large amount of relevant information to be processed; thus, attention must be selective or divided. When this approach is applied to animals and alternative accounts have been ruled out, stronger evidence for selective or divided attention in animals has been found. Similar processes are thought to be involved when animals search more natural environments for targets. Finally, an attempt is made to distinguish these top-down attentional processes from more automatic preattentional processes that have been studied in humans and other animals.
Address Department of Psychology, University of Kentucky, Lexington 40506, USA. Zentall@pop.uky.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 0022-1309 ISBN Medium
Area Expedition Conference
Notes PMID:10695951 Approved no
Call Number refbase @ user @ Serial 250
Permanent link to this record
 
 
Author Hagen, S.J.; Eaton, W.A.
Title Two-state expansion and collapse of a polypeptide Type Journal Article
Year 2000 Publication Journal of Molecular Biology Abbreviated Journal (up) J Mol Biol
Volume 301 Issue 4 Pages 1019-1027
Keywords Animals; Computer Simulation; Cytochrome c Group/*chemistry/*metabolism; Horses; Kinetics; Lasers; Models, Chemical; Peptides/*chemistry/*metabolism; Protein Conformation; Protein Denaturation; *Protein Folding; Spectrometry, Fluorescence; Temperature; Thermodynamics
Abstract The initial phase of folding for many proteins is presumed to be the collapse of the polypeptide chain from expanded to compact, but still denatured, conformations. Theory and simulations suggest that this collapse may be a two-state transition, characterized by barrier-crossing kinetics, while the collapse of homopolymers is continuous and multi-phasic. We have used a laser temperature-jump with fluorescence spectroscopy to measure the complete time-course of the collapse of denatured cytochrome c with nanosecond time resolution. We find the process to be exponential in time and thermally activated, with an apparent activation energy approximately 9 k(B)T (after correction for solvent viscosity). These results indicate that polypeptide collapse is kinetically a two-state transition. Because of the observed free energy barrier, the time scale of polypeptide collapse is dramatically slower than is predicted by Langevin models for homopolymer collapse.
Address Laboratory of Chemical Physics, NIDDK, National Institutes of Health, Building 5, Bethesda, MD, 20892-0520, USA
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 0022-2836 ISBN Medium
Area Expedition Conference
Notes PMID:10966803 Approved no
Call Number Equine Behaviour @ team @ Serial 3790
Permanent link to this record
 
 
Author Pierce, M.M.; Nall, B.T.
Title Coupled kinetic traps in cytochrome c folding: His-heme misligation and proline isomerization Type Journal Article
Year 2000 Publication Journal of Molecular Biology Abbreviated Journal (up) J Mol Biol
Volume 298 Issue 5 Pages 955-969
Keywords Amino Acid Sequence; Amino Acid Substitution/genetics; Binding Sites; Cytochrome c Group/*chemistry/genetics/*metabolism; *Cytochromes c; Enzyme Stability/drug effects; Fluorescence; Guanidine/pharmacology; Heme/*metabolism; Histidine/genetics/*metabolism; Hydrogen-Ion Concentration; Isomerism; Kinetics; Models, Molecular; Molecular Sequence Data; Mutation/genetics; Proline/*chemistry/metabolism; Protein Conformation/drug effects; Protein Denaturation/drug effects; *Protein Folding; Protein Renaturation; Saccharomyces cerevisiae/enzymology/genetics; Sequence Alignment; Thermodynamics
Abstract The effect of His-heme misligation on folding has been investigated for a triple mutant of yeast iso-2 cytochrome c (N26H,H33N,H39K iso-2). The variant contains a single misligating His residue at position 26, a location at which His residues are found in several cytochrome c homologues, including horse, tuna, and yeast iso-1. The amplitude for fast phase folding exhibits a strong initial pH dependence. For GdnHCl unfolded protein at an initial pH<5, the observed refolding at final pH 6 is dominated by a fast phase (tau(2f)=20 ms, alpha(2f)=90 %) that represents folding in the absence of misligation. For unfolded protein at initial pH 6, folding at final pH 6 occurs in a fast phase of reduced amplitude (alpha(2f) approximately 20 %) but the same rate (tau(2f)=20 ms), and in two slower phases (tau(m)=6-8 seconds, alpha(m) approximately 45 %; and tau(1b)=16-20 seconds, alpha(1b) approximately 35 %). Double jump experiments show that the initial pH dependence of the folding amplitudes results from a slow pH-dependent equilibrium between fast and slow folding species present in the unfolded protein. The slow equilibrium arises from coupling of the His protonation equilibrium to His-heme misligation and proline isomerization. Specifically, Pro25 is predominantly in trans in the unligated low-pH unfolded protein, but is constrained in a non-native cis isomerization state by His26-heme misligation near neutral pH. Refolding from the misligated unfolded form proceeds slowly due to the large energetic barrier required for proline isomerization and displacement of the misligated His26-heme ligand.
Address Center for Biomolecular Structure, Department of Biochemistry, University of Texas Health Science Center, 7703 Floyd Curl Drive, San Antonio, TX 78229-3900, USA
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 0022-2836 ISBN Medium
Area Expedition Conference
Notes PMID:10801361 Approved no
Call Number refbase @ user @ Serial 3853
Permanent link to this record
 
 
Author Goodloe, R.B
Title Population characteristics of feral horses on Cumberland Island, Georgia and their management implications Type Journal Article
Year 2000 Publication Journal of Wildlife Management Abbreviated Journal (up) J Wildl Manag
Volume 64 Issue 1 Pages 114-121
Keywords
Abstract
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 937-2817 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 2296
Permanent link to this record
 
 
Author Lanier, J.L.; Grandin, T.; Green, R.D.; Avery, D.; McGee, K.
Title The relationship between reaction to sudden, intermittent movements and sounds and temperament Type Journal Article
Year 2000 Publication Journal of Animal Science Abbreviated Journal (up) J. Anim Sci.
Volume 78 Issue 6 Pages 1467-1474
Keywords
Abstract N1 -
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 2945
Permanent link to this record
 
 
Author Olesen, I.; Groen, A.F.; Gjerde, B.
Title Definition of animal breeding goals for sustainable production systems Type Journal Article
Year 2000 Publication Journal of Animal Science Abbreviated Journal (up) J. Anim Sci.
Volume 78 Issue 3 Pages 570-582
Keywords
Abstract N1 -
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 2934
Permanent link to this record
 
 
Author Marc, M.; Parvizi, N.; Ellendorff, F.; Kallweit, E.; Elsaesser, F.
Title Plasma cortisol and ACTH concentrations in the warmblood horse in response to a standardized treadmill exercise test as physiological markers for evaluation of training status Type Journal Article
Year 2000 Publication Journal of Animal Science Abbreviated Journal (up) J. Anim Sci.
Volume 78 Issue 7 Pages 1936-1946
Keywords Adrenocorticotropic Hormone/*blood/diagnostic use; Animals; Catheterization/veterinary; Exercise Test; Horses/*blood; Hydrocortisone/*blood; Male; *Physical Conditioning, Animal
Abstract Reliable physiological markers for performance evaluation in sport horses are missing. To determine the diagnostic value of plasma ACTH and cortisol measurements in the warmblood horse, 10 initially 3-yr-old geldings of the Hannovarian breed were either exposed to a training schedule or served as controls. During experimental Phase 1, horses were group-housed, and half of the horses were trained for 20 wk on a high-speed treadmill. During Phase 2, groups were switched and one group was trained for 10 wk as during Phase 1, whereas the control group was confined to boxes. During Phase 3 horses were initially schooled for riding. Thereafter, all horses were regularly schooled for dressage and jumping, and half of the horses received an additional endurance training for 24 wk. During all phases horses were exposed at regular intervals to various standardized treadmill exercise tests. During and after the tests frequent blood samples were taken from an indwelling jugular catheter for determination of ACTH and cortisol. Treadmill exercise increased both hormones. Maximum ACTH concentrations were recorded at the end of exercise, and maximum cortisol levels were recorded 20 to 30 min later. Except for one test there were no differences in ACTH levels between trained horses and controls. There was no significant effect of training on the cortisol response (net increase) to treadmill exercise in any of the tests during Phase 1. During Phase 2 higher cortisol responses were recorded in controls than in trained horses (P < .05) after 10 wk of training (controls confined to boxes). During Phase 3 plasma cortisol responses were also higher in controls than in trained horses (P < .05 after 6, 18, and 24, P < or = .07 after 12 wk of training) when the inclination of the treadmill was 5%, but not at 3%. There was no overlap in net cortisol responses at 30 min between trained and untrained horses. An ACTH application after 24 wk of training resulted in higher cortisol responses in controls than in trained horses (P < or = .05), without any overlap between the groups at 30 min after ACTH. Plasma cortisol responses to either treadmill exercise or ACTH injection may be a reliable physiological marker for performance evaluation. Prerequisites are sufficient differences in training status and sufficient intensity of exercise test conditions.
Address Institute of Animal Science and Animal Behaviour, Federal Agricultural Research Center (FAL) Mariensee, Neustadt, 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 0021-8812 ISBN Medium
Area Expedition Conference
Notes PMID:10907837 Approved no
Call Number Equine Behaviour @ team @ Serial 3732
Permanent link to this record
 
 
Author Linklater, W.L.; Henderson, K.M.; Cameron, E.Z.; Stafford, K.J.; Minot, E.O.
Title The robustness of faecal steroid determination for pregnancy testing Kaimanawa feral mares under field conditions Type Journal Article
Year 2000 Publication New Zealand veterinary journal Abbreviated Journal (up) N Z Vet J
Volume 48 Issue 4 Pages 93-98
Keywords
Abstract AIMS: To investigate the utility of faecal oestrone sulphate (OS) concentrations for detecting pregnancy in mares during behavioural studies of feral horses, in which the collection and preservation of samples is not immediate. METHODS: Oestrone sulphate concentrations were measured in fresh dung samples collected from 153 free-roaming Kaimanawa mares throughout the year. In addition, multiple samples were taken from the same pile to investigate the reliability of diagnosis from a single sample, as well as the influence of time until preservation on OS concentrations. Samples were also taken before and after a 10mm simulated rainfall event to test for dilution of OS concentrations by rain. Oestrone sulphate concentrations in all samples were measured using an enzyme immunoassay. RESULTS: From approximately 150 to 250 days of gestation, OS concentrations were consistently >80 ng/g in mares which subsequently foaled. Mares which did not foal and had low faecal OS concentrations in multiple samples throughout the year had faecal OS concentrations of 31+/-13 ng/g (mean+/-s.d.) with an upper 95% confidence limit of 57 ng/g. Mares sampled from 1 week before to 1 month after behavioural oestrus, and that did not foal in the previous and subsequent seasons, had OS concentrations of 37+/-32 ng/g (mean+/-s.d.) with an upper 95% confidence limit of 100 ng/g. The standard error of oestrone sulphate concentrations in multiple samples from the same dung pile ranged from 1 to 37% of the mean. This large within-pile variation, however, did not result in incorrect diagnoses from single samples unless mares were within 18 days of parturition. Keeping samples at ambient temperatures for up to 16 hours did not affect OS concentrations. Simulated rainfall caused a 17% mean reduction in OS concentrations, but did not change pregnancy diagnoses. CONCLUSIONS: Faecal OS concentrations >100 ng/g were indicative of pregnancy in Kaimanawa mares. For mares more than 150 days post-mating, OS concentrations <57 ng/g were indicative of non-pregnancy, while concentrations between 57 and 100 ng/g provided an inconclusive diagnosis. A single sample from each dung pile collected within 16 hours of defecation was sufficient to accurately diagnose pregnancy in mares 150-250 days post conception. CLINICAL RELEVANCE: Measurement of OS concentrations in dung samples was a reliable and robust indicator of pregnancy status in feral mares 150-250 days post mating. This corresponds approximately to the period from May to August, given the seasonal breeding pattern in this population. This method of determining pregnancy status is suitable for field use in behavioural and demographic studies of wild horse populations.
Address Ecology Group, Institute of Natural Resources, Massey University, Private Bag 11-222, Palmerston North, New Zealand. wlinklater@hotmail.com
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 0048-0169 ISBN Medium
Area Expedition Conference
Notes PMID:16032132 Approved no
Call Number refbase @ user @ Serial 411
Permanent link to this record